NASA WISE Discovers Coldest Brown Dwarf Neighbour of the Sun

This artist's conception shows a newfound object named WISE J085510.83-071442.5, the coldest known brown dwarf. 

Credit: Penn State University/NASA/JPL-Caltech

A brown dwarf as cold as the North Pole has been discovered lurking remarkably close to our solar system, and it appears to be the coldest of its kind yet found, scientists say.

Using NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope, astronomers discovered the dim, "failed star" lurking just 7.2 light-years away, making it the fourth closest system to our sun.

"It's very exciting to discover a new neighbor of our solar system that is so close," Kevin Luhman, an astronomer at Pennsylvania State University's Center for Exoplanets and Habitable Worlds, said in a statement.

"And given its extreme temperature, it should tell us a lot about the atmospheres of planets, which often have similarly cold temperatures."

This diagram illustrates the locations of the star systems closest to the sun. 

Credit: Penn State University

Brown dwarfs are sometimes called failed stars because they have many of the elements of that make up stars, but they lack the huge mass needed to kick off nuclear fusion in their core.

As a result, these objects don't radiate starlight and they sometimes resemble planets.

Some are even cool enough to have atmospheres much like gas giants.

While brown dwarfs are hidden in images taken in the visible spectrum, infrared telescopes like WISE can pick up the meager glow of brown dwarfs.

Luhman and colleagues first spotted the object in WISE data. It appeared to be moving quite fast, hinting that it was close by.

The team then investigated the object using Spitzer and the Gemini South telescope on Cerro Pachon in Chile to measure its distance and temperature.

"It is remarkable that even after many decades of studying the sky, we still do not have a complete inventory of the sun's nearest neighbours," Michael Werner, the project scientist for Spitzer at NASA's Jet Propulsion Laboratory in Pasadena, Calif., said in a statement.

Dubbed WISE J085510.83-071442.5, our newfound neighbor is now the record-holder for the coldest brown dwarf, with a temperature between minus 54 and 9 degrees Fahrenheit (minus 48 to minus 13 degrees Celsius), Luhman and colleagues say.

The previous record holders were more tepid, chilling only to room temperature.

At 3 to 10 times the mass of Jupiter, the object also may be one of the least massive brown dwarfs ever found, the astronomers say.

Because it is so small, the scientists say it's possible that the body is actually a planet ejected from its star system, but brown dwarfs are known to be quite common cosmic objects.

The findings were described April 21 in The Astrophysical Journal.

NAU-led team discovers comet hiding in plain sight

Don Quixote's coma and tail (left) as seen in infrared light by NASA's Spitzer Space Telescope. After image processing (right), the tail is more apparent. 

Image courtesy NASA/JPL-Caltech/DLR/NAU

For 30 years, a large near-Earth asteroid wandered its lone, intrepid path, passing before the scrutinizing eyes of scientists while keeping something to itself: 3552 Don Quixote, whose journey stretches to the orbit of Jupiter, now appears to be a comet.

The discovery resulted from an ongoing project led by researchers at Northern Arizona University using the Spitzer Space Telescope.

Through a lot of focused attention and a little bit of luck, they found evidence of cometary activity that had evaded detection for three decades.

"Its orbit resembled that of a comet, so people assumed it was a comet that had gotten rid of all its ice deposits," said Michael Mommert, a post-doctoral researcher at NAU who was a Ph.D. student of professor Alan Harris at the German Aerospace Center (DLR) in Berlin at the time the work was carried out.

What Mommert and an international team of researchers discovered, though, was that Don Quixote was not actually a dead comet-one that had shed the carbon dioxide and water that give comets their spectacular tails.

Instead, the third-biggest near-Earth asteroid out there, skirting Earth with an erratic, extended orbit, is "sopping wet," said NAU associate professor David Trilling.

The implications have less to do with potential impact, which is extremely unlikely in this case, and more with "the origins of water on Earth," Trilling said.

Comets may be the source of at least some of it, and the amount on Don Quixote represents about 100 billion tons of water-roughly the same amount found in Lake Tahoe.

Mommert said it's surprising that Don Quixote hasn't been depleted of all of its water, especially since researchers assumed that it had done so thousands of years ago but finding evidence of CO2, and presumably water, wasn't easy.

