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Space Junks

The mystery of Venus' ashen light

 

May is the best time to try and spot one of the most enduring unsolved mysteries in our Solar System. Ashen Light is a faint glow allegedly seen on the unlit portion of Venus, during its crescent phase, similar to the earth shine often observed on the Moon, though not as bright. It is more commonly observed while Venus occupies the evening sky, as now, than when it is in the morning sky. But no one really knows for sure what causes it.

So what’s the history of our knowledge about this enigmatic glow?

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The whole story on dark matter

After all, we spend our entire lives on one rocky world, that's just one of many planets orbiting our Sun, which is just one star among hundreds of billions in our Milky Way galaxy, which is just one galaxy among hundreds of billions that make up our observable Universe.

Yes, we've learned an awful lot about what's out there and our place in it. As best as we can tell, we've learned what the fundamental laws are that govern everything in it, too!

Read full article >

Lunar Satellite Reveals Apollo 16 Remains

 


NASA’s Lunar Reconnaissance Orbiter (LRO) made a low pass over the Apollo 16 site last fall, capturing images of the leftovers from John Young and Charlie Duke’s 1972 exploration of the Descartes Highlands. The video above takes us on a tour of the Apollo 16 site from lunar orbit, and includes audio from the original communications and some very nice comparative photos and video clips showing the same features from ground level.

The goal of Apollo 16 was to explore for the first time a lunar highlands location, and collect samples of what were initially thought to be volcanic rocks. The rocks were believed to be of a different material than what was collected during previous missions.

As it turned out, the rocks collected by Duke and Young weren’t volcanic in origin at all; they ended up being breccias — cemented-together chunks ejected from ancient cratering events hundreds of miles away.

Apollo 16 also set up various experiment packages to study lunar geology, magnetism and the solar wind. The Lunar Roving Vehicle (LRV) allowed Young and Duke to travel across a much wider area than they would have otherwise been able to on foot. It was the second mission to use an LRV, and the rover — as well as its tracks — are still there today, looking exactly as they did when they were left 40 years ago.

LROC image of the Apollo 16 site showing the Orion LM. (NASA/GSFC/Arizona State University)

The Apollo 16 ascent stage lifted off from the lunar surface on the evening of April 23, 1972 and docked with the Command Module containing Ken Mattingly. The following day the astronauts began their trip back to Earth, completing the 250,000-mile traverse three days later on April 27.

The Moon would be visited again in December of that same year during Apollo 17, the last mission of the program and the last time that humans would walk on the surface of another world. Now, 40 years later, satellites orbiting the Moon take pictures of what was left behind by these historic events. Perhaps someday soon the sites will be visited from ground level… maybe even by a new generation of astronauts.

Panorama of the Descartes Highlands site made from 3 Hasselblad film image scans combined together. (NASA/JSC/J. Major)

 

 

 

 

New Gigantic Tornado Spotted on Mars

 

 

A Martian dust devil roughly 12 miles (20 kilometers) high was captured winding its way along the Amazonis Planitia region of Northern Mars on March 14, 2012 by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. Despite its height, the plume is little more than three-quarters of a football field wide (70 yards, or 70 meters). Image credit: NASA/JPL-Caltech/UA 

Last month, we were excited to share an image of a twister on Mars that lofted a twisting column of dust more than 800 meters (about a half a mile) high. We now know that’s nothin’ — just peanuts, chump change, hardly worth noticing. The Mars Reconnaissance Orbiter has now spotted a gigantic Martian dust devil roughly 20 kilometers (12 miles) high, churning through the Amazonis Planitia region of northern Mars. The HiRISE camera (High Resolution Imaging Science Experiment) captured the event on March 14, 2012. Scientists say that despite its height, the plume is just 70 meters (70 yards) wide.

Yikes! After seeing trucks thrown about by the tornadoes in Dallas yesterday, it makes you wonder how the MER rovers and even the Curiosity rover would fare in an encounter with a 20-km high twister.

The image was taken during late northern spring, two weeks short of the northern summer solstice, a time when the ground in the northern mid-latitudes is being heated most strongly by the sun.

Dust devils are spinning columns of air, made visible by the dust they pull off the ground. Unlike a tornado, a dust devil typically forms on a clear day when the ground is heated by the sun, warming the air just above the ground. As heated air near the surface rises quickly through a small pocket of cooler air above it, the air may begin to rotate, if conditions are just right.

Obviously, conditions were more than just right to create such a whopper.

 

 

             

  

 

Shaking Up Theories Of Earth’s Formation

 

Earth may not have formed quite like once thought (Image: NASA/Suomi NPP)

Researchers from The Australian National University are suggesting that Earth didn’t form as previously thought, shaking up some long-standing hypotheses of our planet’s origins right down to the core — literally.

Ian Campbell and Hugh O’Neill, both professors at ANU’s Research School for Earth Sciences, have challenged the concept that Earth formed from the same material as the Sun — and thus has a “chondritic” composition — an idea that has been assumed accurate by planetary scientists for quite some time.

 

Chondrite meteorites are composed of spherical chondrules, which formed in the solar nebula before the asteroids. (NASA)

Chondrites are meteorites that were formed from the solar nebula that surrounded the Sun over 4.6 billion years ago. They are valuable to scientists because of their direct relationship with the early Solar System and the primordial material they contain.

“For decades it has been assumed that the Earth had the same composition as the Sun, as long the most volatile elements like hydrogen are excluded,” O’Neill said. “This theory is based on the idea that everything in the solar system in general has the same composition. Since the Sun comprises 99 per cent of the solar system, this composition is essentially that of the Sun.”

Instead, they propose that our planet was formed through the collision of larger planet-sized bodies, bodies that had already grown massive enough themselves to develop an outer shell.

This scenario is supported by over 20 years of research by Campbell on columns of hot rock that rise from Earth’s core, called mantle plumes. Campbell discovered no evidence for “hidden reservoirs” of heat-producing elements such as uranium and thorium that had been assumed to exist, had Earth actually formed from chondritic material.

“Mantle plumes simply don’t release enough heat for these reservoirs to exist. As a consequence the Earth simply does not have the same composition as chondrites or the Sun,” Campbell said.

The outer shell of early Earth, containing heat-producing elements obtained from the impacting smaller planets, would have been eroded away by all the collisions.

“This produced an Earth that has fewer heat producing elements than chondritic meteorites, which explains why the Earth doesn’t have the same chemical composition,” O’Neill said.

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Pioneer 10: The mission that opened the final frontier

 

Until 40 years ago, the farthest any man-made object had ventured into space was Mars and many scientists believed that this might be as far as we could ever go.

Beyond Mars, there lay an impenetrable 180million km-wide barrier made up of colossal rocks, barreling through space and tens of thousands of kilometres per hour – the asteroid belt – and any craft that ventured into it would be doomed. At least that was the theory.

Then, forty years ago this month, Nasa put the theory to the test. Launched on March 2, 1972, Pioneer 10 left Earth on a mission to study Jupiter. To reach it, it would have to traverse the asteroid belt.

Graphic: The Pioneer 10 spacecraft

Graphic: Everything you need to know about Pioneer 10 (well, maybe not everything...). 

A few months later Pioneer 10 entered the belt but, instead of being smashed to a metallic pulp, it sailed through without a hitch. It turned out that, far from being a densely-packed, highway of rocky death, the asteroid belt was mostly empty space. The solar system was now ours to explore.

Pioneer went on to become the first man-made object to study Jupiter and the first to cross the orbits of Saturn, Neptune, Uranus and Pluto. Long after its intended 21-month lifespan had been exceeded, Pioneer 10 kept on trucking until 2003, when, at the outer limits of our solar system and 12.2 billion km from home, it sent its last transmission.

Pioneer 10 (and its sister craft Pioneer 11 – launched in 1973 to visit Saturn) is one of the great space adventures and it paved the way for many more.

Graphic: The journey of Pioneer 10

Graphic: Pioneer's epic journey and scale of the solar system-type thing. 

So where is Pioneer 10 now?

The craft is now coasting at 13 km/s (28,000mph) toward the red star Aldebaran, which lies 71 light years away and shines 155 times more brightly than our own Sun.

It is expected to arrive in about 2 million years...

... in science fiction land, Pioneer 10's fate was little different.

In Star Trek V: the Final Frontier. A trigger-happy Klingon named Captain Klaa blasted Pioneer 10 to smithereens for target practice.

 

Dawn Sees New Surface Features on Giant Asteroid

 

In this image from NASA's Dawn spacecraft, bright material extends out from the crater Canuleia on Vesta. The bright material appears to have been thrown out of the crater during the impact that created it.
This image, made from data obtained by NASA's Dawn spacecraft, shows a perspective view of a layered young crater in the Rheasilvia basin at Vesta.This image, made from data obtained by NASA's Dawn spacecraft, shows a perspective view of a layered young crater in the Rheasilvia basin at Vesta. The interplay of bright and dark material at the rim of Marcia crater on Vesta is visible in this image mosaic taken by NASA's Dawn spacecraft.The interplay of bright and dark material at the rim of Marcia crater on Vesta is visible in this image mosaic taken by NASA's Dawn spacecraft.
This image from NASA's Dawn spacecraft shows a young crater on Vesta that is 9 miles (15 kilometers) in diameter.This image from NASA's Dawn spacecraft shows a young crater on Vesta that is 9 miles (15 kilometers) in diameter.

 

PASADENA, Calif. – NASA's Dawn spacecraft has revealed unexpected details on the surface of the giant asteroid Vesta. New images and data highlight the diversity of Vesta's surface and reveal unusual geologic features, some of which were never previously seen on asteroids.

These results were discussed today at the Lunar and Planetary Science Conference at The Woodlands, Texas.

Vesta is one of the brightest objects in the solar system and the only asteroid in the so-called main belt between Mars and Jupiter visible to the naked eye from Earth. Dawn has found that some areas on Vesta can be nearly twice as bright as others, revealing clues about the asteroid's history.

"Our analysis finds this bright material originates from Vesta and has undergone little change since the formation of Vesta over 4 billion years ago," said Jian-Yang Li, a Dawn participating scientist at the University of Maryland, College Park. "We're eager to learn more about what minerals make up this material and how the present Vesta surface came to be."

Bright areas appear everywhere on Vesta but are most predominant in and around craters. The areas vary from several hundred feet to around 10 miles (16 kilometers) across. Rocks crashing into the surface of Vesta seem to have exposed and spread this bright material. This impact process may have mixed the bright material with darker surface material.

While scientists had seen some brightness variations in previous images of Vesta from NASA's Hubble Space Telescope, Dawn scientists also did not expect such a wide variety of distinct dark deposits across its surface. The dark materials on Vesta can appear dark gray, brown and red. They sometimes appear as small, well-defined deposits around impact craters. They also can appear as larger regional deposits, like those surrounding the impact craters scientists have nicknamed the "snowman."

"One of the surprises was the dark material is not randomly distributed," said David Williams, a Dawn participating scientist at Arizona State University, Tempe. "This suggests underlying geology determines where it occurs."

The dark materials seem to be related to impacts and their aftermath. Scientists theorize carbon-rich asteroids could have hit Vesta at speeds low enough to produce some of the smaller deposits without blasting away the surface.

Higher-speed asteroids also could have hit Vesta's surface and melted the volcanic basaltic crust, darkening existing surface material. That melted conglomeration appears in the walls and floors of impact craters, on hills and ridges, and underneath brighter, more recent material called ejecta, which is material thrown out from a space rock impact.

Vesta's dark materials suggest the giant asteroid may preserve ancient materials from the asteroid belt and beyond, possibly from the birth of the solar system.

"Some of these past collisions were so intense they melted the surface," said Brett Denevi, a Dawn participating scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "Dawn's ability to image the melt marks a unique find. Melting events like these were suspected, but never before seen on an asteroid."

Dawn launched in September 2007. It will reach its second destination, Ceres, in February 2015.

"Dawn's ambitious exploration of Vesta has been going beautifully," said Marc Rayman, Dawn chief engineer at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "As we continue to gather a bounty of data, it is thrilling to reveal fascinating alien landscapes."

 

Dawn's mission is managed by JPL for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. in Dulles, Va., designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. JPL is managed for NASA by the California Institute of Technology in Pasadena.

 

Why Are Lunar Shadows So Dark?

 

A lunar boulder peeks out into the sunlight. (NASA/GSFC/Arizona State University)

A lunar boulder catches the last edge of the setting sunlight in this image from the Lunar Reconnaissance Orbiter Camera. The boulders litter the floor of an unnamed 3.5 km wide (2.17 mile wide) crater located within the much larger crater Lobachevskiy. The smaller crater’s rim casts its shadow along the left side of the image, and raises the question: why are shadows on the Moon so dark?

On Earth, air scatters light and allows objects not in direct sunlight to be still well-lit. This is an effect called Rayleigh scattering, named for the British Nobel-winning physicist Lord Rayleigh (John William Strutt.) Rayleigh scattering is the reason why the sky is blue, and (for the most part) why you can still read a magazine perfectly well under an umbrella at the beach.

