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Light of an alien “super-Earth”

Artist's concept of the planet 55 Cancri e

Artist's concept of the planet 55 Cancri e, a world that orbits its star so closely—about 25 times closer than Mercury is to our Sun—that it is tidally locked with one face forever blistering under the heat of its star.

NASA’S SPITZER SPACE TELESCOPE has detected light emanating from a “super-Earth” planet beyond our Solar System for the first time. While the planet is not habitable, the detection is a historic step toward the eventual search for signs of life on other planets.

While no current telescope is able to show us an image of the planet, Spitzer can detect the spectrum of light coming from it.

The planet, called 55 Cancri e, falls into a class of planets termed super Earths, which are more massive than our home world but lighter than giant planets like Neptune. Fifty-five Cancri e is about twice as big and eight times as massive as Earth. The planet orbits a bright star, called 55 Cancri, in a mere 18 hours.

Previously, Spitzer and other telescopes were able to study the planet by analysing how the light from 55 Cancri changed as the planet passed in front of the star. In the new study, Spitzer measured how much infrared light comes from the planet itself.

The results reveal the planet is likely dark and its sun-facing side is more than 1,700 degrees Celsius, hot enough to melt metal.

Distant water world

The new information is consistent with a prior theory that 55 Cancri e is a water world: a rocky core surrounded by a layer of water in a “supercritical” state where it is both liquid and gas, and topped by a blanket of steam.

“It could be very similar to Neptune, if you pulled Neptune in toward our Sun and watched its atmosphere boil away,” said Michael Gillon of Universite de Liege in Belgium, principal investigator of the research, which appears in the Astrophysical Journal. The lead author is Brice-Olivier Demory of the Massachusetts Institute of Technology in Cambridge.

Artist's impression of the Spitzer Space Telescope

Artist's impression of the Spitzer Space Telescope

The 55 Cancri system is relatively close to Earth at 41 light-years away. It has five known planets, with 55 Cancri e being the closest to the star and tidally locked, so one side always faces the star. Spitzer discovered the star-facing side is extremely hot, indicating the planet probably does not have a substantial atmosphere to carry the sun’s heat to the unlit side.

Direct measurements

In 2005, Spitzer became the first telescope to detect light from a planet beyond our Solar System. To the surprise of many, the observatory saw the infrared light of a “hot Jupiter,” a gaseous planet much larger than the solid 55 Cancri e.

Since then, other telescopes, including NASA’s Hubble and Kepler space telescopes, have performed similar feats with gas giants using the same method.

In this method, a telescope gazes at a star as a planet circles behind it. When the planet disappears from view, the light from the star system dips ever so slightly, but enough that astronomers can determine how much light came from the planet itself. This information reveals the temperature of a planet, and, in some cases, its atmospheric components. Most other current planet-hunting methods obtain indirect measurements of a planet by observing its effects on the star.

During Spitzer’s ongoing extended mission, steps were taken to enhance its unique ability to see exoplanets, including 55 Cancri e. Those steps, which included changing the cycling of a heater and using an instrument in a new way, led to improvements in how precisely the telescope points at targets.

NASA’s James Webb Space Telescope, scheduled to launch in 2018, likely will be able to learn even more about the planet’s composition. The telescope might be able to use a similar infrared method as Spitzer to search other potentially habitable planets for signs of molecules possibly related to life.

Adapted from information issued by NASA / JPL-Caltech.

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Three space missions extended

Artist's concepts of Spitzer, Planck and Kepler

Artist's concepts of Spitzer, Planck and Kepler. NASA extended Spitzer and Kepler for two additional years; and the US portion of Planck, a European Space Agency mission, for one year. (Relative sizes not to scale.)

NASA HAS EXTENDED three missions—Kepler, the Spitzer Space Telescope and the US portion of the European Space Agency’s Planck mission—as a result of the 2012 Senior Review of Astrophysics Missions.

“This means scientists can continue using the three spacecraft to study everything from the birth of the universe with Planck, and galaxies, stars, planets, comets and asteroids with Spitzer, while Kepler is determining what percentage of Sun-like stars host potentially habitable Earth-like planets,” said Michael Werner, the chief scientist for astronomy and physics at JPL.

Kepler has been approved for extension through fiscal year 2016, providing four additional years to find Earth-size planets in the habitable zone—the region in a planetary system where liquid water could exist on the surface of the orbiting planet—around Sun-like stars in our galaxy.

