Spectacular Type la supernova's mysteries revealed

Galaxy M82 in which the supernova exploded. 

Credit: NASA, ESA, & Hubble Heritage

New research by a team of UK and European-based astronomers is helping to solve the mystery of what caused a spectacular supernova in a galaxy 11 million light years away, seen earlier this year.

The supernova, a giant explosion of a star and the closest one to the Earth in decades, was discovered earlier this year by chance at the University of London Observatory.

These phenomena are extremely important to study because they provide key information about our universe, including how it is expanding and how galaxies evolve.

The new research into its cause, published in the latest issue of the Astrophysical Journal, used vast networks of radio telescopes in the UK and across Europe including the seven telescopes of e-MERLIN operated from The University of Manchester's Jodrell Bank Observatory.

These enabled them to obtain extremely deep images revealing a lack of radio emission from the supernova.

Known as 2014J, this was a Type la supernova caused by the explosion of a white dwarf star, the inner core of star once it has run out of nuclear fuel and ejected its outer layers.

A white dwarf star can explode if its mass increases to about 1.4x times that of the Sun. At this point its core temperature reaches the point where carbon starts to undergo nuclear fusion.

This spreads rapidly through the star resulting in a catastrophic thermonuclear explosion which rips the star apart, causing it to appear like a brilliant 'new star' shining billions of times brighter than the Sun.

For decades there has been a dispute about how this happens but these new results rule out the vast majority of models and show the merger of two white dwarf stars is by far the most likely cause.

The research was led by Miguel Pérez-Torres, researcher of the Spanish National Research Council who explained: "Supernovae play a fundamental role in the chemistry of galaxies and their evolution, as they are responsible for ejecting most of the heavy elements we see around us, including elements that cannot be formed in the interior of normal stars."

"A Nobel Prize was awarded in 2011 for the use of Type Ia supernovae to discover that the expansion of the Universe is accelerating. Yet, the basic question of what causes a Type Ia supernova was still a mystery".

Rob Beswick, a co-author of the research paper from the University of Manchester's Jodrell Bank Centre for Astrophysics added: "The explosion of a Type Ia supernova is a rare event in the nearby Universe."

"Supernova 2014J is the closest Type Ia supernova to Earth since 1986, and it's likely that more than a hundred years will pass until we see another such supernova so close to us."

"This was an amazing opportunity to learn more about these extremely important astrophysical phenomena and their underlying cause."

More information: "Constraints on the progenitor system and the environs of SN 2014J from deep radio observations" By M. A. Perez-Torres, P. Lundqvist, R. J. Beswick, C. I. Bjornsson, T. W. B. Muxlow, Z. Paragi, S. Ryder, A. Alberdi, C. Fransson, J. M. Marcaide, I. Marti-Vidal, E. Ros, M. K. Argo, J. C. Guirado are published in The Astrophysical Journal. iopscience.iop.org/0004-637X/792/1

Volcanic Plume Over Southern Atlantic Ocean Revealed Through False-Colour Imagery

Image Credit: Jeff Schmaltz /MODIS Land Rapid Response Team, NASA GSFC

The South Sandwich Islands, in the far southern Atlantic Ocean, are often shrouded with thick cloud, making it difficult to view the region from space.

Sometimes, however, the use of false-colour imagery can be used to reveal events that would otherwise be obscured under cloud cover.

The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite flew over the South Sandwich Islands on April 19, 2014 and acquired this false-colour image of the cloudy scene.

This false-colour image uses a combination of non-visible (middle infrared and infrared) and visible (red) light captured in bands 7, 2, and 1, respectively, to distinguish clouds from snow and ice.

Here the ice-covered islands appear bright turquoise, the clouds light turquoise and the water in the ocean appears deep black.

Because the volcanic plume is a moist mixture of gas and ash, it reflects all three forms of light relatively well, so it appears nearly white.

In the north of this image, a thin plume of white rises from the volcano on Zavodovski island, the northernmost of the South Sandwich Islands and streams to the northeast.

Further south, a wider white plume can be seen blowing across the Atlantic Ocean.

This plume rises from the Mount Michael volcano, which is a young and frequently active stratovolcano located on Saunders Island, near the center of the South Sandwich Island chain.

