Tag Archives: solar system

Giant Comets Pose Threat To Life On Earth

Huge comets called centaurs deserve greater recognition as potential destroyers of life on Earth, according to a team of astronomers from the Armagh Observatory and the University of Buckingham. Measuring 50 to 100 kilometers (30 to 60 miles) across, these enormous masses of ice and rock have been identified in their hundreds over recent decades in the trans-Neptunian region the area beyond Neptune, which is the outermost planet in the Solar System.

However, these centaurs can make their way towards the inner planets as their orbits become deflected by the gravitational fields of Neptune, Uranus, and Saturn. Publishing a review of their research in Astronomy and Geophysics,the team estimates that centaurs are likely to cross the Earths orbit every 40,000 to 100,000 years.

Depending on the size, composition, and distance of a given comet, its effects on terrestrial ecosystems are likely to be highly variable. Because centaurs are thought to be unstable, the authors expect the majority of these effects to be caused by dust and other small fragments that result from the disintegration of the comets.

They estimate that a single centaur measuring 100 kilometers (60 miles) could contain about 100 times the mass of all the Earth-crossing asteroids detected to date. This translates to an awful lot of dust, leading the researchers to suggest that comets of this size could fill the Earths atmosphere with tiny particles, reducing the amount of sunlight that can pass through to roughly the level of moonlight, for up to 100,000 years. This, they say, would put an end to commercial agriculture.

A map of the Solar System, showing the orbits of several planets. In red are the orbits of 22 centaurs. In yellow are the orbits of 17 trans-Neptunian objects. Duncan Steel/Royal Astronomical Society

Additionally, larger fragments which could extend for several kilometers in length may generate catastrophic impacts, similar to that which is believed to have led to the extinction of the dinosaurs. According to the report, several such collisions may have occurred in the past, with the authors citing craters in the Gulf of Mexico, Ukraine, Siberia and Chesapeake Bay as likely candidates for centaur impact sites.

Given the probability of a centaur crossing Earths orbit at some point in the future, and the sheer volume of debris caused by the disintegration of these comets, the team claims that some level of impact is inevitable, although the nature and extent of the effects are likely to depend on various factors.

At present, attempts to quantify Earths risk of being affected by a collision are centered around NASAs Spaceguard initiative, which seeks to map up to 90 percent of near-Earth objects (NEOs) larger than 1 kilometer (0.6 miles). This programfocuses mainly on the asteroid belt that sits between Mars and Jupiter, although Professor Bill Napier, who helped to conduct this research, is now calling for the scope of this search to be extended to the outer reaches of the Solar System.

Our work suggests we need to look beyond our immediate neighborhood and look out beyond the orbit of Jupiter to find centaurs, he said in a statement. If we are right, then these distant comets could be a serious hazard, and it’s time to understand them better.

Read more: http://www.iflscience.com/space/giant-comets-pose-potential-threat-earth

Astronomers Think They’ve Discovered A Neptune-Sized Ninth Planet Beyond Pluto

In 2005, the discovery of the dwarf planet Eris by Caltech astronomer Mike Brown and his colleagues ultimately led to Pluto being demoted as the ninth planet of the Solar System a year later. Brown took to his status as the man who relegated Pluto with aplomb; his handle on Twitter is, rather appropriately, plutokiller.

But new research, published today in The Astronomical JournalbyBrown and his colleague Konstantin Batygin, is sure to cause a stir. He is proposing the existence of a real ninth planet of the Solar System, dubbed Planet Nine and ostentatiously nicknamed Phattie,that would be almost the size of Neptune.

The planet has not been observed; rather, the astronomers have put together a mathematical model that infers its existence. We have a gravitational signature of a giant planet in the outer Solar System, Batygin told Nature. But interestingly, they say that some of the most powerful telescopes on Earth at the moment may be capable of spotting it and it may already be hiding in existing images.