On the Moon there is no air, no Rayleigh scattering. So shadows are very dark and, where sunlight hits, very bright. Shadowed areas are dramatically murky, like in the LROC image above, yet there’s still some light bouncing around in there — this is due to reflected light from the lunar surface itself.

Buzz was well-lit by reflected light, even in Eagle's shadow. (NASA/Apollo Image Archive)

Lunar regolith is composed of fine, angular particles of very reflective dust. It tends to reflect light directly back at the source, and will illuminate objects within shadows as well — as seen in Apollo mission photographs. Astronauts within the shadow of the landing modules were still visible, and their suits were well illuminated by reflected light from the lunar surface. Some people have used this as “proof” that the landings were actually filmed on a sound stage under artificial lights, but in reality it’s all due to reflected light.

Here’s a great run-though of the lunar landing photos and how lighting on the Moon works.

So even though air isn’t scattering the sunlight on the Moon, there’s still enough reflection to sneak light into the shadows… but not much. It gets dark — and quickly cold — in there!

And if you’re one of those who likes to get a better look into the shadows, here’s the same image above with the dark areas brightened enough to see details:

Shadow world revealed! (NASA/GSFC/Arizona State University/J. Major)

Some interesting boulder trails in there!

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Saturn’s “Wispy” Moon Has An Oxygen Atmosphere

There’s oxygen around Dione, one of Saturn’s 62 known moons, a research team led by scientists at New Mexico’s Los Alamos National Laboratory announced on Friday. The presence of molecular oxygen around Dione creates an intriguing possibility for organic compounds — the building blocks of life — to exist on other outer planet moons.   

Dione (pronounced DEE-oh-nee) is a 698-mile (1,123-km) -wide moon orbiting Saturn at about the same distance that our Moon orbits Earth. Heavily cratered and crisscrossed by long, bright scarps, Dione is made mostly of water ice and  rock. It makes a complete orbit of Saturn every 2.7 days.

Data acquired during a flyby of the moon by the Cassini spacecraft in 2010 have been found by the Los Alamos researchers to confirm the presence of molecular oxygen high in Dione’s extremely thin atmosphere — so thin, in fact, that scientists prefer the term exosphere.

While you couldn’t take a deep breath on Dione, the presence of O2 indicates a dynamic process in action.

“The concentration of oxygen in Dione’s atmosphere is roughly similar to what you would find in Earth’s atmosphere at an altitude of about 300 miles,” said Robert Tokar, researcher at Los Alamos National Laboratory and lead author of the paper published in Geophysical Research Letters.  “It’s not enough to sustain life, but—together with similar observations of other moons around Saturn and Jupiter—these are definitive examples of a process by which a lot of oxygen can be produced in icy celestial bodies that are bombarded by charged particles or photons from the Sun or whatever light source happens to be nearby.”

On Dione the energy source is Saturn’s powerful magnetic field. As the moon orbits the giant planet, charged ions in Saturn’s magnetosphere slam into the surface of Dione, stripping oxygen from the ice on it surface and crust. This molecular oxygen (O2) flows into Dione’s exosphere, where it is then steadily blown into space by — once again — Saturn’s magnetic field.

Cassini’s instruments detected the oxygen in Dione’s wake during an April 2010 flyby.

Molecular oxygen, if present on other moons as well (say, Europa or Enceladus) could potentially bond with carbon in subsurface water to form the building blocks of life. Since there’s lots of water ice on moons in the outer solar system, as well as some very powerful magnetic fields emanating from planets like Jupiter and Saturn, there’s no reason to think there isn’t more oxygen to be found… in our solar system or elsewhere.

 

 

 

 

Dark Matter Core Defies Explanation

                                                                   Dark Matter Core Defies Explanation in Hubble Image

March 2, 2012: Astronomers observed what appeared to be a clump of dark matter left behind during a bizarre wreck between massive clusters of galaxies. The dark matter collected into a "dark core" containing far fewer galaxies than would be expected if the dark matter and galaxies hung together. Most of the galaxies apparently have sailed far away from the collision. This result could present a challenge to basic theories of dark matter, which predict that galaxies should be anchored to the invisible substance, even during the shock of a collision.                                                                                                                                                                                                The initial observations, made in 2007, were so unusual that astronomers shrugged them off as unreal, due to poor data. However, new results obtained in 2008 from NASA's Hubble Space Telescope confirm that dark matter and galaxies parted ways in the gigantic merging galaxy cluster called Abell 520, located 2.4 billion light-years away. Now, astronomers are left with the challenge of trying to explain dark matter's seemingly oddball behavior in this cluster.

 

 

 

 

 

Our Early Universe: Inflation, or Something Totally Wacky?

 

A schematic look at the universe - where it came from and where it is now. Credit: NASA.

Astronomers generally accept the theory that our universe looks the way it does because of cosmic inflation — rapid expansion in the moments after its birth. This explains the expanse and apparent flat shape of the universe observed through instruments like NASA’s Wilkinson Microwave Anisotropy Probe. But inflation isn’t the only model that explains the early universe. There are others, and they get wacky. 

Three physicists from the University at Buffalo — Ghazal Geshnizjani, Will Kinney and Azadeh Moradinezhad Dizgah — set out to investigate other cosmic models. Their study titled “General Conditions for Scale-Invariant Perturbations in an Expanding Universe” appeared in November in the online Journal of Cosmology and Astroparticle Physics and contained some interesting results.

This picture of the infant universe from NASA's Wilkinson Microwave Anisotropy Probe (WMAP) reveals 13 billion+ year old temperature fluctuations that correspond to the seeds that grew to become the galaxies. Credit: NASA Goddard Space Flight Center.

They stuck with the basics — that the theory of gravity is correct and that the early universe did rapidly expand. With these two constraints, the team found that only three models explain the early universe and the distribution of matter we observe today. But these models require                                                                                                                                                                              very strange physics.

According to their calculations, the early universe required an accelerated cosmic expansion (inflation), a speed of sound faster than the speed of light, or extremely high cosmic energy to end up with our current universe. The third model actually demands such high energy that scientists would need to invoke a theory of quantum gravity like string theory to explain the extra dimensions of space-time that would pop up. . 

   

The takeaway message? Inflation turns out to be the only way to explain the universe within the context of standard physics, said Kinney. He allows that someone might come up with exotic physics to explain or create other models, like a speed of sound faster than that of light, but suspects people are more comfortable working with models that fit within commonly accepted laws of particle physics.

The difficulty of explaining other models, said Kinney, “puts the idea of inflation on a much stronger footing, because the available alternatives have problems, or weirdnesses, with them.”

Cosmic inflation incorporates quantum field theory to explain the distribution of matter in the universe. Under normal circumstances, particles of matter and antimatter can pop into existence suddenly before colliding and annihilating each other instantly. These pairs flew apart so rapidly after the universe’s birth that they didn’t have a chance to recombine. The same theory applies to gravitons and antigravitons, which form gravity waves.

These particles of matter are the basis of all structure in the universe today. Tiny fluctuations cause matter to collapse and form stars, planes, and galaxies.

But the hunt for other viable models continues. Kinney for one isn’t finished exploring other theories, including those that rely on superluminal sound speeds. There may yet be some major changes to our understanding of the cosmos.

 

 

 

 

 

SOLID Clues for Finding Life on Mars

 

Microbes have been found flourishing beneath the surface of the Atacama Desert. (Parro et al./CAB/SINC)

Researchers from the Center of Astrobiology (CAB) in Spain and the Catholic University of the North in Chile have found an “oasis” of microorganisms living two meters beneath the arid soil of the Atacama, proving that even on the driest place on Earth, life finds a way.

Chile’s Atacama Desert receives on average less than .01 cm (.004 inches) of rain per year. In some locations rain has not fallen for over 400 years. But even in this harsh environment there is moisture… just enough, at least, for rock salts and other compounds that can absorb any traces of water to support microbial life beneath the surface.

Using a device called SOLID (Signs Of LIfe Detection) developed by CAB, the researchers were able to identify the presence of microorganisms living on thin films of water within the salty subsurface soil.

Even the substrate itself is able to absorb moisture from the air, concentrating it into films only a few microns thick around the salt crystals. This gives the microorganisms everything they need to survive and flourish — two to three meters underground.

SOLID's array of life-detector modules. (CAB)

At that depth, there is no sunlight and no oxygen, but there is life.

And even when researchers dug to a depth of five meters (a little over 16 feet) and took samples back to a lab, they were able to not only locate microorganisms but also revive them with the addition of a little water.

Of course, the implications for finding life — or at least the remains of its past existence — on Mars is evident. Mars has been shown to have saline deposits in many regions, and the salt is what helps water remain liquid, longer.

“The high concentration of salt has a double effect: it absorbs water between the crystals and lowers the freezing point, so that they can have thin films of water (in brine) at temperatures several degrees below zero, up to minus 20 C,” said Victor Parro, researcher from the Center of Astrobiology (INTA-CSIC, Spain) and coordinator of the study. This is within the temperature range of many regions of Mars, and also anything located several meters below the surface would be well protected from UV radiation from the Sun.

“If there are similar microbes on Mars or remains in similar conditions to the ones we have found in Atacama, we could detect them with instruments like SOLID,” Parro said.

The development of a new version of the SOLID instrument is currently underway for ESA’s ExoMars program.

 

What might be found just a few feet under the surface of Mars? (NASA/JPL-Caltech)

 

 

 

 

 

Thar she blows!

 

Nasa goes all Ahab and plans to harpoon a comet

Man has always hunted. Even before prehistory ditched the ‘pre’ part of its name and became just history, man has used harpoons to make the hunt easier – especially when there was water involved.

Before history even considered dropping its prefix, hunters used long sharp pointy things to spear fish. But sometimes the fish slipped off the end. Then some bright spark had the idea of putting a barbed end on the sharp pointy thing and the harpoon was born.

For centuries, the harpoon was the weapon of choice for hunting at sea but, lately, it has fallen out of vogue.

Nasa are planning to rehabilitate the harpoon but, instead of hunting whales at sea, they will be hunting comets in space.

Astronomers are fascinated by comets. These frozen chunks of dust and ice were formed when the solar system was still a baby (that’s well before history, prehistory or any other sort of history) and they have remained unchanged ever since. As such, they are like frozen time capsules, crammed full of information about the origin of the solar system.

Astronomers would love to get their hands on a sample of comet and unlock its secrets.

To make their wish a reality, Nasa will be equipping a comet-hunting spacecraft called OSIRIS-REx with a harpoon and, to complete the historical synergy, they will fire it from a crossbow.

A comet can move through space quite quickly (about 240,000kph) so landing a craft on its surface is a bit tricky. The craft, which is planned to launch in 2016, will use a two-metre crossbow to fire a high-speed harpoon with a special hollowed-out tip into the comet’s surface. The harpoon will grab a sample from inside the comet and then the sample will be winched back to OSIRIS-REx and returned to Earth.

But comet hunting isn’t as straightforward as you’d think – you can’t just grab a harpoon and go at it.

So, ‘Call me Ishmael’ and check out our comet-hunting guide.

The hunter’s guide to comets: Expert tips to help you bag your prize

So you think you know a comet when you see one?

Well, think again. They only adopt their full comety plumage when they pass close to the Sun. Without the Sun’s warmth, the water and gases that form the comet’s tell-tale tail stay frozen solid – locked away in the comet’s nucleus (during long hunts, entertain yourself by repeating “tell-tale tail” as fast as you can).

Because comets have such huge orbits, they spend most of their time a long way from the Sun’s warmth. This means that comets can spend 99 per cent of their lives looking an awful lot likeasteroids, so if you’re not careful a comet could pass right by you and you’d never know.

When you do get your quarry in your sights, don’t be fooled by its size –it’s not as big as it looks. Most of what you can see is just a cloud of gas.

The comet’s nucleus is just a tiny speck somewhere in the middle. The cloud is created by gas that vents out of the comet when it is warmed by the Sun. So, although your target might appear to be hundreds of thousands of kilometres across, if you don’t aim for the comet’s tiny heart, your harpoon will just sail harmlessly through.

If you think you can wait for a comet to pass by before you shoot it, think again. Comets can come from deep space, which gives them plenty of time to pick up speed. Some could be moving as fast as70km/sec (relative to Earth), whereas the fastest bullet can only reach about 1km/sec. You will either need to get in front of the comet to shoot it as it streaks towards you (not recommended), or you’ll need to match the comet’s speed yourself.

Intuition tells us that the tail of gas and dust trailing from a comet should be an indication of the comet’s direction of travel. After all, if you throw a ball with a streamer attached to it, the streamer will drag behind the ball. But if you try to anticipate a comet’s movements by looking at its tail, your ambush could be doomed to fail.

A comet’s tail is actually being blown away from the comet by the solar wind. So, all the tail can tell you for certain is where the Sun is (and if you can’t see the Sun already, you shouldn’t be hunting). To make matters worse, comet orbits are hard to predict. All that gas venting from a comet’s surface can act like the manoeuvring thrusters on a space craft – suddenly pushing the comet into a new course.