During an observation of the object using Spitzer in August 2009, Mommert and Trilling found that it was far brighter than they expected. "The images were not as clean as we would like, so we set them aside," Trilling said.

Much later, though, Mommert prompted a closer look, and partners at the Harvard-Smithsonian Center for Astrophysics found something unusual when comparing infrared images of the object: something, that is, where an asteroid should have shown nothing.

The "extended emission," Mommert said, indicated that Don Quixote had a coma-a comet's visible atmosphere-and a faint tail.

Mommert said this discovery implies that carbon dioxide and water ice also might be present on other near-Earth objects.

This study confirmed Don Quixote's size and the low, comet-like reflectivity of its surface. Mommert is presenting the research team's findings this week at the European Planetary Space Conference in London.

NASA NuSTAR: Space Telescope Discovers 10 Monster Black Holes

This optical colour image of galaxies is seen overlaidwith X-ray data (magenta) from NASA's black hole-hunting NuSTAR space telescope. 

The arrow points to magenta blobs indicating giant, supermassive black holes discovered by the space telescope. 

Credit: NASA/JPL-Caltech`

A powerful NASA space telescope has found not one, but 10 monster black holes lurking in the hearts of distant galaxies — the first major finds for the X-ray space observatory, scientists say.

The discoveries, which scientists say occurred "serendipitously," were made as astronomers reviewed images from NASA's Nuclear Spectroscopic Telescope Array (NuSTAR), an X-ray space telescope designed specifically to hunt black holes.

"We were looking at known targets and spotted the black holes in the background of the images," David Alexander, a professor with Durham University's physics department, said in a statement.

Then the team confirmed what they saw with observations from NASA's Chandra X-ray Observatory and the European Space Agency's XMM-Newton satellite, which also can look at low-energy light.

The 10 black holes discovered are just the beginning of hundreds of expected finds, the scientists added. With every supermassive black hole catalogued, scientists are hoping to better understand the population.

Surrounded by galaxies
According to NASA, discovering the supermassive black holes were a key piece of a puzzle first uncovered in 1962. Astronomers found a glow of X-rays in the background of the universe, but didn't know where the glow came from.

Today, scientists know the glow (also called the cosmic X-ray background) comes from very distant supermassive black holes, some of which are as large as 17 billion times the mass of the sun. But how these black holes form is still under investigation.

"Our early results show that the more distant supermassive black holes are encased in bigger galaxies," stated Daniel Stern, a co-author of the study and the project scientist for NuSTAR at NASA's Jet Propulsion Laboratory. "This is to be expected. Back when the universe was younger, there was a lot more action with bigger galaxies colliding, merging and growing."

While NuSTAR can detect these big black holes, other measurements (such as mass) come from agency observatories including the Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope.

The research appeared Aug. 20 in the Astrophysical Journal.

Spitzer discovers young stars with a 'hula hoop'

In this artist's impression, a disk of dusty material leftover from star formation girds two young stars like a hula hoop. 

As the two stars whirl around each other, they periodically peek out from the disk, making the system appear to "blink" every 93 days. 

Image credit: NASA/JPL-Caltech

Astronomers using NASA's Spitzer Space Telescope have spotted a young stellar system that "blinks" every 93 days.

Called YLW 16A, the system likely consists of three developing stars, two of which are surrounded by a disk of material left over from the star-formation process.

As the two inner stars whirl around each other, they periodically peek out from the disk that girds them like a hula hoop.

The hoop itself appears to be misaligned from the central star pair, probably due to the disrupting gravitational presence of the third star orbiting at the periphery of the system.

The whole system cycles through bright and faint phases, with the central stars playing a sort of cosmic peek-a-boo as the tilted disk twirls around them.

It is believed that this disk should go on to spawn planets and the other celestial bodies that make up a solar system.

Spitzer observed infrared light from YLW 16A, emitted by the warmed gas and dust in the disk that still swathes the young stars.

Other observations came from the ground-based 2MASS survey, as well as from the NACO instrument at the European Southern Observatory's Very Large Telescope in Chile.

NB: NACO is an Adaptive Optics facility producing images as sharp as if taken in space. It is also equipped with a spectrometer, polarimeter, coronographs, etc

YLW 16A is the fourth example of a star system known to blink in such a manner, and the second in the same star-forming region Rho Ophiuchus.