Evidence for Planet Nine comes from the observed motion of objects in the Kuiper Belt, a vast region of comets beyond the orbit of Pluto. According to the paper, it suggests there is a planet ten times the mass of Earth on a hugely elliptical orbit around the Sun, completing an orbit every 10,000 to 20,000 years and never getting closer than 200 times the Earth-Sun distance.

Ahefty degree of skepticism is certainly needed, though. After all, the infamous Planet X and the mythical Nibiru have been circling in astronomy and conspiracy circles for years. Planet Nine has not even been seen yet; its too early to say it exists for definite. But Brown himself is confident.

OK, OK, I am now willing to admit: I DO believe that the solar system has nine planets, he wrote on Twitter.

Shown is the predicted elliptical orbit for Planet Nine, and other orbits for known distant objects in the Solar System. Caltech/R. Hurt (IPAC)

In their paper, Brown and Batygin say there is only a 0.007 percent chance that the observed clustering of Kuiper Belt Objects (KBOs) is due to chance,suggesting another origin. We find that the observed orbital alignment can be maintained by a distant eccentric planet with mass [greater than 10 Earths], they wrote. The planet could also explain the elliptical orbits of dwarf planets like Sedna.

One possible explanation for the planets existence, according to the authors, is that it was a giant planet core that was ejected during the early Solar System, something that may be common in planetary systems.

The discovery of a ninth planet in the Solar System would be huge, and thats an understatement. Astronomers have previously predicted the existence of hundreds of dwarf planets beyond the orbit of Pluto in the Kuiper Belt, but so far no solid theories exist for a large planet like Planet Nine.

This paper is sure to be pored over, scrutinized, and perhaps even discredited, so dont expect to have to learn a new mnemonic for the planets any time soon. But be prepared; the man who killed Pluto might just have given a new lease of life to the hypothesized existence of a ninth world in our Solar System.

For the first time in over 150 years, there is solid evidence that the Solar Systems planetary census is incomplete, said Batygin in a statement.

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Read more: http://www.iflscience.com/possible-ninth-planet-solar-system-discovered

Astronomers Determine Saturn’s Location With Astounding Accuracy

By combining signals from NASA’s Cassini spacecraft with observations from the National Radio Astronomy Observatory’s (NRAO) very long baseline array (VLBA), scientists have been able to accurately identify Saturn’s position to within a single mile. This information will be useful in understanding the orbits of planets in the outer solar system, and will have other widespread implications for future research. The study was led by Dayton Jones of Jet Propulsion Laboratory, and the paper was published in The Astronomical Journal. The work was also presented this week at the 225th meeting of the American Astronomical Meeting.

“This work is a great step toward tying together our understanding of the orbits of the outer planets of our solar system and those of the inner planets,” Jones said in a press release.

The VLBA is a network of ten radio antennae that span across North America, from Hawaii to the Virgin Islands. Working in concert, the array is able to resolve incredible detail across great distances. In this case, it was able to very accurately track the radio signal from the Cassini spacecraft, which has been orbiting Saturn for the last ten years. 

Using five years’ worth of Cassini’s signaling data, the VLBA was able to resolve Saturn’s location to an area smaller than two miles, which is roughly 50-100 times more accurate than previous calculations. This greatly clarifies Saturn’s ephemeris, which is the table that states a celestial body’s predicted location at any given point in time. 

“An accurate ephemeris is one of the basic tools of astronomy, and this work is a great step toward tying together our understanding of the orbits of the outer planets and those of the inner planets,” Jones explained to the NRAO. “The orbits of the inner planets are well tied together, but those of the outer planets, including Saturn, have not been tied as well to each other or to those of the inner planets.”

By better understanding Saturn’s orbit and where it will be at a given time in relation to other objects, astronomers can take advantage of research opportunities. These include using distant light to study its rings, the better timing of experiments with pulsars, and even improving tests regarding Einstein’s theory of general relativity using quasars. The updated ephemeris will also be quite useful for better navigation of spacecrafts, and has already improved the course of Cassini’s mission to make more meaningful measurements and observations.