Comets can have multiple tails. Usually, they have a blue tail, which is made up of ionised gases (their atoms have been stripped of their electrons by the solar wind). These atoms get all excited by the Sun’s radiation and emit blue light. This tail always points away from the Sun.

Another tail is made of dust and gas that, because it contains more mass than the ion tail, can be dragged behind the comet and curve slightly.

A successful hunter is a patient hunter, but don’t be too patient or your prize will vanish before your eyes. Because comets are essentially giant lumps of ice, every time they pass the Sun, they melt a little bit. All the gas that makes a comet so spectacular is actually its life blood venting away into space. Some comets can lose hundreds of tonnes of material a second so, eventually, all the ice and gas that holds them together will be gone and your comet will disintegrate.

Happy hunting!

 

 

 

 

 

Is Venus’ Rotation Slowing Down?

 

 

New measurements from ESA’s Venus Express spacecraft shows that Venus’ rotation rate is about 6.5 minutes slower than previous measurements taken 16 years ago by the Magellan spacecraft. Using infrared instruments to peer through the planet’s dense atmosphere, Venus Express found surface features weren’t where the scientists expected them to be.

“When the two maps did not align, I first thought there was a mistake in my calculations as Magellan measured the value very accurately, but we have checked every possible error we could think of,” said Nils Müller, a planetary scientist at the DLR German Aerospace Centre, lead author of a research paper investigating the rotation.

Venus Express in orbit since 2006 around our nearest planetary neighbor. Credits: ESA

Using the VIRTIS infrared instrument, scientists discovered that some surface features were displaced by up to 20 km from where they should be given the accepted rotation rate as measured by the Magellan orbiter in the early 1990s.

Over its four-year mission, Magellan determined the length of the day on Venus as being equal to 243.0185 Earth days. But the data from Venus Express indicate the length of the Venus day is on average 6.5 minutes longer.

What could cause the planet to slow down? One possibility may be the raging weather on Venus. Recent atmospheric models have shown that the planet could have weather cycles stretching over decades, which could lead to equally long-term changes in the rotation period. The most important of those forces is due to the dense atmosphere – more than 90 times the pressure of Earth’s and high-speed weather systems, which are believed to change the planet’s rotation rate through friction with the surface.

Earth experiences a similar effect, where it is largely caused by wind and tides. The length of an Earth day can change by roughly a millisecond and depends seasonally with wind patterns and temperatures over the course of a year.

But a change of 6.5 minutes over a little more than a decade is a huge variation.

Other effects could also be at work, including exchanges of angular momentum between Venus and the Earth when the two planets are relatively close to each other. But the scientists are still working to figure out the reason for the slow down.

These detailed measurements from orbit are also helping scientists determine whether Venus has a solid or liquid core, which will help our understanding how the planet formed and evolved. If Venus has a solid core, its mass must be more concentrated towards the center. In this case, the planet’s rotation would react less to external forces.

“An accurate value for Venus’ rotation rate will help in planning future missions, because precise information will be needed to select potential landing sites,” said Håkan Svedhem, ESA’s Venus Express project scientist.

Venus Express will keep monitoring the planet to determine if the rate of rotation continues to change.

 

 

 

 

 

STEREO Looks at the Sun; Finds Planets

 

STEREO spacecraft. Credit: NASA

The primary mission of the twin STEREO probes is to explore the 3-dimensional makeup of our Sun. Each craft carries a variety of instruments. One of them, the Heliospheric Imager (HI), doesn’t look directly at the Sun, but rather, explores a wide field near the Sun in order to explore the physics of coronal mass ejections (CMEs), in particular, ones aimed at theEarth. But while not focusing on solar ejections, the HI is free to make many other observations, including its first detection of an extrasolar planet.

As the Heliospheric Imager stares at the space between the Earth and Sun, it has made many novel observations. The device first opened its shutters in 2006 the instrument has observed the interaction of CMEs with the atmosphere of Venus, the stripping of a tail of a comet by a CME, atomic iron in a comet’s tail, and “the very faint optical emission associated with so-called Corotating Interaction Regions (CIRs) in interplanetary space, where fast-flowing Solar wind catches up with slower wind regions.”

The spacecraft allows for long periods of time to stare at patches of sky as the satellites precede and follow Earth in its orbit. The spacecraft is able to take pictures roughly every 40 minutes for almost 20 days in a row giving excellent coverage. As a result, the images taken have the potential to be used for detailed survey studies. Such information is useful for conducting variable star studies and a recent summary of findings from the mission reported the detection of 263 eclipsing variable stars, 122 of which were not previously classified as such.

Another type of variable star observed by the STEREO HI, was the cataclysmic sort, in particular, V 471 Tau. This red giant/white dwarf binary in the Hyades star cluster is a strong source of interest for stellar astrophysicists because the system is suspected to be a strong candidate for a type Ia supernova as the red giant dumps mass onto its high mass, white dwarf companion. The star system is extremely erratic in its light output and observations could help astronomers understand how such systems evolve.

Although planetary hunting is at the very edge of the capabilities of the HI’s limitations, eclipses caused by planet sized objects are feasible for many of the brighter stars in the field of view as dim as approximately 8th magnitude. Around one star, HD 213597, the STEREO team reported the detection of an object that seems too small to be a star based on the light curve alone. However, follow up studies will be necessary to pin down the object’s mass more accurately.

 

 

 

 

 

IBEX: Glimpses of the Interstellar Material Beyond our Solar System [NASA]

 

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IBEX has directly sampled multiple heavy elements from the Local Interstellar Cloud for the first time. Credit: NASA/Goddard Space Flight Center

A great magnetic bubble surrounds the solar system as it cruises through the galaxy. The sun pumps the inside of the bubble full of solar particles that stream out to the edge until they collide with the material that fills the rest of the galaxy, at a complex boundary called the heliosheath. On the other side of the boundary, electrically charged particles from the galactic wind blow by, but rebound off the heliosheath, never to enter the solar system. Neutral particles, on the other hand, are a different story. They saunter across the boundary as if it weren't there, continuing on another 7.5 billion miles for 30 years until they get caught by the sun's gravity, and sling shot around the star.

There, NASA's Interstellar Boundary Explorer lies in wait for them. Known as IBEX for short, this spacecraft methodically measures these samples of the mysterious neighborhood beyond our home. IBEX scans the entire sky once a year, and every February, its instruments point in the correct direction to intercept incoming neutral atoms. IBEX counted those atoms in 2009 and 2010 and has now captured the best and most complete glimpse of the material that lies so far outside our own system.

The results? It's an alien environment out there: the material in that galactic wind doesn't look like the same stuff our solar system is made of.

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Neutral atoms from the galactic wind sweep past the solar system's magnetic boundary, the heliosheath, and travel some 30 years into our solar system toward the sun. NASA's Interstellar Boundary Explorer (IBEX) can observe those atoms and provide information about the mysterious neighborhood outside our home. Credit: NASA/Goddard Conceptual Image Lab

"We've directly measured four separate types of atoms from interstellar space and the composition just doesn't match up with what we see in the solar system," says Eric Christian, mission scientist for IBEX at NASA's Goddard Space Flight Center in Greenbelt, Md. "IBEX's observations shed a whole new light on the mysterious zone where the solar system ends and interstellar space begins."

More than just helping to determine the distribution of elements in the galactic wind, these new measurements give clues about how and where our solar system formed, the forces that physically shape our solar system, and even the history of other stars in the Milky Way.

In a series of science papers appearing in the Astrophysics Journal on January 31, 2012, scientists report that for every 20 neon atoms in the galactic wind, there are 74 oxygen atoms. In our own solar system, however, for every 20 neon atoms there are 111 oxygen atoms. That translates to more oxygen in any given slice of the solar system than in the local interstellar space.


"Our solar system is different than the space right outside it and that suggests two possibilities," says David McComas the principal investigator for IBEX at the Southwest Research Institute in San Antonio, Texas. "Either the solar system evolved in a separate, more oxygen-rich part of the galaxy than where we currently reside or a great deal of critical, life-giving oxygen lies trapped in interstellar dust grains or ices, unable to move freely throughout space." Either way, this affects scientific models of how our solar system – and life – formed.

Studying the galactic wind also provides scientists with information about how our solar system interacts with the rest of space, which is congruent with an important IBEX goal. Classified as a NASA Explorer Mission -- a class of smaller, less expensive spacecraft with highly focused research objectives -- IBEX's main job is to study the heliosheath, that outer boundary of the solar system's magnetic bubble -- or heliosphere -- where particles from the solar wind meet the galactic wind.

Previous spacecraft have already provided some information about the way the galactic wind interacts with the heliosheath. Ulysses, for one, observed incoming helium as it traveled past Jupiter and measured it traveling at 59,000 miles per hour. IBEX's new information, however, shows the galactic wind traveling not only at a slower speed -- around 52,000 miles per hour -- but from a different direction, most likely offset by some four degrees from previous measurements. Such a difference may not initially seem significant, but it amounts to a full 20% difference in how much pressure the galactic wind exerts on the heliosphere.


"Measuring the pressure on our heliosphere from the material in the galaxy and from the magnetic fields out there," says Christian, "will help determine the size and shape of our solar system as it travels through the galaxy."


These IBEX measurements also provide information about the cloud of material in which the solar system currently resides. This cloud is called the local interstellar cloud, to differentiate it from the myriad of particle clouds throughout the Milky Way, each traveling at different speeds. The solar system and its heliosphere moved into our local cloud at some point during the last 45,000 years.

Since the older Ulysses observations of the galactic wind speed was in between the speeds expected for the local cloud and the adjacent cloud, researchers thought perhaps the solar system didn't lie smack in the middle of this cloud, but might be at the boundary, transitioning into a new region of space. IBEX's results, however, show that we remain fully in the local cloud, at least for the moment.

"Sometime in the next hundred to few thousand years, the blink of an eye on the timescales of the galaxy, our heliosphere should leave the local interstellar cloud and encounter a much different galactic environment," McComas says.

In addition to providing insight into the interaction between the solar system and its environment, these new results also hold clues about the history of material in the universe. While the big bang initially created hydrogen and helium, only the supernovae explosions at the end of a giant star's life can spread the heavier elements of oxygen and neon through the galaxy. Knowing the amounts of such elements in space can help map how the galaxy has evolved and changed over time.

"This set of papers provide many of the first direct measurements of the interstellar medium around us," says McComas. "We've been trying to understand our galaxy for a long time, and with all of these observations together, we are taking a major step forward in knowing what the local part of the galaxy is like."


Voyager 1 could cross out of our solar system within the next few years. By combining the data from several sets of NASA instruments – Ulysses, Voyager, IBEX and others – we are on the precipice of stepping outside and understanding the complex environment beyond our own frontier for the first time.

The Southwest Research Institute developed and leads the IBEX mission with a team of national and international partners. The spacecraft is one of NASA's series of low-cost, rapidly developed missions in the Small Explorers Program. NASA's Goddard Space Flight Center in Greenbelt, Md., manages the program for the agency's Science Mission Directorate.

 

Most Detailed Look Ever Into the Carina Nebula

 

This broad panorama of the Carina Nebula, a region of massive star formation in the southern skies, was taken in infrared light using the HAWK-I camera on ESO’s Very Large Telescope. Many previously hidden features, scattered across a spectacular celestial landscape of gas, dust and young stars, have emerged. Credit: ESO/T. Preibisch

Like finding buried treasure, this new image of the Carina Nebula has uncovered details not seen before. This vibrant image, from ESO’s Very Large Telescope shows not just the brilliant massive stars, but uncovers hundreds of thousands of much fainter stars that were previously hidden from view. Hundreds of individual images have been combined to create this picture, which is the most detailed infrared mosaic of the nebula ever taken and one of the most dramatic images ever created by the VLT.

A color composite in visible light of the Carina Nebula. Credit: ESO/Digitized Sky Survey 2. Acknowledgment: Davide De Martin.

Although this nebula is spectacular when seen through telescopes, or in normal visible-light pictures, many of its secrets are hidden behind thick clouds of dust. Using HAWK-I infrared camera along with the VLT, many previously hidden features have emerged from the murk. One of the main goals of the astronomers, led by Thomas Preibisch from the University Observatory, Munich, Germany, was to search for stars in this region that were much fainter and less massive than the Sun. The image is also deep enough to allow the detection of young brown dwarfs.

The dazzling but unstable star Eta Carinae appears at the lower left of the new picture. This star is likely to explode as a supernova in the near future, by astronomical standards. It is surrounded by clouds of gas that are glowing under the onslaught of fierce ultraviolet radiation. Across the image there are also many compact blobs of dark material that remain opaque even in the infrared. These are the dusty cocoons in which new stars are forming.

The Carina Nebula lies about 7,500 light-years from Earth in the constellation of Carina.

This video zooms in on the new infrared view of the Carina Nebula:

 

 

 

 

 

Vostok: The lake that time forgot

 

We often hear remote areas being referred to as ‘untouched by man’, or as an ‘unspoiled wilderness’ but, by the very nature of mankind’s effect on the planet, such descriptions are (sadly) untrue. If it is open to the air, or watered by rivers, something of man will be imprinted upon it. There are no unspoiled environments left.