The white plume from Mount Michael forms a chain of swirling eddies as it blows to the northeast.

To the south, similar eddies can be seen behind three other islands. These are known as Von Kármán vortices.

These vortices can form nearly anywhere that fluid flow is disturbed by an object. Because the atmosphere behaves like a fluid, when streaming air hits a blunt object, such as a mountain peak, the wind is forced around the object.

The disturbance in the flow of the wind propagates downstream in a double row of vortices that alternate their direction of rotation, much like the eddies seen behind a pier in a river as water rushes past.

ESA Mars Express orbiter reveals overflowing craters

Credit: ESA/DLR/FU Berlin (G. Neukum)

Large and small, hundreds of thousands of craters scar the surface of Mars, hollowed out by a multitude of asteroids and comets that impacted the Red Planet throughout its history.

This image shows a region of the planet's northern hemisphere known as Hephaestus Fossae – after the Greek god of fire – that was imaged by the high-resolution stereo camera on ESA's Mars Express orbiter on 28 December 2007.

The image has been coloured to indicate the elevation of the terrain: green and yellow shades represent shallow ground, while blue and purple stand for deep depressions, down to about 4 km.

Scattered across the scene are a few dozen impact craters that cover a wide range of sizes, with the largest boasting a diameter of around 20 km.

The long and intricate canyon-like features that resemble riverbeds are the phenomenal aftermath of the same fierce impacts that created the largest craters.

When a small body such as a comet or an asteroid crashes at high speed into another object in the Solar System, the collision dramatically heats up the surface at the impact site.

In the case of the large crater seen in this image, the heat produced by such a powerful smash melted the soil – a mixture of rock, dust and also, hidden deep down, water ice – resulting in a massive overflow that flooded the surrounding environment.

Before drying up, this muddy fluid carved a complex pattern of channels while making its way across the planet's surface.

The melted rock–ice mixture also gave rise to the fluidised appearance of the debris blankets surrounding the largest crater.

Based on the lack of similar structures near the small craters in this image, scientists believe that only the most powerful impacts – those responsible for forging the largest craters – were able to dig deep enough to release part of the frozen reservoir of water lying beneath the surface.

NASA Chandra RX J1532.9+3021: Extreme power of black hole revealed

Credit: X-ray: NASA/CXC/Stanford/J.Hlavacek-Larrondo et al, Optical: NASA/ESA/STScI/M.Postman & CLASH team

Astronomers have used NASA's Chandra X-ray Observatory and a suite of other telescopes to reveal one of the most powerful black holes known.

The black hole has created enormous structures in the hot gas surrounding it and prevented trillions of stars from forming.

The black hole is in a galaxy cluster named RX J1532.9+3021 (RX J1532 for short), located about 3.9 billion light-years from Earth.

The image here is a composite of X-ray data from Chandra revealing hot gas in the cluster in purple and optical data from the Hubble Space Telescope showing galaxies in yellow.

The cluster is very bright in X-rays implying that it is extremely massive, with a mass about a quadrillion—a thousand trillion—times that of the Sun.

At the center of the cluster is a large elliptical galaxy containing the supermassive black hole.

The large amount of hot gas near the center of the cluster presents a puzzle. Hot gas glowing with X-rays should cool, and the dense gas in the center of the cluster should cool the fastest.

The Phoenix Cluster

The pressure in this cool central gas is then expected to drop, causing gas further out to sink in towards the galaxy, forming trillions of stars along the way.

However, astronomers have found no such evidence for this burst of stars forming at the center of this cluster.

This problem has been noted in many galaxy clusters but RX J1532 is an extreme case, where the cooling of gas should be especially dramatic because of the high density of gas near the center.

Out of the thousands of clusters known to date, less than a dozen are as extreme as RX J1532. The Phoenix Cluster is the most extreme, where, conversely, large numbers of stars have been observed to be forming.

What is stopping large numbers of stars from forming in RX J1532? 
Images from the Chandra X-ray Observatory and the NSF's Karl G. Jansky Very Large Array (VLA) have provided an answer to this question.

The X-ray image shows two large cavities in the hot gas on either side of the central galaxy (mouse over the image for a labeled version).

The Chandra image has been specially processed to emphasize the cavities. Both cavities are aligned with jets seen in radio images from the VLA.