The researchers hope to replicate the success from this study in the future with Jupiter. The VLBA will track the radio signals from NASA’s Juno spacecraft, which is set to insert into Jupiter’s orbit in July of 2016. As Jupiter and Saturn are the two largest planets in our solar system, having accurate ephemerides for these planets will be a tremendous accomplishment and greatly improve future scientific research and spacecraft missions.

Read more: http://www.iflscience.com/space/astronomers-determine-saturn-s-location-astounding-accuracy

Solution To Voyager 1 Magnetic Field Mystery Suggests It Is Not Quite In Interstellar Space

Researchers say theyhave solved a key mystery regarding Voyager 1 leaving the Solar System. It was believed to have passed beyond the influence of the Sun (the heliosphere) into interstellar space in 2013, the first spacecraft ever to do so, but measurements of the surrounding magnetic field since have caused some controversy.

Essentially, the magnetic field observed by Voyager 1 is tilted at 40 degrees to the expected interstellar magnetic field. This latest study, published in the Astrophysical Journal Letters, explains the anomaly by suggesting that the orientation of the magnetic field is being pushed and stretched by the solar wind. The authors predict that it will take 10years for the spacecraft to pass into a region of space where the surrounding magnetic field is no longer influenced at all by the Sun.

“If you think of the magnetic field as a rubber band stretched around a beach ball, that band is being deflected around the heliopause [where the solar wind stops],” lead author of the study,Nathan Schwadron of the University of New Hampshire, said in a statement.

The direction of the interstellar magnetic field was estimated using data from NASAs Interstellar Boundary Explorer (IBEX) spacecraft. It observed a ribbon of hydrogen atoms, dubbed the IBEX ribbon, just beyond the Solar System that seem to indicate its direction. Voyager 1s different readings, therefore, were a cause for some confusion.

Now,using readings from the Voyager spacecraftnamely thatit has observed a change in magnetic field orientation of a few degrees every yearthe researchers have proposed the tilted magnetic field theory.

Artist’s impression of the Voyager spacecraft. NASA.

The lack of a significant change in the magnetic field when Voyager crossed beyond the Solar System had also been somewhat of a mystery, but this theory seems to show that it is a gradual change, and not a sudden changelike other variables such as the dramatic change in particles, 40 times greater, observed beyond the boundary.

The results suggest that Voyager 1 is not quite in true interstellar space yet, although Schwardon told IFLScience itwas a matter of philosophy. Instead, Voyager 1 is in a sort of purgatory region which Schwardon called the outer heliosheath, where the solar wind and interstellar medium interact. It will not be until Voyager 1 reaches the so-called pristine region of the interstellar medium that is unaffected by solar wind in 10years that it will truly be beyond the Solar Systems influence.

For all intents and purposes, though, NASA says that Voyager 1 has entered interstellar space because it has crossed the heliosphere, the bubble of solar wind around the Solar System. In 2025, the researchers expect Voyager 1 to record the same magnetic field direction in the pristine interstellar medium as the IBEX ribbon, an estimation supported by observations from the Ulysses and SOHO spacecraft.

Then, Voyager 1 will truly, almost certainly, be entirely in interstellar space and out of reach of the Sun.

Image in text: Artist’s impression of the Voyager spacecraft. NASA.

Read more: http://www.iflscience.com/space/solution-voyager-1-magnetic-field-mystery-suggests-it-not-quite-interstellar-space

New Horizons Begins Life After Pluto By Studying Distant Solar System Object

After the New Horizons spacecraft made its historic flyby of Pluto in July 2015, the plan was always to send it further out of the Solar System to study other objects. Now, the spacecraft has returned the first science from such observations.

New Horizons observed a Kuiper Belt object (KBO) on two separate occasions called 1994 JR1, which measures 145 kilometers (90 miles) across. KBOs are remnants of the early Solar System, in the form of icy comets and asteroids, so studying them could reveal important clues about our beginnings.

These observations werent comparable with the Pluto flyby though, when New Horizons flew just a few tens of thousands of kilometers above the surface. Instead, New Horizons snapped the KBO from a distance of 111 million kilometers (69 million miles) in early April, following preliminary observations from more than twice as far away in November 2015.