But what if we found a place that had been locked away from our influence – a bubble of untouched wilderness – a lost world?

Well, such a place does exist and, in the most remote region our planet, scientists are poised to take a first peek at its secrets.

Beneath four kilometres of Antarctic icesheet, Lake Vostok has been sealed away and isolated from the rest of the planet for almost 20 million years.

It is thought that the lake formed about 30million years ago, when Antarctica enjoyed a temperate climate. Then, about 20-15 million years ago, the climate suddenly cooled and glaciers formed in the mountains around Vostok. The ice sheets rolled down the mountains and across Lake Vostok – sealing it like the lid of giant sarcophagus.

Now, 20,000 millennia after the lake last saw the light of day and after more than 20 years of drilling, a team of Russian scientists are preparing to break the seal on this ‘lake that time forgot’. And they are hoping to find life.

When the lake formed, it would have been teeming with life – just as any body water in a temperate climate does. But, as the ice sheet formed over head, it would have slowly shut out the Sun’s light. As it darkened, plant life would have perished and large animal life would have quickly followed. So what are they hoping to find?

If there is any life left in Vostok it is likely to be microbial – extremely hardy bacteria that can survive extremes of temperature and (most importantly) survive without sunlight to fuel their growth.

In the absence of sunlight, these microbes would have to survive on chemicals pushed out from hydrothermal vents (hot springs) such as hydrogen sulphide. But such springs only occur in areas that are geologically active – where the Earth’s internal heat can escape to the surface and it has long been thought Antarctica is dead, geologically speaking, but new studies suggest that that this may not be the case beneath Lake Vostok.

If the area beneath the lake is still geologically active, there could be hot springs feeding life in lake’s depths. If they are there, the chances of finding life more complex than microbes increases.

Bacteria may not sound particularly exciting, but any microbial life that scientists do find will have been isolated from the rest of the planet for up to 20 million years. Entirely new species that bear no resemblance to the rest of life on Earth could have evolved and they, in turn, could give us an insight into how life evolved on our planet in the first place.

But the project isn’t without its problems. In order to investigate an untouched environment, you have to touch it and with that comes the risk of contamination. And the risk of contamination from the Russian hole is huge.

When they started drilling in 1990, scientists weren’t looking for a lake –  they were there to study the hundreds of thousands of years of climate data locked in the ice sheet. There were there to extract ice cores and preventing contamination wasn’t a priority. To keep their borehole from refrezzing, Russian engineers have used some 65 tonnes of oil-based kersone and, if some of that got into the lake, it could have a catastrophic effect on its ecosystem. There is also the risk that bacteria from the surface could hitch a ride on the drill and contaminate the system.

With this in mind, Nasa are formulating their own plans. They are developing a remote-controlled robotic laboratory that would squeeze spectrometers, microscopes, lights and cameras into a robot the size of a old-fashioned washing-up liquid bottle. It would, of course, need to be completely sterile, which rules out the hole drilled by Russia. So Nasa would have to drill their own hole. Let’s hope it doesn’t take them another 20 years.

 

 

The Milky Way’s Magnetic Personality

 

The sky map of the Faraday effect caused by the magnetic fields of the Milky Way. Red and blue colors indicate regions of the sky where the magnetic field points toward and away from the observer, respectively. The band of the Milky Way (the plane of the Galactic disk) extends horizontally in this panoramic view. The center of the Milky Way lies in the middle of the image. The North celestial pole is at the top left and the South Pole is at the bottom right. (Image Credit: Max Planck Institute for Astrophysics)

Recently we took a look at a very unusual type of map – the Faraday Sky. Now an international team of scientists, including those at the Naval Research Laboratory, have pooled their information and created one of the most high precision maps to date of the Milky Way’s magnetic fields. Like all galaxies, ours has a magnetic “personality”, but just where these fields come from and how they are created is a genuine mystery. Researchers have always simply assumed they were created by mechanical processes like those which occur in Earth’s interior and the Sun. Now a new study will give scientists an even better understanding about the structure of galactic magnetic fields as seen throughout our galaxy.

The team, led by the Max Planck Institute for Astrophysics (MPA), gathered their information and compiled it with theoretical simulations to create yet another detailed map of the magnetic sky. As NRL’s Dr. Tracy Clarke, a member of the research team explains, “The key to applying these new techniques is that this project brings together over 30 researchers with 26 different projects and more than 41,000 measurements across the sky. The resulting database is equivalent to peppering the entire sky with sources separated by an angular distance of two full moons.” This huge amount of data provides a new “all-sky” look which will enable scientists to measure the magnetic structure of the Milky Way in minute detail.

 

In this map of the sky, a correction for the effect of the Galactic disk has been made in order to emphasize weaker magnetic field structures. The magnetic field directions above and below the disk seem to be diametrically opposed, as indicated by the positive (red) and negative (blue) values. An analogous change of direction takes place across the vertical center line, which runs through the center of the Milky Way. (Image Credit: Max Planck Institute for Astrophysics)

Just what’s so “new” about this map? This time we’re looking at a quantity called Faraday depth – an idea dependent on a line-of-sight information set on the magnetic fields. It was created by combining more than 41,000 singular measurements which were then combined using a new image reconstruction method. In this case, all the researchers at MPA are specialists in the new discipline of information field theory. Dr. Tracy Clarke, working in NRL’s Remote Sensing Division, is part of the team of international radio astronomers who provided the radio observations for the database. It’s magnetism on a grand scale… and imparts even the smallest of magnetic features which will enable scientists to further understand the nature of galactic gas turbulence.

 

The concept of the Faraday effect isn’t new. Scientists have been observing and measuring these fields for the last century and a half. Just how is it done? When polarized light passes through a magnetized medium, the plane of the polarization flips… a process known as Faraday rotation. The amount of rotation shows the direction and strength of the field and thereby its properties. Polarized light is also generated from radio sources. By using different frequencies, the Faraday rotation can also be measured in this alternative way. By combining all of these unique measurements, researchers can acquire information about a single path through the Milky Way. To further enhance the “big picture”, information must be gathered from a variety of sources – a need filled by 26 different observing projects that netted a total of 41,330 individual measurements. To give you a clue of the size, that ends up being about one radio source per square degree of sky!

 

The uncertainty in the Faraday map. Note that the range of values is significantly smaller than in the Faraday map (Fig. 1). In the area of the celestial south pole, the measurement uncertainties are particularly high because of the low density of data points. (Image Credit: Max Planck Institute for Astrophysics)

Even with depth like this, there are still areas in the southern sky where only a few measurements have been cataloged. To fill in the gaps and give a more realistic view, researchers ” have to interpolate between the existing data points that they do have recorded.” However, this type of data causes some problems with accuracy. While you might think the more exact measurements would have the greatest impact on the map, scientists aren’t quite sure how reliable any single measurement could be – especially when they could be influence by the environment around them. In this case, the most accurate measurements don’t always rank the highest in mapping points. Like Heisenberg, there’s an uncertainty associated with the process of obtaining measurements because the process is so complex. Just one small mistake could led to a huge distortion in the map’s contents.

 

Thanks to an algorithm crafted by the MPA, scientists are able to face these types of difficulties with confidence as they put together the images. The algorithm, called the “extended critical filter,” employs tools from new disciplines known as information field theory – a logical and statistical method applied to fields. So far it has proven to be an effective method of weeding out errors and has even proven itself to be an asset to other scientific fields such as medicine or geography for a range of image and signal-processing applications.

Even though this new map is a great assistant for studying our own galaxy, it will help pave the way for researchers studying extragalactic magnetic fields as well. As the future provides new types of radio telescopes such as LOFAR, eVLA, ASKAP, MeerKAT and the SKA , the map will be a major resource of measurements of the Faraday effect – allowing scientists to update the image and further our understanding of the origin of galactic magnetic fields.

Original Story Source: Naval Research Laboratory News.

 

Can We Land On a Comet?

 

Science Casts: Mission to Land on a Comet *720P* [HD]

The Rosetta mission will do something never before attempted: land on a comet. The spacecraft is now on its way to intercept comet 67P/Churyumov-Gerasimenko in January 2014 and land a probe on it for what promises to be an amazing view. But what we know of comets so far comes from a few flyby missions. So, with surface composition and conditions largely a mystery, so how did engineers prepare to land on something that could be either solid ice or rock, or a powdery snow or regolith – or something in between?

They had to design the Philae lander so it could land equally well on any surface. In the tiny gravitational field of a comet, landing on hard icy surface might cause Philae to bounce off again. Alternatively, hitting a soft snowy one could result in it sinking. To cope with either possibility, Philae will touch as softly as possible. In fact, engineers have likened it more to docking in space.

Philae will fire harpoons to secure itself to the comet; additionally, the landing gear is equipped with large pads to spread its weight across a broad area (kind of like snowshoes.)

While landing on a comet will certainly be nail-biting, having a front row seat for when the comet gets closer to the Sun is the most highly anticipated part of the mission.

An artist concept of the Philae lander on comet 67P/Churyumov-Gerasimenko. Credit: Astrium - E. Viktor/ESA

“In some ways, a flyby is just a tantalizing glimpse of a comet at one stage in its evolution,” says Claudia Alexander, project scientist for the U.S. Rosetta Project at JPL. “Rosetta is different. It will orbit 67P for 17 months. We’ll see this comet evolve right before our eyes as we accompany it toward the Sun and back out again.”

We’ll be able to watch as it becomes “something poetic and beautiful, trailing a vast tail,” said Alexander. For once, we’ll be able to watch the surface of a comet transform in front of our eyes instead of relying on artist concept drawings! Additionally, the Rosetta spacecraft up above will be busy mapping the comet’s surface and magnetic field, monitoring the comet’s erupting jets and geysers, measuring outflow rates, and much more. Together, the orbiter and lander will build up the first 3-D picture of the layers and pockets under the surface of a comet.

Comets are considered a gold mine for astronomers who want to know what conditions were like back in the early days of our Solar System. And the data and images from this mission promises to be some of the most stunning we’ve yet seen.

 

Toronto Teens Launch “Lego Man in Space”

  

Two Toronto Teens Launch 'Lego Man In Space' to the Stratosphere - Jan 2012
Stunning space imagery was captured by Canadian teenagers Mathew Ho and Asad Muhammad when they lofted a tiny ‘Lego Man in Space’ astronaut to an altitude of 16 miles (25 kilometers) precariosuly protruding from a helium filled weather balloon. Lego Man is holding the Canadian National flag. Earth's curvature and blackness of space in background. Credit: Mathew Ho and Asad Muhammad
See the Video and Photos below - Lego Man even shoots the Moon

Two teens from Toronto,Canada have launched “Lego Man in Space” using a helium filled weather balloon and captured stunning video of the miniature toy figure back dropped by the beautiful curvature of Earth and the desolate blackness of space that’s become a worldwide YouTube sensation.

17 year olds Mathew Ho and Asad Muhammad lofted the tiny 2 inch tall Lego figure from a local Toronto soccer field up to a height of about 85,000 feet, or 16 miles (25 kilometers), where the 22 foot (7 m) diameter helium balloon burst in what is technically known as the stratosphere. The homemade styrofoam capsule – equipped with two video cameras and four digital cameras – then parachuted back to Earth.

“After endless hours of hard work, we managed to capture stunning views of our atmosphere and put a ‘Lego’ man into near space!” said the ambitious teens who are 12th graders at the Agincourt Collegiate Institute.

The pair posted a YouTube video (below) documenting the entire voyage and some camera snapshots on their website on January 25.

Lego Man even snapped cool Moon shots – look closely at the video and photo below.

“Lego Man in Space” – The Video

The duo recounted the details of their sensational space tale of science on a shoestring for Canadian TV and newspapers.

“Upon launch we were very relieved. But we had a lot of anxiety on launch day because there were high winds when we were going up after all the hard work,” said Ho in an interview on Canadian TV (CTV).

“We were also scared because now we would have to retrieve it back after it came down,” said Asad.

“We had no idea it would capture photos like that and would be so good,” said Ho. “We were blown away when we saw them back home.”

The toy Lego astronaut is seen standing atop a thin runway protruding precariously from one end of the small, box shaped capsule as though he was walking the plank and about to plunge into the ocean of space. All the while, cameras were aimed directly out towards him recording the entire rollicking journey from liftoff to the stratosphere to landing, with a constantly changing Earth in the background.

Altogether they netted two videos and 1500 photos.

Lego Man in Space shoots the Moon !
Credit: Mathew Ho and Asad Muhammad

Coincidentally, several Lego toys are constantly flying even higher above the Earth at this very moment aboard the International Space Station as part of an educational outreach effort by NASA and Lego.

Legoman’s spectacular journey lasted some 97 minutes. He’s beaming proudly throughout the video while holding the Canadian National flag – the Red Maple Leaf. The rollercoaster-like scenery may well challenge the stomachs of those with fear of heights.