The location of the supermassive black hole between the cavities is strong evidence that the supersonic jets generated by the black hole have drilled into the hot gas and pushed it aside, forming the cavities.

More information: A paper describing this work was published in the 10 November 2013 issue of The Astrophysical Journal and is available online: dx.doi.org/10.1088/0004-637X/777/2/163 . Preprint: arxiv.org/abs/1306.0907

Hawaii Night Sky Revealed in Stunning New Video - Sean Goebel

A new viral time-lapse video depicts the Milky Way over Mauna Kea, Hawaii, in amazing detail, complete with telescopes and dancing laser beams.

Sean Goebel, a graduate student in astronomy at the University of Hawaii at Manoa, created the new Hawaii night sky video from photographs shot on three consecutive nights in April and four nights in the summer of 2013.

Time-Lapse Video Still of Observatories Atop Mauna Kea, Hawaii Credit: Sean Goebel

The film features the night sky progression over Mauna Kea, a 13,803-foot (4,207 meters) mountain on Hawaii's Big Island, and its many telescopes.

The Keck, Gemini and Subaru telescopes each have lasers, which are used to remove the blurring effects of Earth's atmosphere using adaptive optics.

Goebel set up his cameras on nights when the weather was clear, the moon was small and when he knew the telescopes would be running the lasers.

On some of the nights, astronomers were using the lasers to observe the black hole at the center of the Milky Way.

Filming a typical scene took about five hours, using two digital SLR cameras (a Canon 5D Mk. II and Rebel XT) taking 300 1-minute exposures.

Goebel used a home-built rotary table to create motion in the scenes. He later edited the images into a video.

ESA's Mars Express: Huge Martian Landforms Detail Revealed

ESA's Mars Express orbited the Red Planet nearly 12,500 times by October 2013. Its high resolution stereo camera images, assembled in this "fly-around," show riverbeds, volcanoes, canyons and craters.

Credit: ESA / DLR / FU Berlin (G. Neukum)

Hubble Video: 'Space slinky' revealed in 13-year time-lapse

A "space slinky" has been imaged in action for the first time: a series of pictures shot by the Hubble Space Telescope over 13 years has been pieced together to reveal the spiral motion of a jet of superheated gas shooting from the central black hole of the nearby M87 galaxy (see video, above).

When a supermassive black hole at the centre of a large galaxy is actively feeding, it can fire jets of plasma into space at high speed.

Previous images of such jets, captured in another part of the universe, also provided evidence for a corkscrew shape.

This was probably created as the plasma travelled along coiled magnetic field lines emanating from the swirling disc of material falling into the black hole but those images had a hard time determining if the material was spiralling up the length of the field lines or simply moving from side to side.

Eileen Meyer

Using images from Hubble, Eileen Meyer from the Space Telescope Science Institute (STCI) in Baltimore, Maryland and colleagues analysed a jet spurting out of M87's central black hole.

Their detailed view of the jet in motion shows that it is made up of clumps of gas that brighten and fade over time.

The blobs have complex dynamics, with gas speeding up at different rates along the jet and even stationary spots in some of the far-out clumps.

The work should give insight into how galaxies evolve, since high-speed jets produced during a black hole's active phase are thought to play a significant role.

"By studying the details of this process, we hope to learn more about galaxy formation and black hole physics in general," says Meyer.

The team's next step will be to study three more jets using Hubble observations, to see if they behave in similar ways.

Journal reference: The Astrophysical Journal Letters, DOI: 10.1088/2041-8205/774/2/L21

Antarctic and Arctic sea-ice revealed in 1964 satellite maps

The NSIDC project examined almost 40,000 images from the Nimbus-1 archive to produce the September 1964 maps of Arctic (L) and Antarctic (R) sea-ice extent.

The earliest satellite maps of Arctic and Antarctic sea-ice have been assembled by scientists.

They were made using data from Nasa's Nimbus-1 spacecraft, which was launched in 1964 to test new technologies for imaging weather systems from orbit.

The satellite's old pictures have now been re-analysed to determine the extent of the marine ice at the poles in the September of that year.

Regular Earth Observation mapping from space did not begin until 1978.