But this post-Pluto science is important, because it helps New Horizons practice for a more ambitious mission in 2019. On January 1 of that year, mission scientists will send New Horizons flying past a KBO called 2014 MU69 closer than it came to Pluto, although the exact flyby distance is not known yet.

As for JR1, well, we did actually learn a bit from these views. First, scientists were able to pinpoint its location to within 1,000 kilometers (621miles), the most accurate for any small KBO. This allowed them to rule out a theory that JR1 might be a distant satellite of Pluto. They were also able to work out JR1s rotation speed, clocking it at one rotation every 5.4 Earth hours.

Above, an animation of JR1 moving from two of 20 observations made in April 2016. Top left is an internal camera reflection, which NASA calls “a kind of selfie.”NASA/JHUAPL/SwRI

Thats relatively fast for a KBO, said science team member John Spencer, from the Southwest Research Institute (SwRI) in Colorado, in a statement. This is all part of the excitement of exploring new places and seeing things never seen before.

Before New Horizons reaches 2014 MU69, it willstudy about 20 more KBOs, pending approval for this extended mission from NASA (which seems a done deal at the moment). Pluto may have been impressive, but these endeavors will tell us even more about the outer Solar System than ever before.

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Read more: http://www.iflscience.com/new-horizons-begins-life-after-pluto

Comet To Make Close Approach To Mars

Spacecrafts from many countries will get a rare opportunity to study a comet as it hurtles past Mars on Sunday, October 19. For any comet to come so close to a planet is unusual, but the comet’s history should make this encounter particularly interesting. Amateur astronomers may also be able to join in as the comet is visible with moderate-sized telescopes.

Comet Siding Spring was reported by Rob McNaught last year. Having found 82 comets, more than any other person in history, and having the brightest comet of recent years named after him, McNaught credited this discovery to the observatory where the observations were made.

When McNaught discovered Comet Siding Spring, or C/2013 A1 as it was originally known, its orbit was calculated as taking it so close to Mars that it was considered possible it might collide. It took more than a year before this was ruled out, with an estimated clearance of 139,500 kilometers (87,000 miles)—less than half the distance between the Earth and our moon.

The paths of the missions orbiting Mars have been adjusted, where necessary, to ensure they are far enough away to be safe, not only from the comet itself but from the trail of debris it will leave behind. Meanwhile, NASA’s Mars orbiters will keep a close eye on the comet and the influence its tail has on the Martian atmosphere

Comets are divided into two categories, short and long-period comets. Long-period comets have spent most of their existence in the Oort Cloud, at distances where the sun appears as little more than a bright star. Consequently, they are time capsules of the early solar system. Short-period comets, on the other hand, have become trapped in the inner or middle solar system and pass close enough to the sun to lose their outer layers regularly, gradually shrinking away to nothing but grains of dust.

Comet Siding Spring doesn’t appear to be a particularly large comet, but as an intruder from the Oort Cloud on its first pass close to the sun, it provides a contrast to the short-period comets to which we have sent spacecraft.

“This is a cosmic science gift that could potentially keep on giving, and the agency’s diverse science missions will be in full receive mode,” says NASA’s John Grunsfeld. “This particular comet has never before entered the inner solar system, so it will provide a fresh source of clues to our solar system’s earliest days.” 



This will be the second time we have had a good view of the interaction of a comet and a planet after Shoemaker-Levy 9’s spectacular collision with Jupiter in 1994

The comet may be among McNaught’s last, with the Australian government refusing to match NASA funding to keep his program going.

Read more: http://www.iflscience.com/space/comet-make-close-approach-mars

The More We Learn About Mercury, The Weirder It Seems

For such a tiny planet, Mercury is a pretty big puzzle for researchers. NASAs MESSENGER probe already has revealed that the planet is surprisingly rich in elements that easily evaporate from the surface, such as sulphur, chlorine, sodium and potassium. This is incredibly odd as these kind of substances most likely would disappear during a hot or violent birth exactly the type of birth a planet so close to the sun, such as Mercury, would have had.