The finding suggests that these systems might be more common than once thought.

Blinking star systems with warped disks offer scientists a way to study how planets form in these environments.

The planets can orbit one or both of the stars in the binary star system. The famous science fictional planet Tatooine in "Star Wars" orbits two stars, hence its double sunsets.

Such worlds are referred to as circumbinary planets. Astronomers can record how light is absorbed by planet-forming disks during the bright and faint phases of blinking stellar systems, which in turn reveals information about the materials that comprise the disk.

"These blinking systems offer natural probes of the binary and circumbinary planet formation process," said Peter Plavchan, a scientist at the NASA Exoplanet Science Institute and Infrared Processing and Analysis Center at the California Institute of Technology, Pasadena, Calif., and lead author of a new paper accepted for publication in Astronomy & Astrophysics.

More information: arxiv.org/abs/1304.2398

ESA VLT Discovers Feeding galaxy caught in distant searchlight

This is an artist's impression of a galaxy accreting material from its surroundings. 

Credit: European Southern Observatory

An international group of astronomers that includes UC Santa Barbara astrophysicist Crystal Martin and former UCSB postdoctoral researcher Nicolas Bouché has spotted a distant galaxy hungrily snacking on nearby gas.

The gas is seen to fall inward toward the galaxy, creating a flow that both fuels star formation and drives the galaxy's rotation.

This is the best direct observational evidence so far supporting the theory that galaxies pull in and devour nearby material in order to grow and form stars. The results will appear in the July 5 issue of the journal Science.

Spiral galaxies like our own Milky Way formed billions of years ago in the dark matter concentrations that began to grow shortly after the Big Bang.

As gas cooled and condensed, stars formed, which, over time, synthesized heavy elements and polluted the galaxy with this enriched material upon their death.

But what that model has not been able to explain is the continuous formation of stars in some galaxies, despite the constant rate at which galaxies turn molecular gas into stars.

The simplest model calls for a closed system and predicts star formation should have ceased long ago due to the limited gas supply.

"It's been a problem," said Martin. Galaxies should use up their gas on a time scale that's much shorter than what has been observed, she explained.

In fact our own galaxy should have already run out of gas, but stars continue to form in it.

"Galaxies must have a mechanism for acquiring more gas," she continued, adding that, historically, no means has existed to directly detect the inflow of the cold fuel.

Now, however, thanks to the background light from the quasar HE 2243-60, Martin and her colleagues have been able to observe distinct signatures near a typical star-forming galaxy that indicate the inflow of gas feeding the galaxy.

In this scenario, gas is drawn into a galaxy and then circles around it, rotating with it before falling in.

Although some evidence of such accretion had been observed in galaxies before, the motion of the gas and its other properties had not been fully explored until now.

The background quasar is, by chance, perfectly well positioned for this study. "This kind of alignment is very rare, but was critical for this study," explained first author Bouché, who is now with the Research Institute in Astrophysics and Planetology in Toulouse, France.

The astronomers used two instruments known as SINFONI (Spectrograph for INtegral Field Observations in the Near Infrared) and UVES (Ultraviolet and Visual Echelle Spectrograph), both of which are mounted on European Southern Observatory's Very Large Telescope at the Paranal Observatory in northern Chile.

The new observations showed both how the galaxy itself was rotating and revealed the composition and motion of the gas outside the galaxy.

The result is the discovery of how an active star-forming galaxy feeds its prodigious growth, according to co-author Michael Murphy, from the Swinburne University of Technology in Australia.

"[We've] observed, as directly as possible, the feeding process for forming huge numbers of stars very quickly 11 billion years ago," he said.

The observation also strengthens the argument that low-mass galaxies are formed through these cold streams, which also allow galaxies to prolong their star formation process.

"It is impressive to see in the data the telltale signatures of this infalling gas matching those expected in numerical simulations," said Bouché.

More information: This research was presented in a paper entitled "Signatures of Cool Gas Fueling a Star-Forming Galaxy at Redshift 2.3", to appear in the 5 July 2013 issue of the journal Science.

NASA Chandra Discovers 26 another Black Holes in Andromeda Galaxy

26 new black hole candidates have been spotted in the neighboring Andromeda galaxy.