One key finding is that marine floes around the White Continent in the 1960s were probably just as extensive as they are today.

The new snapshot, published in The Cryosphere journal, therefore helps put current ice conditions into a longer-term context, say researchers at the US National Snow and Ice Data Centre (NSIDC).

It is also just a fascinating story of how old scientific data can be given a new lease of life.

Matching up
The Nimbus-1 satellite was a short-lived mission that observed the Earth's clouds in black and white video, which it transmitted to the ground as an analogue TV signal.

Those transmissions were then photographed on to 35mm film and archived. The NSIDC team had to pull the canisters containing the original film out of storage to perform the re-analysis.

NSIDC
"The canisters were kind of forgotten, almost lost in time, until about four years ago when they were found and it was realised they might contain some useful, interesting data," explained the NSIDC's Dr Walt Meier.

"We then got some funding to digitise the data and analyse it. I was sceptical at first; the quality of the data is nothing like what we can get now.

Dr Walt Meier

"But it turned out to be really good, especially in the Antarctic, where it was surprisingly easy to determine the ice edge. Don't get me wrong, it was certainly a challenge," he told reporters.

"One of the things you have to do is geo-locate the data - you have to know where you are looking. There was some information in there to help us, but we had to take care in matching up the images and locating them on the Earth as accurately as we could."

Although the satellite worked for just three weeks, it covered a period of key interest to polar scientists.

Read more of this article here

Sun's Magnetic 'Heartbeat' Revealed

A simulation of magnetic fields at the time of solar maximum.

CREDIT: University of Montreal Solar Physics Research Group

A magnetic "solar heartbeat" beats deep in the sun's interior, generating energy that leads to solar flares and sunspots, according to new research.

A new supercomputer simulation, described in the April 4 edition of the journal Science, probes the sun's periodic magnetic field reversals.

Every 40 years, according to the model, the sun's zonal magnetic field bands switch their orientation, or polarity.

That cycle is about four times longer than the 11-year sunspot cycle that governs the level of solar activity. Being able to model such a regular, long-term process is remarkable, the scientists said.

The new research, led by the University of Montreal's Paul Charbonneau, describes work from both his research group and other, independent coalitions simulating the sun's interior.

Temperature variability on a model intended to approximate what goes on inside the sun.

CREDIT: University of Montreal Solar Physics Research Group

Dissipating turbulence
Modeling the sun has been a sticky problem for decades.

The first attempts in the 1980s captured only a rough approximation of the turbulence inside of the sun.

Turbulence, when it occurs, happens at both large and small scales.

The large scales are easy to simulate, but in the sun, a small feature only about tens of miles across is just as important in understanding how fluid propagates.

When energy from turbulence dissipates, the turbulence flows into smaller and smaller whirlpool shapes, called vortices.

You can see this for yourself, Charbonneau said, when swirling your hand in a full bathtub. The movement will produce a vortex in the water that will gradually break up into tinier ones that dissipate the energy.

On the sun, dissipation takes place at a scale of tens of yards. That's extremely minute, compared with the size of the sun, which is 1 million times larger than Earth. "There's no way we can capture that in a simulation," Charbonneau stated.

To approximate this process, scientists typically limit the resolution to about 6.2 miles (10 kilometers). This, however, creates an energy buildup in the simulation that will "blow up" the model before it can run for very long, Charbonneau said.

Sprial galaxy: Hidden depths of Messier 77 revealed

The NASA/ESA Hubble Space Telescope has captured this vivid image of spiral galaxy Messier 77 -- a galaxy in the constellation of Cetus, some 45 million light-years away from us. 

The streaks of red and blue in the image highlight pockets of star formation along the pinwheeling arms, with dark dust lanes stretching across the galaxy's starry center. 

The galaxy belongs to a class of galaxies known as Seyfert galaxies, which have highly ionized gas surrounding an intensely active center. (Credit: NASA, ESA and A. van der Hoeven)

Messier 77 is a galaxy in the constellation of Cetus, some 45 million light-years away from us. Also known as NGC 1068, it is one of the most famous and well-studied galaxies. It is a real star among galaxies, with more papers written about it than many other galaxies put together.