Spitzer, launched in 2003, will continue to provide the astronomical community with its unique infrared images for another two years. It has continued to explore the cosmos since running out of coolant, as expected, in 2009.

Among its many duties during its “warm mission”, the observatory is probing the atmospheres of planets beyond our Sun and investigating the glow of some of the most distant galaxies known. As requested by the project, Spitzer received two additional years of operations.

NASA will fund an additional year of US participation in the European Space Agency’s Planck mission. Planck, launched in 2009, is gathering data from the very early universe, shortly after its explosive birth in a big bang. Planck’s observations are yielding insight into the origin, evolution and fate of our universe.

More information:

Kepler mission

Spitzer Space Telescope

Planck mission

Adapted from information issued by JPL. Images courtesy NASA / JPL-Caltech.

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Galaxy at the dawn of time

Galaxy GN-108036

One of the most distant galaxies known, called GN-108036, is seen 750 million years after the Big Bang. The galaxy's light took 12.9 billion years to reach us. Infrared observations taken by NASA's Spitzer and Hubble space telescopes show it to be surprisingly bright, thought to result from an extreme burst of star formation

  • Galaxy seen as it was 750 million years after the Big Bang
  • Observations suggest it is forming stars at a furious rate

ASTRONOMERS USING NASA’S Spitzer and Hubble space telescopes have discovered that one of the most distant galaxies known is churning out stars at a shockingly high rate. The blob-shaped galaxy, called GN-108036, is the brightest galaxy found to date at such great distances.

The galaxy, which was discovered and confirmed using ground-based telescopes, is 12.9 billion light-years away.

Data from Spitzer and Hubble were used to measure the galaxy’s high star production rate, equivalent to about 100 Suns per year.

For reference, our Milky Way galaxy is about five times larger and 100 times more massive than GN-108036, but makes roughly 30 times fewer stars per year.

“The discovery is surprising because previous surveys had not found galaxies this bright so early in the history of the universe,” said Mark Dickinson of the US National Optical Astronomy Observatory in Arizona. “Perhaps those surveys were just too small to find galaxies like GN-108036.”

“It may be a special, rare object that we just happened to catch during an extreme burst of star formation.”

Seen shortly after the Big Bang

The international team of astronomers, led by Masami Ouchi of the University of Tokyo, Japan, first identified the remote galaxy after scanning a large patch of sky with the Subaru Telescope atop Mauna Kea in Hawaii.

Its great distance was then carefully confirmed with the W.M. Keck Observatory, also on Mauna Kea.

“We checked our results on three different occasions over two years, and each time confirmed the previous measurement,” said Yoshiaki Ono of the University of Tokyo, lead author of a new paper reporting the findings in the Astrophysical Journal.

Spitzer (left) and Hubble space telescopes

The Spitzer (left) and Hubble space telescopes were used to measure the galaxy's redshift, a indication of how far away it is.

GN-108036 lies near the very beginning of time itself, a mere 750 million years after our universe formed 13.7 billion years ago in an explosive “Big Bang.”

Its light has taken 12.9 billion years to reach us, so we are seeing it as it existed in the very distant past.

Remarkable redshift

Astronomers refer to an object’s distance by a number called its “redshift,” which is a measure of how much its light has been stretched to longer, redder wavelengths due to the expansion of the universe.

Objects with larger redshifts are farther away and are seen further back in time.

GN-108036 has a redshift of 7.2. Only a handful of galaxies have confirmed redshifts greater than 7, and only two of these have been reported to be more distant than GN-108036.

Infrared observations from Spitzer and Hubble were crucial for measuring the galaxy’s star-formation activity. Astronomers were surprised to see such a large burst of star formation because the galaxy is so small and from such an early cosmic era.

Back when galaxies were first forming, in the first few hundreds of millions of years after the Big Bang, they were much smaller than they are today, having yet to bulk up in mass.

During this epoch, as the universe expanded and cooled after its explosive start, hydrogen atoms permeating the cosmos formed a thick fog that was opaque to ultraviolet light. This period, before the first stars and galaxies had formed and illuminated the universe, is referred to as the “dark ages.”

The era came to an end when light from the earliest galaxies burned through, or “ionised,” the opaque gas, causing it to become transparent. Galaxies similar to GN-108036 may have played an important role in this event.