CREDIT: X-ray (NASA/CXC/SAO/R.Barnard, Z.Lee et al.), Optical (NOAO/AURA/NSF/REU Prog./B.Schoening, V.Harvey; Descubre Fndn./CAHA/OAUV/DSA/V.Peris)

Astronomers have discovered 26 new likely black holes in the neighbouring Andromeda galaxy — the largest haul of black hole candidates ever found in a galaxy apart from our own.

Black holes, which emit almost no light themselves, can be seen only by the light given off by material falling into them.

The supermassive black holes that populate the centers of most galaxies are easy to spot because their surroundings are so bright, but much smaller stellar mass black holes are considerably harder to find.

The 26 new candidates, in combination with nine previously discovered black holes in Andromeda, bring the known tally in that galaxy to 35.



"While we are excited to find so many black holes in Andromeda, we think it's just the tip of the iceberg," Robin Barnard, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., said in a statement. "Most black holes won't have close companions and will be invisible to us."

Robin Barnard

Most of the newfound black holes have about five to 10 times the mass of our sun, and resulted from the deaths of giant stars.

Seven of the new candidates were found within 1,000 light-years of the center of the Andromeda galaxy — more than the number of black holes near the core of our own Milky Way.

"We are particularly excited to see so many black hole candidates this close to the center, because we expected to see them and have been searching for years," Barnard said.

Scientists expected more black holes at our neighbor galaxy's center because Andromeda's bulge, the dense blob of stars at its middle, is larger than the Milky Way's.

NASA Mars Opportunity discovers clays favourable to Martian biology

The pale rock in the upper center of this image, about the size of a human forearm, includes a target called “Esperance,” which was inspected by NASA’s Mars Exploration Rover Opportunity.

Data from the rover’s alpha particle X-ray spectrometer (APXS) indicate that Esperance’s composition is higher in aluminum and silica, and lower in calcium and iron, than other rocks Opportunity has examined in more than nine years on Mars. 

Preliminary interpretation points to clay mineral content due to intensive alteration by water. 

Credit: NASA/JPL-Caltech/Cornell/Arizona 

Now nearly a decade into her planned 3 month only expedition to Mars, NASA's longest living rover Opportunity, struck gold and has just discovered the strongest evidence to date for an environment favourable to ancient Martian (organic) biology – and she has set sail hunting for a motherlode of new clues amongst fabulous looking terrain.

Barely two weeks ago in mid-May 2013, Opportunity's analysis of a new rock target named "Esperance" confirmed that it is composed of a "clay that had been intensely altered by relatively neutral pH water – representing the most favorable conditions for biology that Opportunity has yet seen in the rock histories it has encountered," NASA said in a statement.

The finding of a fractured rock loaded with clay minerals and ravaged by flowing liquid water in which life could have thrived amounts to a scientific home run for the golf cart sized rover!

"Water that moved through fractures during this rock's history would have provided more favorable conditions for biology than any other wet environment recorded in rocks Opportunity has seen," said the mission's principal investigator Prof. Steve Squyres of Cornell University, Ithaca, N.Y.

Opportunity accomplished the ground breaking new discovery by exposing the interior of Esperance with her still functioning Rock Abrasion Tool (RAT) and examining a pristine patch using the microscopic camera and X-Ray spectrometer on the end of her 3 foot long robotic arm.

The robot made the discovery at the conclusion of a 20 month long science expedition circling around a low ridge called "Cape York" – which she has just departed on a southerly heading trekking around the eroded rim of the huge crater named "Endeavour."

"Esperance was so important, we committed several weeks to getting this one measurement of it, even though we knew the clock was ticking."

Esperance stems from a time when the Red Planet was far warmer and wetter billions of years ago.

Close-Up of ‘Esperance’ After Abrasion by Opportunity 

This mosaic of four frames shot by the microscopic imager on the robotic arm of NASA’s Mars Exploration Rover Opportunity shows a rock target called “Esperance” after some of the rock’s surface had been removed by Opportunity’s rock abrasion tool, or RAT. 

The component images were taken on Sol 3305 on Mars (May 11, 2013). 

The area shown is about 2.4 inches (6 centimeters) across. 