The tumbling Lego Man in Space capsule upon the violent descent captured the moment before the parachute was activated. Credit: Mathew Ho and Asad Muhammad

Mathew and Asad worked over about four months one day a week on Saturdays to assemble the rig in Mathew’s kitchen and successfully accomplished the feat on a shoestring budget of merely 400 dollars. They used GPS trackers to locate “Lego Man in Space” and recover the intact capsule holding the imagery.

After the balloon burst, the parachute assisted descent back to Earth took about 32 minutes. Winds aloft caused the capsule to drift some 76 miles (122 kilometers) away from the launch site before landing at Rice Lake in one piece.

Lego Man in Space capsule after landing 76 miles (122 kilometers) away from the Toronto soccor field launch site. Credit: Mathew Ho and Asad Muhammad

“We were jumping for joy when we saw the capsule and the parachute. We were ecstatic when we found it,” said Ho.

They were inspired by MIT students who sent a camera to the edge of space with a balloon two years ago and captured stunning views.

“We have a long history of passionate building and working together,” Ho told CTV.

And now we know another truth about Lego’s – Not only can they withstand the destructive forces of kids, but outer space too !

Astronomers aim to 'capture' a black hole

French astronomer Pierre-Simon Laplace predicted the existence of black holes way back in 1796, but we’ve yet to capture one on camera. The Event Horizon Telescope will bring together astronomy’s greatest radio telescopes in an attempt ‘photograph’ the supermassive black hole at the heart of the Milky Way

Where would science fiction be without black holes? As a plot device they are without equal. They can imperil our plucky hero as his spacecraft is sucked like a spider down a plughole to (almost) certain doom and they provide a handy shortcut to the past, or future, in the form of a wormhole. But despite their ubiquity in TV and film, astronomers have never actually seen one.

In fact, everything we know of black holes comes from theory and indirect observations of the effects they have on the space around them. But now scientists are getting ready to take their first picture of these enigmatic phenomena.

To tackle this monumental task they will create a global network of some of the planet’s greatest radio telescopes to create a colossal virtual telescope the size of planet Earth.

Astronomers and scientists from across the world met last week to discuss the project, which has been dubbed ‘The Event Horizon Telescope’. They hope to enlist the talents of telescopes in Arizona, Hawaii, California, Europe, Mexico, Chile and the South Pole. In all 50 radio telescopes will be involved. A technique called interferometry will allow the Earth-size network to act like a single Earth-size telescope.

Its task will be to capture an image of the black hole that hides at the centre of our galaxy, the Milky Way. But that isn’t as easy as it sounds.

Even though it is classed as a supermassive black hole that weighs in at an impressive four million times the mass of our Sun, it is extremely compressed and is almost 26,000 light-years away. Its very nature, which prevents anything (including light) from escaping, makes it impossible to image the black hole directly.

Instead, the Event Horizon Telescope will aim to photograph the swirling disk of matter and energy that surrounds the black hole. By looking for the point at which the black hole’s gravity becomes so intense that it prevents anything from escaping (called the event horizon) scientists will get an outline of this most enigmatic of cosmic phenomena.

But best of all, it's given me an excuse to talk about black holes and (as we all know) black holes rock!

The weird and wonderful black hole: A most singular singularity...

Black holes are birthed in the death throes of a large star (about 25 times the mass of our Sun is perfect). Stars rely on the heat created by nuclear fusion to remain stable. When their hydrogen fuel supply is exhausted, they throw off their remaining gases in a supernova explosion – leaving behind only their super-dense core. The core remnant then collapses under the force of its own gravitation

The core remnant keeps collapsing until it is smaller than an atom. In fact, it will become smaller than the smallest piece of all the impossibly small things that make up an atom – known as a singularity. If you imagine that a grain of salt might measure in at 0.0001 metres, to describe the size of the singularity you would have to stick 35 zeros in front of that number one... which looks like this 0.00000000000000000000000000000000001 metres – and remember, that impossibly small speck has the mass of several Suns squashed up inside it

Although the singularity is the gravitational engine of a black hole, it doesn’t define it. A black hole is defined by the region around the singularity where its gravity is felt so strongly that not even light can escape its pull. The point at which light can longer escape is called the event horizon and this defines the limits of the black hole

At the centre of a black hole, spacetime is infinitely curved and matter is crushed to infinite density under the pull of 'infinite' gravity. At a singularity, the laws of physics (as we know them) break down and space and time cease to exist

Just like planets, galaxies and pretty much everything in the universe, black holes spin. Black holes are formed from stars and all stars rotate. When a star’s core starts to collapse, the star’s rotation speeds up (think of a spinning ice-skater tucking his arms in to speed up the spin). As the star’s core shrinks to become a black hole its spin get faster and faster. Unfortunately, we can’t know how fast a black hole spins, but you can guess that its pretty fast – a neutron star (which is star that has collapsed to a few miles in diameter) can spin up to 1,000 times a second. So imagine how fast a star that has collapsed to a singularity is spinning.

The easiest way to describe how a black hole works is to imagine a very heavy ball sitting on a sheet of rubber. Just as a heavy ball makes an indent in the rubber, so a black hole makes an indent in the fabric of spacetime. Less massive objects fall into the indent – like water falling down a plug hole

But that’s a two-dimensional view of a black hole. In reality, spacetime isn’t a two-dimensional sheet – it is multidimensional – and gravity interacts with all these dimensions. This means that a black hole is more like a sphere, with a central point where spacetime is drawn to a focal point (the singularity) in the centre.
But it gets even more complicated than that. If the singularity is spinning, it twists the fabric of space around it (imagine a sheet getting caught up in drill bit)

Black holes aren’t fixed into one position in space – they wander around the universe. As they wander, they can blunder into other black holes and, if they get close enough, their mutual gravitational attraction causes them to begin orbiting each other. As they get closer, the speed of their orbit increases until they smash together – creating a much larger black hole. Black holes can also devour stars by stripping them of matter. Eventually a black hole will absorb enough of its brethren and other stars to become a supermassive black hole - one with millions or even billions of times the mass of our Sun

According to Newton’s Laws, gravity depends on distance – the closer you get to an object, the stronger you feel the effect of its gravity. This effect is exaggerated near a black hole. If you were able to get close enough to a black hole, the difference in gravity felt between your feet and you head would be colossal. In fact, the difference is so extreme that your feet would feel many hundreds of millions of times more gravity than your head. This would result in you becoming stretched into a long, thin strand (imagine holding a lump of Blu-Tack with both hands and pulling as hard as you can). This is called ‘spaghettification

 

Space 2012: A big year for private space flight

 


Historically space has been a nationalistic pursuit – as much driven by pride and paranoia as by the spirit of exploration and curiousity. For 50 years, space was ‘owned’ by governments, but the sun is setting on the age of space nationalism and is rising anew to greet an age of space capitalism. Private companies powered by idealistic entrepreneurs seeking the democratisation of space and (of course) driven by profit are pushing aside big government’s grip on the final frontier. A revolution is coming and space is set to claimed by the people.

It could be that, when our space-faring descendants look back on the moment that space travel really took off, 2012 is the year that their history books will celebrate.

Even now, the astronauts living on the International Space Station are gearing up for a milestone event in February – the first visit of a commercial spacecraft to their orbiting outpost.

Private spaceflight company, SpaceX, plans to launch its unmanned Dragon capsule on February 7 onboard their very-own rocket booster – the Falcon 9. Carrying food, clothing and other supplies, the craft’s mission is pretty mundane but it will be the first time that a craft not owned by a government has made such a trip – and it’s a task that the once mighty Nasa is increasingly reliant upon, since the retirement of the Space Shuttle programme.

In the true spirit of capitalism, SpaceX won’t have things to themselves for very long. Other firms will be testing their own space vehicles in 2012 with goal of performing similar tasks – as well as achieving loftier goals – in the coming years. Another American firm, the Sierra Nevada Corporation is building a mini-space plane called Dream Chaser. Resembling a sort of squashed Space Shuttle, Dream Chaser will initially supply the ISS but will also offer a commercial passenger service to and from orbit. The craft won’t be making any commercial flights this year but it will be undergoing crucial drop tests (to make sure all those fee-paying passengers don’t get barbequed on their return through Earth’s atmosphere).

Of course space isn’t all about orbits and re-entries – for many aspiring space tourists their first taste of ‘the big black’ will come in the form of sub-orbital flights. These flights will cheaper, safer and quicker – more of an experience than an adventure. Arguably the most famous of the sub-orbital contenders is Virgin Galactic and their super-sexy SpaceShipTwo craft. For them 2012 will be a pivotal year. As well as continuing drop-tests, the firm hope to finally power up their hybrid rocket for a proper flight test. It has been rumoured that the rocket has been plagued with problems (which is pretty much par for the course with any new technology) but a successful flight test this year will pave the way for tourist flights to begin in 2013.

Elsewhere, XCOR’s single-passenger craft, Lynx, looks to be making good progress and will continue testing in 2012 and it could be a close race between them and Virgin to see who will be first to fly fee paying customers to suborbital space.

Ok, with many companies projecting flights starting in 2013, perhaps 2012 won’t be the red-letter day in the history of private space flight, but it will be the year that commercial space enterprise goes from being a dream to becoming, at the very least, an imminent reality. And that’s got to be worth celebrating.

 

Tracing Dark Matter with Ripples in the Whirlpool Galaxy

 

M51

[The distribution of HI hydrogen in the Whirlpool Galaxy (M51) as determined by the THINGS VLA survey extends far beyond the visible stars in the galaxy and its satellite NGC 5195 (marked by cross), which is situated in the short arm of the spiral. Analysis of perturbations in the hydrogen distribution can be used to predict the location of such satellites, in particular, those satellites that are composed primarily of dark matter and are thus too faint to be detected easily. ]

A new paper presented at this week’s American Astronomical Society conference promises to shine some light, so to speak, on the pursuit of dark matter in individual galaxies. The current model of cold dark matter in the Universe is extremely successful when it comes to mapping the mysterious substance on large scales, but not on galactic and sub-galactic scales. Earlier today, Dr. Sukanya Chakrabarti of Florida Atlantic University described a new way to map dark matter by observing ripples in the hydrogen disks of large galaxies. Her work may finally allow astronomers to use their observations of ordinary matter to probe the distribution of dark matter on smaller scales.

 

Spiral galaxies are typically composed of a disk, which is made of normal (baryonic) matter and contains the central bulge and spiral arms, and a halo, which surrounds the disk and contains dark matter. In recent years, surveys such as THINGS (conducted by the NRAO Very Large Array) have been undertaken to analyze the distribution of hydrogen in nearby galactic disks. Last year, Dr. Chakrabarti used such surveys to investigate the way that small satellite galaxies affect the disks of larger galaxies such as M51, the Whirlpool Galaxy. But the real prize lies in investigating what astronomers cannot see. Chakrabarti remarked, “Since the 70s, we’ve known from observations of flat rotation curves that galaxies have massive dark matter halos, but there are very few probes that allow us to figure out how it’s distributed.” She has now broadened her research to do just that.

Astronomers believe that the density distribution of dark matter relies on a parameter called its scale radius. As it turns out, varying this parameter visibly affects the shape of the galaxy’s hydrogen disk when the influence of passing dwarf galaxies is accounted for.

“Ripples in outer gas disks serve to act like a mirror of the underlying dark matter distribution,” said Chakrabarti. By varying the scale radius of M51′s dark matter halo, Chakrabarti was able to see how it would affect the shape and distribution of atomic hydrogen in its disk. She found that large scale radii give rise to galaxies with a dark matter halo that becomes gradually more diffuse as it extends along the length of the disk. This causes the hydrogen in the disk to be very loosely wrapped around the central bulge of the galaxy. Conversely, small scale radii have density profiles that fall off much more steeply.

“Steeper density profiles are more effective at holding onto their ‘stuff’,” explained Chakrabarti, “and therefore they have a much more tightly wrapped spiral planform.”

Chakrabarti’s map of the distribution of dark matter in the halo of M51 is consistent with existing theoretical models, leading her to believe that this method may be extremely useful for astronomers trying to probe the elusive, invisible substance that makes up almost a quarter of our Universe. A preprint of her paper is available on the ArXiv.

 

 

Amazing fact....

Unlocking Cosmology With Type 1a Supernovae

 

New research shows that some old stars known as white dwarfs might be held up by their rapid spins, and when they slow down, they explode as Type Ia supernovae. Thousands of these "time bombs" could be scattered throughout our Galaxy. In this artist's conception, a supernova explosion is about to obliterate an orbiting Saturn-like planet. Credit: David A. Aguilar (CfA)

Let’s face it, cosmologists catch a lot of flack. It’s easy to see why. These are people who routinely publish papers that claim to ever more finely constrain the size of the visible Universe, the rate of its breakneck expansion, and the distance to galaxies that lie closer and closer to the edges of both time and space. Many skeptics scoff at scientists who seem to draw such grand conclusions without being able to directly measure the unbelievable cosmic distances involved. Well, it turns out cosmologists are a creative bunch. Enter our star (ha, ha): the Type 1a Supernova. These stellar fireballs are one of the main tools astronomers use in order to make such fantastic discoveries about our Universe. But how exactly do they do it?