Adapted from information issued by NASA / JPL-Caltech / STScI / University of Tokyo.

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World’s biggest telescope a step closer

Artist's impression of the European Extremely Large Telescope

Artist's impression of the European Extremely Large Telescope

A TELESCOPE TO DWARF ALL OTHERS is on the road to being fully approved in mid-2012, with much of the funding secured and work commencing on the road that will provide access to the remote site in Chile.

The European Extremely Large Telescope (E-ELT) will be an optical/infrared telescope with a main mirror 39.3 metres wide. Today’s current largest telescopes have mirrors around the 10-metre mark.

The European Southern Observatory’s (ESO) huge, 1.802 billion Euro facilitywill be built at Cerro Armazones in Chile’s high Atacama desert.

Artist's impression of the E-ELT alongside the Sydney Opera House

Artist's impression of the E-ELT alongside the Sydney Opera House, to give an idea of scale.

The initial work approved this week includes preparations for the road that will link to the site, and commencement of work on one on the most challenging parts of the telescope…the M4 mirror, an “adaptive optics” mirror that will help to remove the blurring effect of Earth’s atmosphere.

“The E-ELT is starting to become reality,” says the ESO Director General, Tim de Zeeuw. “However, with a project of this size it is expected that approval of the extra expenditure will take time … preparatory work must start now in order for the project to be ready for a full start of construction in 2012.”

Final approval for the E-ELT project is expected to be granted next year.

This video from last year explains more about the amazing E-ELT and the site at which it will be built:

Story by Jonathan Nally. Images and video courtesy ESO.

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Rain of comets in alien star system

Artist's conception of the Eta Corvi star system

This artist's conception illustrates a storm of comets in the Eta Corvi star system. Evidence for this barrage comes from NASA's Spitzer Space Telescope, whose infrared detectors picked up indications that one or more comets was recently torn to shreds after colliding with a rocky body.

NASA’S SPITZER SPACE TELESCOPE has detected signs that icy bodies are raining down in an alien planetary system. The downpour resembles our own Solar System several billion years ago during a period known as the ‘Late Heavy Bombardment,’ when water and other life-forming ingredients may have been brought to Earth.

During this epoch, comets and other frosty objects that were flung inwards from the outer Solar System pummelled the inner planets. The barrage scarred our Moon and produced large amounts of dust.

Now Spitzer has spotted a band of dust around a nearby star called Eta Corvi that strongly matches the contents of an obliterated giant comet. This dust is located close to Eta Corvi, where Earth-sized worlds could exist, suggesting a collision took place between a planet and one or more comets.

The Eta Corvi system is approximately one billion years old, which researchers think is about the right age for such a hailstorm.

Similar to our Solar System

Astronomers used Spitzer’s infrared detectors to analyse the light coming from the dust around Eta Corvi. Certain chemical fingerprints were observed, including water ice, organics and rock, which indicate a giant comet source.

The light signature emitted by the dust around Eta Corvi also resembles the Almahata Sitta meteorite, which fell to Earth in fragments across Sudan in 2008. The similarities between the meteorite and the object obliterated in Eta Corvi imply a common birthplace in their respective planetary systems.

A second, more massive ring of colder dust located at the far edge of the Eta Corvi system seems like the proper environment for a reservoir of cometary bodies. This bright ring, discovered in 2005, is about 150 times the distance from Eta Corvi as the Earth is from the Sun.

Our Solar System has a similar region, known as the Kuiper Belt, where icy and rocky leftovers from planet formation linger. The new Spitzer data suggest that the Almahata Sitta meteorite may have originated in our own Kuiper Belt.

Adapted from information issued by NASA / JPL-Caltech / R. Hurt (SSC).

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Ancient supernova seen in a new light

RCW 86

This is all that remains of a supernova explosion that was seen by Chinese astronomers in the year 185 CE. The remnant gas cloud is called RCW 86, and is approximately 8,000 light-years from Earth.

A TWISTED AND TANGLED GAS CLOUD is all that remains of the oldest documented example of a supernova, called RCW 86.

Chinese stargazers witnessed the event in 185 CE, documenting a mysterious ‘guest star’ that remained in the sky for eight months.

The image combines data from four different space telescopes to create a multi-wavelength view.