Credit: NASA/JPL-Caltech/Cornell/USGS

NASA Mars Rover Curiosity: Discovers Conditions Once Suited for Ancient Life

An analysis of a rock sample collected by NASA's Curiosity rover shows ancient Mars could have supported living microbes.

Scientists identified sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon -- some of the key chemical ingredients for life -- in the powder Curiosity drilled out of a sedimentary rock near an ancient stream bed in Gale Crater on the Red Planet last month.

"A fundamental question for this mission is whether Mars could have supported a habitable environment," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington. "From what we know now, the answer is yes."

Clues to this habitable environment come from data returned by the rover's Sample Analysis at Mars (SAM) and Chemistry and Mineralogy (CheMin) instruments.

The data indicate the Yellowknife Bay area the rover is exploring was the end of an ancient river system or an intermittently wet lake bed that could have provided chemical energy and other favorable conditions for microbes.

The rock is made up of a fine-grained mudstone containing clay minerals, sulfate minerals and other chemicals. This ancient wet environment, unlike some others on Mars, was not harshly oxidizing, acidic or extremely salty.

The patch of bedrock where Curiosity drilled for its first sample lies in an ancient network of stream channels descending from the rim of Gale Crater. The bedrock also is fine-grained mudstone and shows evidence of multiple periods of wet conditions, including nodules and veins.

Curiosity's drill collected the sample at a site just a few hundred yards away from where the rover earlier found an ancient streambed in September 2012.

"Clay minerals make up at least 20 percent of the composition of this sample," said David Blake, principal investigator for the CheMin instrument at NASA's Ames Research Center in Moffett Field, Calif.

These clay minerals are a product of the reaction of relatively fresh water with igneous minerals, such as olivine, also present in the sediment. The reaction could have taken place within the sedimentary deposit, during transport of the sediment, or in the source region of the sediment. The presence of calcium sulfate along with the clay suggests the soil is neutral or mildly alkaline.

Scientists were surprised to find a mixture of oxidized, less-oxidized, and even non-oxidized chemicals, providing an energy gradient of the sort many microbes on Earth exploit to live. This partial oxidation was first hinted at when the drill cuttings were revealed to be gray rather than red.

"The range of chemical ingredients we have identified in the sample is impressive, and it suggests pairings such as sulfates and sulfides that indicate a possible chemical energy source for micro-organisms," said Paul Mahaffy, principal investigator of the SAM suite of instruments at NASA's Goddard Space Flight Center in Greenbelt, Md.

An additional drilled sample will be used to help confirm these results for several of the trace gases analyzed by the SAM instrument.

"We have characterized a very ancient, but strangely new 'gray Mars' where conditions once were favorable for life," said John Grotzinger, Mars Science Laboratory project scientist at the California Institute of Technology in Pasadena, Calif.

"Curiosity is on a mission of discovery and exploration, and as a team we feel there are many more exciting discoveries ahead of us in the months and years to come."

Scientists plan to work with Curiosity in the "Yellowknife Bay" area for many more weeks before beginning a long drive to Gale Crater's central mound, Mount Sharp.

Investigating the stack of layers exposed on Mount Sharp, where clay minerals and sulfate minerals have been identified from orbit, may add information about the duration and diversity of habitable conditions.

NASA Kepler Mission Discovers Tiny Planet System

The line up compares artist's concepts of the planets in the Kepler-37 system to the moon and planets in the solar system. 

The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. Kepler-37c, the second planet, is slightly smaller than Venus, measuring almost three-quarters the size of Earth. 

Kepler-37d, the third planet, is twice the size of Earth. Click image for full caption and larger size. Image credit: NASA/Ames/JPL-Caltech

NASA's Kepler mission scientists have discovered a new planetary system that is home to the smallest planet yet found around a star similar to our sun.

The planets are located in a system called Kepler-37, about 210 light-years from Earth in the constellation Lyra. The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. It is smaller than Mercury, which made its detection a challenge.

The moon-size planet and its two companion planets were found by scientists with NASA's Kepler mission to find Earth-sized planets in or near the "habitable zone," the region in a planetary system where liquid water might exist on the surface of an orbiting planet. However, while the star in Kepler-37 may be similar to our sun, the system appears quite unlike the solar system in which we live.