First, let’s talk physics. Type 1a supernovae result from a mismatched marriage gone wrong. When a red giant and white dwarf (or, less commonly, two white dwarfs) become trapped in a gravitational standoff, the denser dwarf star begins to accrete material from its bloated companion. Eventually the white dwarf reaches a critical mass (about 1.4 times that of our own Sun) and the natural pressure exerted by its core can no longer support its weight. A runaway chemical reaction occurs, resulting in a cataclysmic explosion so large, it can be seen billions of light years away. Since type 1a supernovae always result from the collapse of a white dwarf, and since the white dwarf always becomes unstable at exactly the same mass, astronomers can easily work out the precise luminosity of such an event. And they have. This is great news, because it means that type 1a supernovae can be used as so-called standard candles with which to probe distances in the Universe. After all, if you know how bright something is and you know how bright it appears from where you are, you can easily figure out how far away it must be.

A Type Ia supernova occurs when a white dwarf accretes material from a companion star until it exceeds the Chandrasekhar limit and explodes. By studying these exploding stars, astronomers can measure dark energy and the expansion of the universe. CfA scientists have found a way to correct for small variations in the appearance of these supernovae, so that they become even better standard candles. The key is to sort the supernovae based on their color. Credit: NASA/CXC/M. Weiss


Now here’s where cosmology comes in. Photons naturally lose energy as they travel across the expanding Universe, so the light astronomers observe coming from type 1a supernovae will always be redshifted. The magnitude of that redshift depends on the amount of dark energy that is causing the Universe to expand. It also means that the apparent brightness of a supernova (that is, how bright it looks from Earth) can be monitored to determine how quickly it is receding from our line of view. Observations of the night sky will always be a function of a specific cosmology; but because their distances can be so easily calculated, type 1a supernovae actually allow astronomers to draw a physical map of the expansion of the Universe.

 

Spotting a type 1a supernova in its early, explosive throes is a rare event; after all, the Universe is a pretty big place. But when it does happen, it offers observers an unparalleled opportunity to dissect the chaos that leads to such a massive explosion. Sometimes astronomers are even lucky enough to catch one right in our cosmic backyard, a feat that occurred last August when Caltech’s Palomar Transit Factory (PTF) detected a type 1a supernova in M101, a galaxy just 25 million light years away. By the way, it isn’t just professionals that got to have all the fun! Amateur and career astronomers alike were able to use this supernova (the romantically named PTF11kly) to probe the inner workings of these precious standard candles. Want to learn more about how you can get in on the action the next time around? Check out UT’s podcast, Getting Started in Amateur Astronomy for more information.

 

ECHOES FROM CARINAE'S GREAT ERUPTION

 

Eta Carinae Image: HSTDuring the mid 1800′s, the well known star η Carinae underwent an enormous eruption becoming for a time, the second brightest star in the sky. Although astronomers at the time did not yet have the technology to study one of the largest eruptions in recent history in depth, astronomers from the Space Telescope Science Institute recently discovered that light echoes are just now reaching us. This discovery allows astronomers to use modern instruments to study η Carinae as it was between 1838 and 1858 when it underwent its Great Eruption.

 

V838 Mon (Credit: NASA, European Space Agency and Howard Bond (STScI))

Light echoes have been made famous in recent years by the dramatic example of V838 Monocerotis. While V838 Mon looks like an expanding shell of gas, what is actually depicted is light reflecting off shells of gas and dust that was thrown off earlier in the star’s life. The extra distance the light had to travel to strike the shell, before being reflected towards observers on Earth, means that the light arrives later. In the case of η Carinae, nearly 170 years later!

 

The reflected light has its properties changed by the motion of the material off which it reflects. In particular, the light shows a notable blueshift, telling astronomers that the material itself is traveling 210 km/sec. This observation fits with theoretical predictions of eruptions similar to the type η Carinae is thought to have undergone. However, the light echo has also highlighted some discrepancies between expectation and observation.

Typically, η Carinae’s eruption is classified as a “supernova impostor”. This title is fitting since the eruptions create a large change in the overall brightness. However, although these events may release 10% of the total energy of a typical supernova or more, the star remains intact. The main model to explain such eruptions is that a sudden increase in the star’s energy output causes some of the outer layers to be blown off in an opaque wind. This shell of material is so thick, that it gives a large increase in the effective surface area from which light is emitted, thereby increasing the overall brightness.

However, for this to happen, models predict that the temperature of the star prior to the eruption needs to be at least 7,000 K. Analyzing the reflected light from the eruption places the temperature of η Carinae at the time of the eruption at a much lower 5,000 K. This would suggest that the favored model for such events is incorrect and that another model, involving an energetic blast was (a mini-supernova), may be the true culprit, at least in η Carinae’s case.

Yet this observation is somewhat at odds with observations made in the years following the eruption. As spectrography came into use, astronomers in 1870 visually noticed emission lines in the star’s spectrum which is more typical in hotter stars. In 1890, η Carinae had a smaller eruption and a photographic spectrum put the temperature around 6,000 K. While this may not accurately reflect the case of the Great Eruption, it is still puzzling how the star’s temperature could change so quickly and may also indicate that the favored model of the opaque-wind model is a better fit for later times or the smaller eruption, which would suggest two different mechanisms causing similar results in the same object on short timescales.

Either way, η Carinae is a marvelous object. The team has also identified several other areas in the shell surrounding the star which appear to be brightening and undergoing their own echoes which the team promises to continue to observe which would allow them to verify their findings.

 

Earth’s Other Moons

In the fall of 2006, observers at the Catalina Sky Survey in Arizona found an object orbiting the Earth. At first, it looked like a spent rocket stage — it had a spectrum similar to the titanium white paint NASA uses on rocket stages that end up in heliocentric orbits. But closer inspection revealed that the object was a natural body. Called 2006 RH120, it was a tiny asteroid measuring just a few metres across but it still qualified as a natural satellite just like the Moon. By June 2007, it was gone. Less than a year after it arrived, it left Earth’s orbit in search of a new cosmic companion.

 

Now, astrophysicists at Cornell are suggesting that 2006 RH120 wasn’t an anomaly; a second temporary moon is actually the norm for our planet.

Temporary satellites are a result of the gravitational pull of Earth and the Moon. Both bodies pull on one another and also pull on anything else in nearby space. The most common objects that get pulled in by the Earth-Moon system’s gravity are near Earth objects (NEOs) — comets and asteroids are nudged by the outer planets and end up in orbits that bring them into Earth’s neighbourhood.

Near Earth object Eros, the type of object that could be a second satellite. Image credit: NASA

The team from Cornell, astrophysicists Mikael Granvik, Jeremie Vaubaillon, Robert Jedicke, has modeled the way our Earth-Moon system captures these NEOs to understand how often we have additional moons and how long they stick around.

They found that the Earth-Moon system captures NEOs quite frequently. “At any given time, there should be at least one natural Earth satellite of 1-meter diameter orbiting the Earth,” the team said. These NEOs orbit the Earth for about ten months, enough time to make about three orbits, before leaving.

Luckily, and very interestingly, this discovery has implication well beyond academic applications.

Knowing that these small satellites come and go but that one is always present around the Earth, astronomers can work on detecting them. With more complete information on these bodies, specifically their position around the Earth at a given time, NASA could send a crew out to investigate. A crew wouldn’t be able to land on something a few metres across, but they could certainly study it up close and gather samples.

Close up image of asteroid 243 Ida. Image credit: NASA/courtesy of nasaimages.org

Proposals for a manned mission to an asteroid have been floating around NASA for years. Now, astronauts won’t have to go all the way out to an asteroid to learn about the Solar System’s early history. NASA can wait for an asteroid to come to us.

If the Cornell team is right and there is no shortage of second satellites around the Earth, the gains from such missions increases. The possible information about the solar system’s formation that we could obtain would be amazing, and amazingly cost-efficient.

Source: Earth Must Have Another Moon, Astronomers Say

 

Astrophotos: The Great Orion Nebula

M42 & M43 Orion Nebula Trapezium core by John ChumackThe Great Orion nebula is one of the brightest nebulae visible in the night sky. It is located about 1300 light years away in the southern part of the Orion’s belt.

 

We’ve collected several amazing images of the Great Orion nebula submitted by readers online. Here’s hoping that you’ll enjoy them as much as we did!

The image above was obtained by John Chumack from the high res close-up image of Trapezium taken with his 10” scope ( 30 sec., 1 minute, & 5 minutes) in his backyard in Dayton combined with the image taken using his homemade 16” scope data (10 minutes) taken at his observatory in Yellow Springs, Ohio.

“My image Data was captured in 2010 & 2011 and was then combined. I used my Modified Canon Rebel Xsi (Baader Filter) @ ISO 400, dark frames subtracted, and post processing in Adobe. Total exposure time for all Data was 16.5 minutes.

I processed it for the Trapezium’s core, I wanted to show all the small dark nebula / Dusty Bok Globules buried in that bright Zone, which is often over exposed in most images of this region!

It came out very detailed, especially the Trapezium region and its bright core stars which are also individually visible!”

More images below!

 

The Great Orion Nebula taken from Italy by Marco T.

The Great Orion Nebula taken from Italy. Image Credit: Marco T.


Marco T. captured this image using a Canon EOS 500D camera. Here are some specs he provided:
80x40sec 800iso – 31dark – 30bias temp. 6°c
SKYWATCHER ED80 PRO BLACK DIAMOND – camera guide QHY5
HIGH light pollution (Rome – Italy)

 

 

Orion Nebula by Kevin Jung

Orion Nebula. Image Credit: Kevin Jung


This image was taken by Kevin Jung at the James C. Veen Observatory in Lowell, Michigan. It was a stack of three individual 60-second exposures captured using a Canon EOS 40D camera.

 

 

Orion and Running Man Nebulae by Brendan Alexander

Orion and Running Man Nebulae. Image Credit: Brendan Alexander


Brendan Alexander took this image in Donegal, Ireland on January 6, 2011. He used a Celestron Omni XLT 150 telescope, Celestron CG5-GT (unguided) and a self-modified Canon 1000D. Here are a number of specs provided by Brendan:
Additional: Astronomik cls clip LP filter.
Stacking & Processing: DeepSkyStacker & Photoshop CS5
Exposure: 8 x Five minute exposures (20Darks). Core- 20x 90sec (10Darks), 20 x 30sec (20Darks) 20 x 8sec (20Darks) 40mins total exposure.

 

 

The Great Orion Nebula by Patrick Cullis

The Great Orion Nebula. Image Credit: Patrick Cullis


Patrick Cullis captured this image using a 4″ Meade SCT with 5D Mk II on Orion Sirius Equatorial Mount.

 

“A new go at the Orion Nebula. I used ten minute exposures this time, which brought out a lot more of the faint nebulosity, but blew out the trapezium stars.”

 

The Great Orion Nebula by Ken Lord

The Great Orion Nebula. Image Credit: Ken Lord


This photo was submitted to us by Ken Lord. He took this image on December 1, 2011 using a 190mm F5.3 Skywatcher Maksutov Newtonian telescope and Canon T1i DSLR at 30 seconds exposure and ISO 1600.

 

“Orion is high in the sky now, so I figured I’d see how it looks now with the darker skies at my new home.

It’s dark enough that I could use ISO1600 instead of 800 on a 30 second exposure and still have a lot less light pollution.

This is a JPG straight from the camera, not stacked, I shot 60x 30 second exposures, the CR2′s are still waiting to be stacked and processed.”

 

How Can Growing Galaxies Stay Silent?

 

The Andromeda Galaxy (M31) with minor satellite galaxy M32Beginning around 2005, astronomers began discovering the presence of very large galaxies at a distance of around 10 billion lightyears. But while these galaxies were large, they didn’t appear to have a similarly large number of formed stars. Given that astronomers expect galaxies to grow through mergers and mergers tend to trigger star formation, the presence of such large, undeveloped galaxies seemed odd. How could galaxies grow so much, yet have so few stars?

One of the leading propositions is that the galaxies have undergone frequent mergers, but each one was very small and didn’t encourage large scale star formation. In other words, instead of mergers between galaxies of similar size, large galaxies developed quickly and early in the universe, and then tended to accumulate through the integration of minor, dwarf galaxies. While this solution is straightforward, testing it is difficult since the galaxies in question are at vast distances and detecting the minor galaxies as they are devoured would require exceptional observations.

Seeking to test this hypothesis, a team of astronomers led by Andrew Newman from the California Institute of Technology combined observations from Hubble and the United Kingdom Infra-Red Telescope (UKIRT), to search for these diminutive companions. The team examined over 400 galaxies that didn’t display signs of active star formation (called “quiet” galaxies) in search of possible companion galaxies from distances of 10 billion light years to a relatively close 2 billion lightyears in order to determine how this minor merger rate has evolved over time.