X-ray images from the European Space Agency’s XMM-Newton Observatory and NASA’s Chandra X-ray Observatory are combined to form the blue and green colours in the image. The X-rays show the interstellar gas that has been heated to millions of degrees by the passage of the shock wave from the supernova.

Infrared data from NASA’s Spitzer Space Telescope, as well as NASA’s Wide-Field Infrared Survey Explorer (WISE) are shown in yellow and red, and reveal dust radiating at a temperature of several hundred degrees below zero, warm by comparison to normal dust in our Milky Way galaxy.

By studying the X-ray and infrared data together, astronomers were able to determine that the cause of the explosion witnessed nearly 2,000 years ago was a Type Ia supernova, in which an otherwise-stable white dwarf, or dead star, was pushed beyond the brink of stability when a companion star dumped material onto it.

Furthermore, scientists used the data to solve another mystery surrounding the remnant—how it got to be so big in such a short amount of time.

By blowing out a ‘wind’ prior to exploding, the white dwarf was able to clear out a huge ‘cavity,’ a region of very low-density surrounding the system. The explosion was able to expand into this cavity much faster than it otherwise would have.

RCW 86 is approximately 8,000 light-years away.

Adapted from information issued by NASA / JPL-Caltech / B. Williams (NCSU).

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Journey to the Centre of the Galaxy

HIDING BEHIND DUST in the direction of the constellations Sagittarius and Scorpius is the centre of our own Milky Way galaxy, over 25,000 light years away. The infrared vision of NASA’s Spitzer Space Telescope and the European Space Agency’s Herschel Space Observatory sees through the dust showing us this strange and tumultuous region.

Adapted from information issued by NASA / JPL-Caltech / ESA.

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Star spangled nebula

Spitzer image of the North American Nebula

This new Spitzer Space Telescope infrared image of the North American Nebula reveals a multitude of young stars, ordinarily hidden in visible wavelength images by veils of dust.

  • Nebula shaped like the North American continent
  • Infrared view pierces the veil of dust, revealing stars
  • Thousands of young stars seen in Spitzer telescope image

STARS AT ALL STAGES of development, from dusty little tots to young adults, are on display in a new image from NASA’s Spitzer Space Telescope.

This cosmic community is called the North American Nebula. At visible light wavelength pictures, the region resembles the North American continent, with the most striking resemblance being the Gulf of Mexico.

But in Spitzer’s infrared view, the continent disappears. Instead, a swirling landscape of dust and young stars comes into view.

“One of the things that makes me so excited about this image is how different it is from the visible image, and how much more we can see in the infrared than in the visible,” said Luisa Rebull of NASA’s Spitzer Science Centre at the California Institute of Technology.

Rebull is lead author of a paper about the observations, accepted for publication in the Astrophysical Journal Supplement Series.

“The Spitzer image reveals a wealth of detail about the dust and the young stars here.”

Dusty environment

Rebull and her team have identified more than 2,000 new, candidate young stars in the region. There were only about 200 known before.

Because young stars grow up surrounded by blankets of dust, they are hidden in visible-light images. Spitzer’s infrared detectors pick up the glow of the dusty, buried stars.

Visible and infrared views of the North American Nebula

Spot the difference. Visible light (left) and infrared wavelength (right) views of the North American Nebula, taken by the Digitised Sky Survey and NASA's Spitzer Space Telescope, respectively. Infrared can see through the dust and gas.

A star is born inside a collapsing ball of gas and dust. As the material collapses inward, it flattens out into a disc that spins around together with the forming star like a spinning top. Jets of gas shoot perpendicularly away from the disc, above and below it.

As the star ages, planets are thought to form out of the disc—material clumps together, ultimately growing into mature planets. Eventually, most of the dust dissipates, aside from a tenuous ring similar to the one in our Solar System, referred to as Zodiacal dust.

Family portrait

The new Spitzer image reveals all the stages of a star’s young life, from the early years when it is swaddled in dust to early adulthood, when it has become a young parent to a family of developing planets. Sprightly “toddler” stars with jets can also be identified in Spitzer’s view.

“This is a really busy area to image, with stars everywhere, from the North American complex itself, as well as in front of and behind the region,” said Rebull.

Young stars in the "Gulf of Mexico" part of the North American Nebula

A cluster of young stars in the "Gulf of Mexico," part of the North American Nebula.