Astronomers think Kepler-37b does not have an atmosphere and cannot support life as we know it. The tiny planet almost certainly is rocky in composition. Kepler-37c, the closer neighboring planet, is slightly smaller than Venus, measuring almost three-quarters the size of Earth. Kepler-37d, the farther planet, is twice the size of Earth.

The first exoplanets found to orbit a normal star were giants. As technologies have advanced, smaller and smaller planets have been found, and Kepler has shown even Earth-size exoplanets are common.

"Even Kepler can only detect such a tiny world around the brightest stars it observes," said Jack Lissauer, a planetary scientist at NASA's Ames Research Center in Moffett Field, Calif. "The fact we've discovered tiny Kepler-37b suggests such little planets are common, and more planetary wonders await as we continue to gather and analyze additional data."

Kepler-37's host star belongs to the same class as our sun, although it is slightly cooler and smaller. All three planets orbit the star at less than the distance Mercury is to the sun, suggesting they are very hot, inhospitable worlds.

Kepler-37b orbits every 13 days at less than one-third Mercury's distance from the sun. The estimated surface temperature of this smoldering planet, at more than 800 degrees Fahrenheit (700 degrees Kelvin), would be hot enough to melt the zinc in a penny. Kepler-37c and Kepler-37d, orbit every 21 days and 40 days, respectively.

"We uncovered a planet smaller than any in our solar system orbiting one of the few stars that is both bright and quiet, where signal detection was possible," said Thomas Barclay, Kepler scientist at the Bay Area Environmental Research Institute in Sonoma, Calif., and lead author of the new study published in the journal Nature.

"This discovery shows close-in planets can be smaller, as well as much larger, than planets orbiting our sun."

The research team used data from NASA's Kepler space telescope, which simultaneously and continuously measures the brightness of more than 150,000 stars every 30 minutes.

When a planet candidate transits, or passes, in front of the star from the spacecraft's vantage point, a percentage of light from the star is blocked.

This causes a dip in the brightness of the starlight that reveals the transiting planet's size relative to its star.

The size of the star must be known in order to measure the planet's size accurately. To learn more about the properties of the star Kepler-37, scientists examined sound waves generated by the boiling motion beneath the surface of the star.

They probed the interior structure of Kepler-37's star just as geologists use seismic waves generated by earthquakes to probe the interior structure of Earth. The science is called astero-seismology.

The sound waves travel into the star and bring information back up to the surface. The waves cause oscillations that Kepler observes as a rapid flickering of the star's brightness.

Like bells in a steeple, small stars ring at high tones while larger stars boom in lower tones. The barely discernible, high-frequency oscillations in the brightness of small stars are the most difficult to measure.

This is why most objects previously subjected to astero-seismic analysis are larger than the sun.

NASA Themis Cluster discovers magnetic Spacequakes

Researchers using NASA's fleet of five THEMIS spacecraft have discovered a form of space weather that packs the punch of an earthquake and plays a key role in sparking bright Northern Lights. They call it "the spacequake."

A spacequake is a temblor in Earth's magnetic field. It is felt most strongly in Earth orbit, but is not exclusive to space. The effects can reach all the way down to the surface of Earth itself.

"Magnetic reverberations have been detected at ground stations all around the globe, much like seismic detectors measure a large earthquake," says THEMIS principal investigator Vassilis Angelopoulos of UCLA.

It's an apt analogy because "the total energy in a spacequake can rival that of a magnitude 5 or 6 earthquake," according to Evgeny Panov of the Space Research Institute in Austria. Panov is first author of a paper reporting the results in the April 2010 issue of Geophysical Research Letters (GRL).

In 2007, THEMIS discovered the precursors of spacequakes. The action begins in Earth's magnetic tail, which is stretched out like a windsock by the million mph solar wind. Sometimes the tail can become so stretched and tension-filled, it snaps back like an over-torqued rubber band. Solar wind plasma trapped in the tail hurtles toward Earth.

On more than one occasion, the five THEMIS spacecraft were in the line of fire when these "plasma jets" swept by. Clearly, the jets were going to hit Earth. But what would happen then? The fleet moved closer to the planet to find out.

"Now we know," says THEMIS project scientist David Sibeck of the Goddard Space Flight Center. "Plasma jets trigger spacequakes."