From their study, they determined that around 15% of quiet galaxies had a nearby counterpart that had at least 10% the mass of the larger galaxy. This took into account the possibility that some galaxies may have been more distant but along the line of sight by ensuring that both galaxies had similar redshifts. Over time, the partner galaxies became rarer suggesting that they were becoming rarer as more were consumed by the larger brethren. Using this as a rate at which mergers must occur, the team was able to answer the question of whether or not these minor mergers could account for the galaxy growth discovered six years earlier.

For galaxies closer than a distance of roughly 8 billion light years, the rate of minor mergers was able to completely explain the overall growth of galaxies. However, for the growth rate of galaxies at times earlier than this, such minor mergers could only account for around half of the apparent growth.

The team proposes several reasons this may be the case. Firstly, many of the basic assumptions could be flawed. Teams may have overestimated the sizes of the massive galaxies, or underestimated the rate of star formation. These key properties were often derived from photometric surveys which are not as reliable as spectroscopic observations. In the future, if better observations can be made, these values may be revised and the problem may resolve itself. The other option is that there are simply additional processes at work that astronomers have yet to understand. Either way, the question of how growing galaxies avoid advertising their growth is unanswered.

 

New Plans for ESA’s Experimental Re-entry Vehicle

ESA’s new IXV (Intermediate eXperimental Vehicle) Credit: ESA


ESA and Arianespace have signed a contract planning the launch of ESA’s new IXV (Intermediate eXperimental Vehicle) on Europe’s new Vega Rocket in 2014. Vega is Europe’s new small launch system and it is designed to complement the heavy Ariane 5 and medium Soyuz Rocket systems launched from French Guiana.

The small rocket is capable of a wide range of payloads up to 1.5 tonnes, compared to Ariane 5 which can lift 20 tonnes, making it especially suitable for the commercial space market. The Vega Rocket will launch the IXV into a suborbital trajectory from Europe’s Spaceport in French Guiana, IXV will then return to Earth as if from a low-orbit mission, to test and qualify new critical technologies for future re-entry vehicles.

Vega Rocket Credit: Arianespace


The IXV will reach a velocity of 7.5km/s at an altitude of around 450km and then re-enter the Earth’s atmosphere gathering data about its flight. The vehicle will encounter hypersonic and supersonic speeds and will be controlled complex avionics, thrusters and flaps.

Once the vehicle’s speed has been reduced enough, it will deploy a parachute, descend and land safely in the Pacific Ocean.

This flight will record data for the next five VERTA missions (Vega Research and Technology Accompaniment – Programme), which will demonstrate the systems re-usable versatility.

Two launches a year are planned for the new programme and construction of infrastructure including mission control and communications networks is currently underway.

Development and completion of the design, manufacturing and assembly is now underway for a flight window between January and September 2014.

VERTA (Vega Research and Technology Accompaniment – Programme) Credit: Arianespace

In The Still Of The Night… Listening To The “Heartbeat” Of A Tiny Black Hole

Artist's rendering showing the jet fully established. Credit: NASA/Goddard Space Flight Center/CI Lab

Is everything quiet in deep space?  Not hardly.  It’s a place jammed with noises of all kinds.  So much noise, in fact, that it could be quite difficult to pick up a faint signature of something small…  something like the smallest black hole known.  Thanks to  NASA’s Rossi X-ray Timing Explorer (RXTE) , an international team of astronomers have found the pulse they were looking for and it’s a pattern that’s only been seen in one other black hole system.

Its name is IGR J17091-3624 and it’s a binary system which consists of a normal star and a black hole with a mass that measures only about three times solar.  In theoretical terms, that’s right at the edge where possibility of being a black hole begins.

Here’s the picture…  In this binary system, escaping gas from the “normal” star flows across space in the direction of the black hole.  This action creates a disk where friction heats it to millions of degrees – releasing X-rays.  Periodic changes in the strength of the X-ray emissions point towards the actions taking place within the gas disk.  Scientists theorize that fast changes occur at the event horizon… the point of no return.

IGR J17091-3624 was discovered when it went into outburst in 2003. Current observations have it becoming active every few years and its most recent flare began in February of this year and has been kicking up cosmic dust ever since. Observations place it in the general direction of Scorpius, but astronomers aren’t sure of an exact distance – somewhere between 16,000 light years to more than 65,000. However, IGR J17091-3624 isn’t absolutely alone in its unique changes. Black hole binary, GRS 1915+105, also displays a number of well-ordered rhythms, too.

This animation compares the X-ray ‘heartbeats’ of GRS 1915 and IGR J17091, two black holes that ingest gas from companion stars. GRS 1915 has nearly five times the mass of IGR J17091, which at three solar masses may be the smallest black hole known. A fly-through relates the heartbeats to hypothesized changes in the black hole’s jet and disk. Credit: NASA/Goddard Space Flight Center/CI Lab

“We think that most of these patterns represent cycles of accumulation and ejection in an unstable disk, and we now see seven of them in IGR J17091,” said Tomaso Belloni at Brera Observatory in Merate, Italy. “Identifying these signatures in a second black hole system is very exciting.”

Binary GRS 1915 has some very cool characteristics.  Right now astronomers have observed jets blasting out in opposite directions cruising along at 98% the speed of light.  These originate at the event horizon where strong magnetic fields fuel them and each pulsation matches the occurrence of the jets. By observing the X-ray spectrum with RXTE, researchers have discovered the interior of the disk creates enough radiation to halt the gas flow – an outward wind which negates the inward flow – and shuts down activity.  As a result, the inner disk glows hot and bright, eliminating itself as it flows toward the black hole and kick starts the jet activity again.  It’s a process that happens in as little as 40 seconds!

Right now astronomers aren’t able to prove that IGR J17091 has a particle jet, but the regular pulsations indicate it. Records show this “heartbeat” occurs about every five seconds – about 8 times faster than its counterpart and some 20 times more faint. Numbers like this would make it a very tiny black hole.

“Just as the heart rate of a mouse is faster than an elephant’s, the heartbeat signals from these black holes scale according to their masses,” said Diego Altamirano, an astrophysicist at the University of Amsterdam in The Netherlands and lead author of a paper describing the findings in the November 4 issue of The Astrophysical Journal Letters. It’s just the beginning of a full scale program involving RXTE to compare information from both black holes.  Even more detailed data will be added from NASA’s Swift satellite and XMM-Newton, too.

http://www.youtube.com/watch?feature=player_embedded&v=-s5GVZLcxzk 

“Until this study, GRS 1915 was essentially a one-off, and there’s only so much we can understand from a single example,” said Tod Strohmayer, the project scientist for RXTE at NASA’s Goddard Space Flight Center in Greenbelt, Md. “Now, with a second system exhibiting similar types of variability, we really can begin to test how well we understand what happens at the brink of a black hole.”

Original Story Source: NASA Mission News

Curiosity Starts First Science on Mars Sojurn – How Lethal is Space Radiation to Life’s Survival


NASA's Mars Science Laboratory Curiosity rover is currently cruising to Mars and is already investigating the lethality of the interplanetary space radiation environment to humans. After touchdown, Curiosity will investigate Mars' past or present ability to sustain microbial life. Credit: NASA/JPL-Caltech

Barely two weeks into the 8 month journey to the Red Planet, NASA’s Curiosity Mars Science Lab (MSL) rover was commanded to already begin collecting the first science of the mission by measuring the ever present radiation environment in space.

Engineers powered up the MSL Radiation Assessment Detector (RAD) that monitors high-energy atomic and subatomic particles from the sun, distant supernovas and other sources.

RAD is the only one of the car-sized Curiosity’s 10 science instrument that will operate both in space as well as on the Martian surface. It will provide key data that will enable a realistic assessment of the levels of lethal radiation that would confront any potential life forms on Mars as well as Astronauts voyaging between our solar systems planets.

“RAD is the first instrument on Curiosity to be turned on. It will operate throughout the long journey to Mars,” said Don Hassler, RAD’s principal investigator from the Southwest Research Institute in Boulder, Colo.

These initial radiation measurements are focused on illuminating possible health effects facing future human crews residing inside spaceships.


“We want to characterize the radiation environment inside the spacecraft because it’s different from the radiation environment measured in interplanetary space,” says Hassler.

RAD is located on the rover which is currently encapsulated within the protective aeroshell. Therefore the instrument is positioned inside the spacecraft, simulating what it would be like for an astronaut with some shielding from the external radiation, measuring energetic particles.

“The radiation hitting the spacecraft is modified by the spacecraft, it gets changed and produces secondary particles. Sometimes those secondary particles can be more damaging than the primary radiation itself.”

“What’s new is that RAD will measure the radiation inside the spacecraft, which will be very similar to the environment that a future astronaut might see on a future mission to Mars.”

Curiosity Mars Science Laboratory (MSL) Spacecraft During Cruise with Navigation Stars. Artist's concept of Curiosity during its cruise phase between launch on Nov. 26, 2011 and final approach to Mars in August 2012. Credit: NASA/JPL-Caltech

Curiosity’s purpose is to search for the ingredients of life and assess whether the rovers landing site at Gale Crater could be or has been favorable for microbial life.

The Martian surface is constantly bombarded by deadly radiation from space. Radiation can destroy the very organic molecules which Curiosity seeks.

“After Curiosity lands, we’ll be taking radiation measurements on the surface of another planet for the first time,” notes Hassler.

RAD was built by a collaboration of the Southwest Research Institute, together with Christian Albrechts University in Kiel, Germany with funding from NASA’s Human Exploration Directorate and Germany’s national aerospace research center, Deutsches Zentrum für Luft- und Raumfahrt.

“What Curiosity might find could be a game-changer about the origin and evolution of life on Earth and elsewhere in the universe,” said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington. “One thing is certain: The rover’s discoveries will provide critical data that will impact human and robotic planning and research for decades.”

Curiosity was launched from Florida on Nov. 26. After sailing on a 254 day and 352-million-mile (567-million-kilometer) interplanetary flight from the Earth to Mars, Curiosity will smash into the atmosphere at 13,000 MPH on August 6, 2012 and pioneer a nail biting and first-of-its-kind precision rocket powered descent system to touchdown inside layered terrain at Gale Crater astride a 3 mile (5 km) high mountain that may have preserved evidence of ancient or extant Martian life.

Miraculously, NASA’s Opportunity Mars rover and onboard instruments and cameras have managed to survive nearly 8 years of brutally harsh Martian radiation and arctic winters.

Curiosity MSL science instruments are state-of-the-art tools for acquiring information about the geology, atmosphere, environmental conditions, and potential biosignatures on Mars. Credit: NASA

Incoming! Meteorite Shockwaves Could Set Off Martian Dust Avalanches                                          


Artist's conception of an asteroid impact on Mars. (Image painted by William K. Hartmann, co-founder of the Planetary Science Institute, Tucson, Ariz.)

They are headed toward the surface like a speeding freight train… and running ahead of them is a shockwave. Just like a loud sound can trigger a snow avalanche here on Earth, the shockwave of a meteorite crashing through the Martian atmosphere could trigger dust avalanches on the surface before an actual impact.

According to a study led by University of Arizona undergraduate student, Kaylan Burleigh, there is sufficient photographic evidence to prove that incoming meteorites are producing enough energy to impact the surface environment just a much as the strike. Mars’ thin atmosphere also contributes, since the lesser density means most meteorites survive the trip to the surface. “We expected that some of the streaks of dust that we see on slopes are caused by seismic shaking during impact,” said Burleigh. “We were surprised to find that it rather looks like shockwaves in the air trigger the avalanches even before the impact.”

HiRISE image of the study area showing the central crater with two dagger-like features extending at an angle (red and blue arrows). Called scimitars, these features most likely resulted from shockwave interference just before impact. (Image: NASA/JPL-Caltech/The University of Arizona)

Spotting new craters happens frequently. Thanks to the HiRISE camera on board NASA’s Mars Reconnaissance Orbiter, researchers find up to twenty newly formed craters that measure between 1 and 50 meters (3 to 165 feet) each year. To perform their study, the team focused their attention on a grouping of five craters which formed at the same time. This quintuplet is located near the Martian equator, about 825 kilometers (512 miles) south of the boundary scarp of Olympus Mons. Earlier investigations of the area had revealed dark streaks which were surmised at the time to be landslides, but no one thought to credit them to an impact theory. The largest crater in the cluster measures 22 meters, or 72 feet across and the multiple formation is thought to have occurred due to a shattering of the meteor just ahead of final impact.

“The dark streaks represent the material exposed by the avalanches, as induced by the the airblast from the impact,” Burleigh said. “I counted more than 100,000 avalanches and, after repeated counts and deleting duplicates, arrived at 64,948.”

As Burleigh took a closer look at the distribution of avalanches around the impact site, he noticed a lot of relative things, but the most important was a curved formation described as scimitars. This was a major clue as to how they were formed. “Those scimitars tipped us off that something other than seismic shaking must be causing the dust avalanches,” Burleigh said.

Just as a freight train sends a rumble before it arrives, so does the incoming meteor. By using computer modeling, the team was able to simulate how a shockwave could form and match the scimatar patterns to the HiRISE images. “We think the interference among different pressure waves lifts up the dust and sets avalanches in motion. These interference regions, and the avalanches, occur in a reproducible pattern,” Burleigh said. “We checked other impact sites and realized that when we see avalanches, we usually see two scimitars, not just one, and they both tend to be at a certain angle to each other. This pattern would be difficult to explain by seismic shaking.”