Despite its current fame and striking swirling appearance, the galaxy has been a victim of mistaken identity a couple of times; when it was initially discovered in 1780, the distinction between gas clouds and galaxies was not known, causing finder Pierre Mechain to miss its true nature and label it as a nebula. It was misclassified again when it was subsequently listed in the Messier Catalogue as a star cluster.

Now, however, it is firmly categorised as a barred spiral galaxy, with loosely wound arms and a relatively small central bulge. It is the closest and brightest example of a particular class of galaxies known as Seyfert galaxies -- galaxies that are full of hot, highly ionised gas that glows brightly, emitting intense radiation.

Strong radiation like this is known to come from the heart of Messier 77 -- caused by a very active black hole that is around 15 million times the mass of our Sun.

 Material is dragged towards this black hole and circles around it, heating up and glowing strongly. This region of a galaxy alone, although comparatively small, can be tens of thousands of times brighter than a typical galaxy.

Although no competition for the intense centre, Messier 77's spiral arms are also very bright regions. Dotted along each arm are knotty red clumps -- a signal that new stars are forming.

These baby stars shine strongly, ionising nearby gas which then glows a deep red colour as seen in the image above.

The dust lanes stretching across this image appear as a rusty, brown-red colour due to a phenomenon known as reddening; the dust absorbs more blue light than red light, enhancing its apparent redness.

Ancient Mega-Flood on Mars Revealed in 3D

The Mars map shows the location of the nearly 1,000-kilometer Marte Vallis channel system on Mars created during an ancient mega-flood. 

Marte Vallis is filled with lava obscuring the source and morphology of the channels. Image released March 7, 2013.

CREDIT: NASA/MOLA Team/Smithsonian Institution

Radar scans of Mars have revealed the first 3D look at water-carved channels buried beneath the Red Planet's surface, researchers say.

The discovery shows that a major underground channel generated by an ancient mega-flood is twice as deep as thought, and sheds light on how water shaped the surface of Mars, scientists added.

Mars today is cold and dry, with most of its water locked in polar ice caps, and researchers think its surface has been largely barren for the past 2.5 billion years. However, channels crisscrossing its surface hint that waters once flooded the Red Planet's surface.

The largest of the channels engraved into Mars within the past 500 million years belong to the 600-mile-long (1,000 kilometer) Marte Vallis system. Probing Marte Vallis could offer hints on a time otherwise thought of as cold and dry.

However, Marte Vallis lies in Elysium Planitia, an expanse of plains along the Martian equator. This area is the youngest volcanic region on Mars, and massive volcanism throughout the past several hundred million years has covered most of its surface with lava, burying evidence of its recent history, including the source and most of the length of Marte Vallis.

Now, using the shallow radar onboard the Mars Reconnaissance Orbiter, scientists have scanned beneath the surface of Elysium Planitia. Their data helped generate a 3D reconstruction of Marte Vallis, revealing many details that lava flows buried long ago.

"This is the first time we've been able to see buried flood channels on a planet other than the Earth," lead study author Gareth Morgan, a geologist at the Smithsonian's National Air and Space Museum, reported.

The researchers found the channels of Marte Vallis were at least 230 feet (70 meters) deep, making them at least twice as deep as thought.

"That shows previous ideas of erosion, of how much water have gone through Marte Vallis, have been underestimated," Morgan said. "There was more significant flooding than before thought, and it's interesting to think of where this water might have come from during this relatively dry period."

This 3D visualization shows the buried Marte Vallis channels beneath the Martian surface created during an ancient mega-flood. 

Marte Vallis consists of multiple perched channels formed around streamlined islands. 

These channels feed a deeper and wider main channel. 

Note the surface has been elevated, and scaled by a factor of 1/100 for clarity, with colours representing the elevation of the buried channels. 

Image released March 7, 2013. 

CREDIT: Smithsonian Institution/NASA/JPL-Caltech/Sapienza University of Rome/MOLA Team/USGS


By mapping the buried channels, researchers discovered the ancient gigantic floods that probably created Marte Vallis apparently originated deep underground from a now-buried portion of fissures known as Cerberus Fossae.

"The source of the floodwaters suggests they originated from a deep groundwater reservoir and may have been released by local tectonic or volcanic activity," Morgan said.