According to THEMIS, the jets crash into the geomagnetic field some 30,000 km above Earth's equator. The impact sets off a rebounding process, in which the incoming plasma actually bounces up and down on the reverberating magnetic field. Researchers call it "repetitive flow rebuffing."

It's akin to a tennis ball bouncing up and down on a carpeted floor. The first bounce is a big one, followed by bounces of decreasing amplitude as energy is dissipated in the carpet.

"We've long suspected that something like this was happening," says Sibeck. "By observing the process in situ, however, THEMIS has discovered something new and surprising."

Scottish scientists discovers cancer breakthrough

New DNA discovered in the city of Discovery

A PROTEIN has been discovered which could have major implications for cancer treatments, it emerged last night.

Researchers at the University of Dundee described the find as “molecular scissors” which repair damaged DNA in human cells, helping to prevent mutations leading to cancer.

The protein at the centre of the development is known as FAN1 and is present in each cell.

Yesterday, one of the experts behind the discovery explained how it might help further research against the killer disease.

John Rouse, of the university’s renowned College of Life Sciences, said the findings helped unlock a “major part of the puzzle”.

He added: “The DNA in our cells is like an instruction manual for the proper working of each cell.

“A major problem is that DNA becomes damaged regularly. If DNA damage is not fixed quickly then these instructions are changed and the result is mutations – undesirable changes in DNA – that can cause the cell to become abnormal.

“This is essentially what causes cancer.

“However, cells are very good at recognising when DNA has become damaged and they are good at finding DNA damage and repairing it.

“For example, cells can quickly detect breakages in DNA and quickly fix these breaks. Many different factors help this process but we still haven’t identified all of them or exactly how this process works. FAN1 carries out this task, and in this sense it acts like a ‘molecular scissors’.”

Japan Discovers new Superconductor Mechanisms

Japanese scientists say they've experimentally determined the mechanism underlying electron pair formation in iron-based, high-temperature superconductors.

The landmark finding by Riken Institute researchers involves the classical theory that superconductivity occurs when two electrons are bound together to form a pair, known as a Cooper pair, by lattice vibrations. That pairing mechanism has never been confirmed for high-temperature superconductors.

"The iron-based superconductors investigated by the research team Â… offer the greatest chance of solving this enigma," Riken said in a statement, noting the discovery breaks new ground by supporting a mechanism for electron pairing based not on lattice vibrations, as in other forms of superconductivity, but on magnetism.

"In providing a powerful constraint on theoretical models, the finding thus marks a major advance toward unraveling the mystery of high-temperature superconductivity," the company said.

NASA Radar Finds Ice Deposits at Moon's North Pole

NASA Radar Finds Ice Deposits at Moon's North Pole

Using data from a NASA radar that flew aboard India's Chandrayaan-1 spacecraft, scientists have detected ice deposits near the moon's north pole.

NASA's Mini-SAR instrument, a lightweight, synthetic aperture radar, found more than 40 small craters with water ice.

The craters range in size from 1 to 9 miles (2 to15 km) in diameter. Although the total amount of ice depends on its thickness in each crater, it's estimated there could be at least 1.3 trillion pounds (600 million metric tons) of water ice.

The Mini-SAR has imaged many of the permanently shadowed regions that exist at both poles of the Moons. These dark areas are extremely cold and it has been hypothesized that volatile material, including water ice, could be present in quantity here. The main science object of the Mini-SAR experiment is to map and characterize any deposits that exist.

Mini-SAR is a lightweight (less than 10 kg) imaging radar. It uses the polarisation properties of reflected radio waves to characterise surface properties. Mini-SAR sends pulses of radar that are left-circular polarised.

Typical planetary surfaces reverse the polarisation during the reflection of radio waves, so that normal echoes from Mini-SAR are right circular polarised. The ratio of received power in the same sense transmitted (left circular) to the opposite sense (right circular) is called the circular polarisation ratio (CPR).

Most of the Moon has low CPR, meaning that the reversal of polarisation is the norm, but some targets have high CPR. These include very rough, fresh surfaces (such as a young, fresh crater) and ice, which is transparent to radio energy and multiply scatters the pulses, leading to an enhancement in same sense reflections and hence, high CPR.

CPR is not uniquely diagnostic of either roughness or ice; the science team must take into account the environment of the occurrences of high CPR signal to interpret its cause.