“We refer to the stars that are not associated with the region as contamination,” Rebull added. “With Spitzer, we can easily sort this contamination out and clearly distinguish between the young stars in the complex and the older ones that are unrelated.”

See the full-size image here.

More mysteries to solve

The North American Nebula still has a mystery surrounding it, involving its power source. Nobody has been able to identify the group of massive stars that is thought to be dominating and illuminating the nebula.

The Spitzer image, like images from other telescopes, hints that the missing stars are lurking behind the Gulf of Mexico portion of the nebula. This is evident from the illumination pattern of the nebula, especially when viewed with the detector on Spitzer that picks up 24-micron infrared light. That light appears to be coming from behind the Gulf of Mexico’s dark tangle of clouds, in the same way that sunlight creeps out from behind a rain cloud.

The nebula’s distance from Earth is also a mystery. Current estimates put it at about 1,800 light-years from Earth.

Adapted from information issued by NASA / JPL-Caltech. Images courtesy NASA / JPL-Caltech / L. Rebull (SSC / Caltech).

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Diamond life for distant planet

Artist's concept of planet WASP-12b

Artist's concept of the searing-hot gas planet WASP-12b (orange orb) and its star. Scientists have discovered that the planet has more carbon than oxygen, making it the first carbon-rich planet ever observed. Astronomers say that carbon-rich gas planets could have abundant diamond in their interiors.

  • Planet WASP-12b is 1,200 light-years from Earth
  • Most carbon-rich planet yet discovered
  • Daytime temperature is hot enough to melt steel

ASTRONOMERS HAVE DISCOVERED that a huge, searing-hot planet orbiting another star is loaded with an unusual amount of carbon.

The planet, a gas giant named WASP-12b, is the first carbon-rich world ever observed.

The discovery was made using NASA’s Spitzer Space Telescope, along with previously published ground-based observations.

“This planet reveals the astounding diversity of worlds out there,” said Nikku Madhusudhan of the Massachusetts Institute of Technology, Cambridge, lead author of a report in the December 9 issue of the journal Nature. “Carbon-rich planets would be exotic in every way—formation, interiors and atmospheres.”

It’s possible that WASP-12b might harbour graphite, diamond, or even a more exotic form of carbon in its interior, beneath its gaseous layers.

Astronomers don’t currently have the technology to observe the cores of exoplanets (ie. planets orbiting stars beyond our Sun) but their theories hint at these intriguing possibilities.

The research also supports theories that carbon-rich rocky planets much less massive than WASP-12b could exist around other stars. Our Earth has rocks like quartz and feldspar, which are made of silicon and oxygen plus other elements. A carbon-rich rocky planet could be a very different place.

“A carbon-dominated terrestrial world could have lots of pure carbon rocks, like diamond or graphite, as well as carbon compounds like tar,” said Joseph Harrington of the University of Central Florida, in Orlando, who is the principal investigator of the research.

Mountains made of diamond

Carbon is a common component of planetary systems and a key ingredient of life on Earth. Astronomers often measure carbon-to-oxygen ratios to get an idea of a star’s chemistry. Our Sun has a carbon-to-oxygen ratio of about one to two, which means it has about half as much carbon as oxygen.

Spitzer plot of molecules in atmosphere of WASP-12b

Data from NASA's Spitzer Space Telescope indicates that the atmosphere of planet WASP-12b has carbon monoxide, excess methane, and not much water vapour. The results demonstrate that WASP-12b is the first known carbon-rich planet.

WASP-12b is the first planet ever to have its carbon-to-oxygen ratio measured at greater than one (the actual ratio is most likely between one and two). This means the planet has excess carbon, some of which is in the form of atmospheric methane.

“When the relative amount of carbon gets that high, it’s as though you flip a switch, and everything changes,” said Marc Kuchner, an astronomer at NASA Goddard Space Flight Centre, who helped develop the theory of carbon-rich rocky planets but is not associated with the study.

“If something like this had happened on Earth, your expensive engagement ring would be made of glass, which would be rare, and the mountains would all be made of diamonds.”

WASP-12b derives its name from the consortium that found it, the Wide Angle Search for Planets. It is 1.4 times as massive as Jupiter and located roughly 1,200 light-years away from Earth.

This blistering world whips around its star in a little over a day, with one side always facing the star. It is so close to its star that the star’s gravity stretches the planet into an egg-like shape. What’s more, the star’s gravity is siphoning mass off the planet into a thin disc that orbits around with it.