Marte Vallis is similar to more ancient systems of channels on Mars. The gargantuan floods that generated these channels may also have briefly radically changed the Red Planet's climate just as giant floods of Arctic water have on Earth. Learning more about Martian floods could provide information on key parts of that world's history, researchers said.

"There's also evidence of channels buried by lava or other sorts of materials in other areas on Mars, and we'd like to apply the same sort of radar studies to those," Morgan said.

The scientists detailed their findings online today (March 7) in the journal Science.

TED 2013: SpaceTop 3D see-through computer revealed

A transparent computer that allows users to reach inside and touch digital content has been unveiled at the TED conference in Los Angeles.

TED fellow Jinha Lee has been working on the SpaceTop 3D desktop in collaboration with Microsoft.

Allowing people to interact with machines in the same way they do with solid objects could make computing much more intuitive, he reported.

He can see the system coming into general use within a decade.

The system consists of a transparent LED display with built-in cameras, which track the user's gestures and eye movements.

Human touch 
The design was inspired by what he sees as a human need to interact with things.

"Spatial memory, where the body intuitively remembers where things are, is a very human skill," he said.

Translating this to the digital world will enable people to use computers more easily as well as complete more complex tasks.

"If you are working on a document you can pick it up and flip through it like a book," he reported.

For more precise tasks, where hand gestures are not accurate, there is a touchpad. It will allow, for example architects to manipulate 3D models.

"The gap between what the designer thinks and what the computer can do is huge. If you can put your hands inside the computer and handle digital content you can express ideas more completely," he said.

Not everyone is convinced by the Minority Report-style future that will see us interact with machine via touch.

In an interview with The Awl website designer Christian Brown said: "Human hands and fingers are good at feeling texture and detail, and good at gripping things - neither of which touch interfaces take advantage of.

"The real future of interfaces will take advantage of our natural abilities to tell the difference between textures, to use our hands to do things without looking at them."

Magic ball 
Mr Lee, a graduate from the Massachusetts Institute of Technology, is currently serving his military obligation in South Korea at Samsung Electronics, where he is working on TV interfaces.

At TED, which stands for Technology, Education and Design, he also demonstrated other projects he is working on, including ZeroN, a floating ball, which can literally be placed in midair.

It utilises electromagnetism to stay afloat and when coupled with software can be used for a variety of applications.

Secrets of Supermassive Black Holes Revealed

These images, taken with the 2.1-meter telescope at Kitt Peak National Observatory in Arizona, show galaxy shapes that are either physically intertwined or distorted by the gravity of nearby neighbors.

These AGN were known prior to the Swift survey, but Swift has found dozens of new ones in more distant galaxies. Credit:

NASA/Swift/NOAO/Michael Koss and Richard Mushotzky (Univ. of Maryland)

Researchers had scratched their heads over why such high-energy displays occurred, until now. The findings announced today confirm past theories that suggested that violence from galactic mergers can fuel the growth of central black holes.

"We find that about 25 percent of black holes found by Swift are in the process of merging," said team member Michael Koss of the University of Maryland in College Park, during a NASA teleconference.

About 60 percent of such active galaxies will merge completely within the next billion years to create giant black holes.

Hard X-ray action

Swift used its Burst Alert Telescope (BAT) to detect any telltale signs of hard X-rays, which rank between gamma-rays and X-rays on the electromagnetic spectrum of light.

Such hard X-rays can pass through interstellar gas or dust which otherwise blocks ultraviolet, optical and soft-X-ray light. Infrared radiation can also pass through the material, but may represent emissions from a galaxy's star nurseries rather than the central black holes.

The hard X-ray survey allowed astronomers to feel confident that they had spotted the majority of AGN within Swift's survey range of about 650 million light-years away. (A light-year is the distance that light can travel in one year — about 6 trillion miles (10 trillion km).)

Koss and his colleagues then followed up by spending 20 nights peering at the AGN with a 2-meter telescope at Kitt Peak National Observatory near Tucson, Ariz.

"Many of these galaxies are very close to us, so we see the severe distortion of the galaxy shapes," Koss explained. "In addition, we see that the galaxies are very close to each other and therefore will merge and interact very strongly."

Like good neighbours do!

The Cosmos revealed, slowly

If you could see into the back rooms of cosmology labs in Europe, you would see the European Cosmologists are doing their happy dance.