Because there are no plate tectonics, nor water erosion issues, these types of findings are very important to understanding how many Martian surface features are formed. “This is one part of a larger story about current surface activity on Mars, which we are realizing is very different than previously believed,” said Alfred McEwen, principal investigator of the HiRISE project and one of the co-authors of the study. “We must understand how Mars works today before we can correctly interpret what may have happened when the climate was different, and before we can draw comparisons to Earth.”

Original Story Source: University of Arizona News.

Meet the snow pilots


Are bacteria manipulating the weather?

Snow can be a powerful thing. It can bring a nation’s transport sys¬tem to its knees and bring out the inner child from within the most dour and life-weary soul. It is a virgin canvas wait¬ing for the imprint of an angel. It is a fluffy mound, pregnant with sculptural potential and is a fort – complete with artillery.

Most of us have seen at least a dusting of snow in the last couple of days but what caused it to fall in the first place?

You might think that snow is just what happens to rain when it gets a bit chilly but things are a lot more complicated than that.
For a start, it hasn’t been cold enough for ice to form spontaneously.

We all know that water freezes at 0C but you might not know that at temperatures above -40C or so, it actually needs a kick-start to get those ice crystals forming.

This kick-start comes in the form of nucleators – tiny particles that act as a core around which water molecules can cluster and form crystals.Any small particle, such as dust or soot, works well but there is one nucleator that rules them all – bacteria. Some bacteria produce a special protein that is custom-built to encourage ice to form. The protein’s surface structure mimics that of an ice crystal, which encourages nearby water molecules to adopt the same structure. With the water molecules already arranged in an ice-like lattice, it is much easier for ice crystals to form – allowing water to freeze at relatively high temperatures.

One such bacterium is Pseudomonas syringae, which uses its ice-forming protein to create ice crystals in the plant cells it infects. The crystals cause its host’s cells to burst, allowing the bacterium easy access to its nutrients. In fact, P. syringae’s ice-forming talents are responsible for much of the frost damage that can wreck plants in the early spring.

But what have bacteria got to do with snow? In 2009, Louisiana State University looked at snow from all over the planet. They found that at the heart of almost every snowflake were cells containing microbial DNA. It seems that without bacteria there is no snow.

[Graphic: How bacteria might control the weather. Click to make bigger]

But what could bacteria be gaining from making it snow and what are they doing up in the clouds at all?

One theory is that they are using the clouds as a sort of giant conveyor belt that allows them to populate new areas. In fact, studies of clouds have shown that, on average, they carry with them tens of thousands of living cells in every millilitre of water.

But bacteria’s role in the planet’s weather mechanisms might be even more complex than just making it snow. Some studies suggest that they might actually be making clouds form in the first place. Many microbes, including bacteria, produce a chemical called dimethyl sulphide as a metabolic by-product, which acts as a nucleator for the formation of water droplets. In fact, dimethyl sulphide produced by phytoplankton in the oceans has been linked with cloud formation for some time.

But are bacteria ‘deliberately’ creating clouds to ferry themselves around the planet and then making it snow so they can get back to earth?
We don’t know. After all, it could be a coincidence that a biological by-product can form clouds and that an ice-forming protein that evolved to assist a bacterium to invade its plant host also makes it snow.

But what if it isn’t coincidence? What if these talents evolved to help bacteria spread around the planet to infect new hosts (like just malaria parasites use mosquitos)? Just imagine, one of Earth’s smallest life forms may have been manipulating an entire planet’s hydrological cycle all along.

Makes you think a little differently about all that snow, doesn’t it..?

Taking a bite from Earth's Core



A scientist sits at the helm of a revolutionary new drilling machine of his own design, called the Iron Mole. At the pull of a lever, the machine lurches forward and, in a wake of flying soil and rock, vanishes underground. 

The scientist and his plucky assistant find themselves in a strange subterranean cavern – a labyrinthine world populated by prehistoric beasts and primitive Palaeolithic peoples. So begins their great adventure at the ‘centre of the Earth’… or at least as Jules Verne imagined it.

Back in the real world, no Iron Mole or any amount of derring-do would enable a scientist to travel anywhere close to heart of our planet. In fact, the deepest we’ve ever managed to drill is a paltry 15km (nine miles) and that’s only 0.5 per cent of the 3,000km (1,900-mile) distance to the core.

[Graphic: How the Earth got its core... what's inside Earth...and how we know what's there at all. ]

As such, everything we do know about our planet’s iron heart has been inferred by studying seismic data and the Earth’s magnetic field.
Scientists are now taking things into their own hands, but rather than fashioning Earth-crunching behemoths, they instead plan to recreate the planet’s core in the laboratory. At the European Synchrotron Radiation Facility (ESRF) a new experiment has just gone on line that will do just that.

The ESRF is a particle accelerator capable of producing intense beams of X-rays that will be used to probe iron and other materials in incredible detail as they are subjected to the same temperatures and pressures present in the centre of the Earth.

At the heart of the experiment is a device called a diamond anvil cell. It might sound like the name of an unsuccessful 70s prog rock band, but it is actually a remarkably elegant way to create very high pressures. It takes advantage of diamond’s unique strength to crush tiny samples between two finely crafted points.

High-power lasers are then fired at the sample, heating them to more than 10,000C. With core-like conditions applied, a beam of X-rays is used to probe the exact chemistry and composition of the samples.


[Graphic: How scientists recreate the Earth's core using diamonds and lasers. ]

As well as giving an insight into the make-up of the Earth’s solid inner core, the experiment will also shed light on the dynamic mechanisms that help drive our planet’s magnetic field.

Space junk: A problem that must be addressed


[Phobos Grunt, Russia's Mars probe, is currently floundering in Earth's orbit and is at risk of breaking up in our atmosphere. But the imperiled craft is far from alone up there]

Once upon a time the heavens were pristine and perfect. Humanity, with its propensity to surround itself with life's detritus, was firmly tethered to the ground, so it looked like the space on Earth's doorstep would remain forever untainted. Then, someone had the bright idea that mankind could shake free of his Earthly shackles and the age of space junk was born.

Since then, humanity has been given the opportunity to build a heavenly extension to his Earthly landfill site and now, – just fifty years since he dropped his first orbital crisp packet – the space around Earth has become a bit of a junkyard.

In fact since the launch of Sputnik in 1957, mankind has lofted more than 6,500 satellites into god’s backyard. Add to that some spent rocket stages and other bits and bobs travelling at more than 28,000 kilometres per hour and (one or two collisions later) you have swarm of space debris more numerous than the locust visited upon Ancient Egypt (and far more dangerous).

[Image above: A model of all the space junk in Earth orbit large enough to be tracked. ESA]

Just a few months ago the inhabitants of the International Space Station were forced to evacuate to their Soyuz lifeboat as a swarm of potentially ISS-disabling debris honed into view. More recently, in October, a German satellite, Rosat, plunged to Earth and scattered debris across the Bay of Bengal and, in September, a NASA upper atmosphere research satellite (UARS) shuffled off its mortal coil and crashed into the Pacific Ocean.


[Graphic: How much space junk is there and how dangerous is it? – Click to blow up]

But space debris is more than just a passing danger to equipment – even a tiny flake of paint becomes a potentially deadly projectile when travelling at orbital speeds. The risk to the Space Station and the astronauts that occupy it taken very seriously by Nasa – in fact it has been estimated that in the lifetime of the Station there is a one in 12 chance that an astronaut will be killed by space debris. This wasn’t the first time the Space Station has been threatened by hordes of marauding space junk and, since 1999, it has had to change its orbit about a dozen times to step out of the way.

The risk to commercial satellites is also well documented and, with several high-profile loses in the last two years alone, space junk is problem that is going to have to addressed sooner or later.

In September, the National Research Council published a 180-page report on NASA’s efforts to reduce the risk posed by space debris. They recommended that orbital debris programmes should be given greater investmnet and that NASA (and other space agencies) must sharpen up their long-term debris modeling systems and improve their ability to measure and track space junk. There are some international guidelines in place that concern the reduction of space debris, but they don't address into whose lap the responsibilty for cleaning it all up will fall.

After all, if we have this much junk littering our doorstep so soon after the dawn of the space age, what’s Earth going to look like by the time Star Trek becomes a reality?


 

 

A long history of failed Mars missions


Mars has long occupied a special place in humanity’s consciousness and imagination. For millennia, it has been associated with malevolence, pestilence and disaster. Ancient cultures saw the Red Planet as the physical incarnation of various capricious and violent gods – an incarnation that demanded worship and sacrifice. For the Egyptians, it was ominously known as The Red One, for the Babylonians, it was The Star of Death and for Romans it was The God of War (Mars).

Even into the 20th century, Mars was a planet that loomed large as an object of fear. We imagined a world inhabited by a violent alien culture – little green men hell-bent on destroying humanity and claiming Earth for their own.

Then came the space age and the opportunity to visit Mars in the flesh. But, even as grainy images of a lifeless and benign world finally quenched the flames of age-old fears, a new myth, no less malevolent, was rising phoenix-like from the ashes of the old. Mars was to gain a new reputation as a technology devouring terror – a ‘Great Galactic Ghoul’ every bit as capricious as its ancient mythological forebears. In the history of Mars exploration, 37 missions have attempted to reach the Red Planet and, for one reason or another, about two-thirds of those missions ended in failure.


[It looks as if Russia's latest Mars mission, Phobos Grunt, will be the latest victim of the Galactic Ghoul]

In 1961 and 1962, five missions tried and failed to reach Mars – four didn’t even manage to escape Earth’s gravity. In 1964, Nasa’s Mariner 3 failed to deploy its solar panels and its batteries went flat. The following year, Russia lost contact with its Zond 2 probe and it floated lifelessly past its objective and, in 1971, another Russian mission (this time a lander) made history for making Mars’ first man-made crater.

More recently, in 1993, Nasa’s Mars Observer went Awol after a leaking fuel tank caused the craft to spin out of control. In 1999, Nasa’s Mars Climate Orbiter burned up in the Martian atmosphere because one of the project’s contractors, Lockheed Martin, had used imperial instead of metric units to program the craft’s approach.

[Nasa's Mars Science Laboratory, Curiosity, launched safely on Saturday. But it's a long road to Mars]

In recent weeks, the Galactic Ghoul has been tempted by some tasty new treats. On November 9, Russia launched Phobos Grunt (meaning Phobos Soil) – an ambitious mission to take samples from the Martian moon, Phobos, and return them to Earth. But within hours of its launch it fell into the grip of the Ghoul and stopped communicating with its mission controllers. Despite some recent success by the European Space Agency in reopening communications with the craft, it seems that Russia’s latest attempt to break the ‘curse of Mars’ will end like so many others before it – in Earth’s atmosphere as a ball of fire.

Nasa was up next and, on Saturday, its latest Mars rover was lofted safely into space. The Mars Science Laboratory, or Curiosity as it is known, one of the largest and is certainly the most ambitious craft ever to attempt to land on an alien world. Perhaps the Ghoul’s appetite has been satiated for now but it’s a long seven-month journey to the Red Planet and, even if it makes it to the beast’s doorstep, the machine will still have to contend with the so-called ‘six-minutes of terror’ as it attempts to land its car-sized bulk safely on a planet that has a poor record for welcoming visitors.

 

The (wholly) Earth catalogue



[Above: According to Nasa, Kepler-22b, has both land and water and has an average surface temperature of around 22C (72F) – perfect for life.
The Planetary Habitability Laboratory, who compiled the catalogue, are a little more conservative and cautious in their assessment of Kepler-22b and are awaiting further data before ranking the planet as a potentially habitable world]

Last week, the world got very excited about the discovery of a ‘new Earth’ – an alien world that seems to orbit its parent star at just the right distance to make the possibility of life existing there, well, a possibility.

The planet in question, Kepler-22b, was discovered by Nasa’s exoplanet-hunter – the Kepler Space telescope – and is perfect for life, according to the agency.
But sometimes Nasa can be a bit like an excitable puppy and, sometimes, when it claims to have caught a rabbit, it just turns out to be a squeaky chew-toy.

Many scientists are being rather more sober in their assessments of Kepler-22b – pointing out that, althoughwe know where it is and how big it is, we do not yet know what it is made of (see finding out its mass, opposite), which has a massive bearing (no pun intended) on whether or not the planet can support life.

But that doesn’t mean we can’t be excited about the prospect of finding another world just like
Earth, after all, there are potentially a lot of them out there (Kepler alone has identified 2,326 exoplanets).

Now a website has been launched which catalogues all the exoplanets discovered to date and even ranks them – comparing surface temperature, similarity to Earth and their ability to support life in its most basic forms.
So how does Kepler-22b rank?

Well, according to the Habitable Exoplanet Catalogue, it doesn’t even make the top 16...

You can explore the full list at the Planetary Habitability Lab's website here


 

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