The Spitzer data also reveal more information about WASP-12b’s temperature. The world was already known to be one of the hottest exoplanets found so far; the new observations indicate that the side that faces the star is 2,300 degrees Celsius. That’s more than hot enough to melt steel.

Adapted from information issued by NASA / JPL. Images courtesy NASA / JPL-Caltech / N. Madhusudhan (Princeton University).

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Twin stars could doom planets

planetary collision

This artist's concept illustrates an imminent planetary collision around a pair of double stars. NASA's Spitzer Space Telescope found evidence that such collisions could be common around certain types of tight binary star systems.

  • Dust cloud spotted circling stellar twins
  • Could be the remains of planetary collisions

Tight double-star systems might not be the best places for life to spring up, according to a new study using data from NASA’s Spitzer Space Telescope.

The infrared observatory spotted a surprisingly large amount of dust around three mature, close-orbiting star pairs. Where did the dust come from? Astronomers say it might be the aftermath of tremendous planetary collisions.

“This is real-life science fiction,” said Jeremy Drake of the Harvard-Smithsonian Centre for Astrophysics, Cambridge, Mass. “Our data tell us that planets in these systems might not be so lucky—collisions could be common.”

“It’s theoretically possible that habitable planets could exist around these types of stars, so if there happened to be any life there, it could be doomed.”

Drake is the principal investigator of the research, published in the August19 issue of the Astrophysical Journal Letters.

The particular class of binary, or double, stars in the study are about as snug as stars get. Named RS Canum Venaticorums, or RS CVns for short, they are separated by only about 3.2 million kilometres (2 million miles), or two percent of the distance between Earth and our Sun.

The stellar pairs orbit around each other every few days, with one face on each star perpetually locked and pointed toward the other.

binary star

Artist's concept of a tight pair of stars and a surrounding disc of dust—most likely the shattered remains of planetary smash-ups. Using NASA's Spitzer Space Telescope, scientists found dusty evidence for such collisions around three sets of stellar twins.

Colliding planets

The close-knit stars are similar to the Sun in size and are probably about a billion to a few billion years old—roughly the age of our Sun when life first evolved on Earth.

But these stars spin much faster, and, as a result, have powerful magnetic fields, and giant, dark spots. The magnetic activity drives strong stellar winds—gale-force versions of the solar wind—that slow the stars down, pulling the twirling duos closer over time.

And this is where the planetary chaos may begin.

As the stars cosy up to each other, their gravitational influences change, and this could cause disturbances to planetary bodies orbiting around both stars. Comets and any planets that may exist in the systems would start jostling about and banging into each other, sometimes in powerful collisions.

This includes planets that could theoretically be circling in the double stars’ habitable zone, a region where temperatures would allow liquid water to exist.

Though no habitable planets have been discovered around any stars beyond our Sun at this point in time, tight double-star systems are known to host planets; for example, one system not in the study, called HW Vir, has two gas-giant planets.

“These kinds of systems paint a picture of the late stages in the lives of planetary systems,” said Marc Kuchner, a co-author from NASA Goddard Space Flight Centre. “And it’s a future that’s messy and violent.”

Spitzer space telescope

An artist's impression of the Spitzer Space Telescope, which studies the cosmos at infrared wavelengths.

Not a fluke

Spitzer spotted the infrared glow of hot dusty discs, about the temperature of molten lava, around three such tight binary systems. One of the systems was originally flagged as having a suspicious excess of infrared light in 1983 by the Infrared Astronomical Satellite.

In addition, researchers using Spitzer recently found a warm disc of debris around another star that turned out to be a tight binary system.

The astronomy team says that dust normally would have dissipated and blown away from the stars by this mature stage in their lives. They conclude that something—most likely planetary collisions—must therefore be kicking up the fresh dust.

In addition, because dusty discs have now been found around four, older binary systems, the scientists know that the observations are not a fluke. Something chaotic is very likely going on.

If any life forms did exist in these star systems, and they could look up at the sky, they would have quite a view. Marco Matranga, first author of the paper, from the Harvard-Smithsonian Centre for Astrophysics and now a visiting astronomer at the Palermo Astronomical Observatory in Sicily, said, “The skies there would have two huge suns, like the ones above the planet Tatooine in Star Wars”.

Adapted from information issued by SAO / NASA / JPL-Caltech.

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