The European Space Agency's Planck mission is busy surveying the cosmic microwave background, aka the "echo" of the big bang, and in 2013 will release a feast of data that promises to deliver profound new insights into the origin of the universe.

Surely a victory for science? Only, it seems, if cosmologists can resist the temptation to gorge themselves on all those goodies.

A trio of astronomers have warned that, unless we use the information sparingly, we risk squandering a once-in-eternity opportunity (see arxiv.org/abs/0909.2649). If the whole data set is released at once, as is planned, any new ideas that cosmologists come up with may have to remain untested because they will have no further data to test them with.

This is a problem unique to cosmology. In other sciences, additional information is always available: you can always reset and rerun an experiment, or go out into the field to collect more data. Because of our fixed location in the universe, however, cosmology doesn't have that luxury.

There is only a finite amount of information we can gather about the universe, and once we gather all there is to know about one aspect of it - in this case the temperature fluctuations in the cosmic microwave background - the well runs dry.

In 2005, astronomers discovered a mysterious alignment of hot and cold spots in the CMB, which they dubbed the "axis of evil". If the phenomenon is real, it has important implications for our understanding of the universe.

The Planck data will be used to test it. But imagine if cosmologists find another, similar, mystery buried in the data. What will they use to test that one?

The answer, according to Roberto Trotta of Imperial College London, is to be frugal with what you let the cosmologists see. Instead of giving out all the data at once, the supply should be rationed.

Drip-feeding will allow the development of new hypotheses which can be tested as more of the Planck information is released. If we don't adopt this approach, we risk wasting the finest cosmology data set we have ever had, and remaining forever in the dark.

Illegal toxic waste spotted from space - environment - New Scientist

Illegal toxic waste spotted from space - environment - New Scientist

MOVE over Erin Brockovich. Today's environmental detectives can use radar, helicopters and even satellite images to help them spot illegal toxic waste dumps and help catch those responsible.

Ironically, the tightening of restrictions on waste disposal and the enforcement of new recycling laws have made illegal dumping more likely, turning it into big business for the criminals involved.

The trouble is digging up suspect dumps to investigate their contents can release toxins into local water supplies. But with new remote-sensing techniques, such as ground-penetrating radar (GPR), you can find toxic trash without disturbing the soil. Instead, you bounce microwaves off buried materials and the strength of returning signals provides clues to what they are.

Alastair Ruffell, a forensic geologist at Queen's University, Belfast in the UK, has used GPR in 17 cases for the environment agencies of Scotland, the Republic of Ireland and Northern Ireland. Most are ongoing, however three have resulted in the culprits being jailed and fined.

Ruffell's latest research shows that geophysical techniques can be used to characterise the waste (Environmental Forensics, DOI: 10.1080/15275920903130230). GPR surveys suggested the presence of a highly conductive waste such as farmyard slurry in a peat bog in Northern Ireland, simply because the suspect pocket in the bog reflected no microwaves.

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NASA Mars Reconnaissance Orbiter - Meteorites expose water

NASA's Mars Reconnaissance Orbiter has revealed frozen water hiding just below the surface of mid-latitude Mars. The spacecraft's observations were obtained from orbit after meteorites excavated fresh craters on the Red Planet.

Scientists controlling instruments on the orbiter found bright ice exposed at five Martian sites with new craters that range in depth from approximately half a meter to 2.5 meters (1.5 feet to 8 feet). The craters did not exist in earlier images of the same sites. Some of the craters show a thin layer of bright ice atop darker underlying material. The bright patches darkened in the weeks following initial observations, as the freshly exposed ice vaporized into the thin Martian atmosphere. One of the new craters had a bright patch of material large enough for one of the orbiter's instruments to confirm it is water-ice.

The finds indicate water-ice occurs beneath Mars' surface halfway between the north pole and the equator, a lower latitude than expected in the Martian climate.

"This ice is a relic of a more humid climate from perhaps just several thousand years ago," said Shane Byrne of the University of Arizona, Tucson.

Byrne is a member of the team operating the orbiter's High Resolution Imaging Science Experiment, or HiRISE camera, which captured the unprecedented images. Byrne and 17 co-authors report the findings in the Sept. 25 edition of the journal Science.