Scientists are also struggling to understand why Mercury is so dark and what its earliest planetary crust, created as the newly-formed planet cooled down, was made of. Research has now started to throw up answers but these are raising a lot of new questions.

In search of the oldest crust

Look at the moon and youll see dark lava flows that have been erupted over the brighter-looking terrain of the lunar highlands. The highlands are the moons oldest crust and were formed from a pile up of crystals called anorthite, which rose to the top of the global magma ocean that covered the moon in the aftermath of its violent birth.

Part of the Moon, with dark lava flows overlying bright (high albedo) primary crust. NASA/GSFC/Arizona State University/Quickmap

But if you look at Mercury as seen during during MESSENGERs 2011-2015 orbital campaign youll see no such thing. Mercury is dark everywhere. Its crust is mostly a series of giant lava sheets and the older ones have been around long enough to be scarred by a large number of impact craters created by comets and asteroids bombarding the surface.

2000 km wide area of Mercury. Unlike the Moon, it is all dark. NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/Quickmap

All those lava sheets must have been erupted on top of something so where is Mercurys oldest crust, and what was it made of? This is a problem that Mercury scientists have been grappling with since MESSENGER made its first flyby in 2008. They identified some particularly dark patches, dubbed low reflectance material, which apparently have been dug up to the surface as comets and asteroids hit it. But they could not work out what makes this material so dark, especially as MESSENGER proved that Mercurys surface is remarkably poor in iron, which could have darkened it.

However, it turns out that a lack of iron would make Mercurys original magma ocean less dense than the moons, so that any anorthite crystals that grew would sink rather than floating upwards to produce bright spots. In fact, the only mineral likely to crystallise that would have been able to float is graphite, the soft, dark form of carbon used in pencil lead.

Weird composition

A graphite crust on Mercury used to seem unlikely, especially if you assume that its carbon content is similar to that of the Earth or Mars. But now research suggests that this crust was indeed made largely out of graphite. That is strange because the other rocky planets have a lot less carbon on their surfaces, and carbonaceous asteroids from which a carbon-rich planet could form are much further from the sun than Mercurys present orbit.

The study analysed data collected by MESSENGER when the spacecraft was within 100 km of the surface. It showed that while the dark patches did contain graphite, it was far from being pure more like ordinary rock debris with a few percent of graphite mixed into it.

The 500 km wide Tolstoj basin, centre right, that exposes a dark ring of low reflectance material. The 75 km crater Basho, lower left, whose innermost ejecta is also low reflectance material. NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

So, we still have not found any of Mercurys primary crust exposed at the surface in an intact state, though we may have found the next best thing: the impact-pummelled surface of the original crust, dug out by later impacts. The original crust was overprinted by successive episodes of volcanism. There are also clear traces of much more recent hollows where the surface has been eaten away by some process that removed solid volatile substances such as sulfur, chlorine, sodium and potassium as vapour.

280 km wide view with an explosive volcanic vent just to the right of centre. The vent is surrounded by a pale, yellowish deposit that was erupted from it. NASA/JHUAPL/Carnegie Institute Washington

Most hollows are on or close to patches of low-reflectance material, so the primary crust itself could have been rich in these unlikely volatiles originally.

Scarlatti crater on Mercury. This exposes low reflectance material to the south of its peak-ring. The inset on the right, an area less than 5 km across, shows hollows forming there. NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

MESSENGER returned enough data to keep scientists busy for years to come, but to learn more about the crust and to work out exactly why the planet is so rich in strange elements we will probably have to await the arrival of the European Space Agencys BepColombo mission to Mercury in 2024.

Meanwhile, people across most of the globe will have an excellent chance to see Mercury for themselves when it crosses the face of the Sun (a solar transit) on 9 May 2016.

Read more: http://www.iflscience.com/space/more-we-learn-about-mercury-weirder-it-seems

Discovery Of Carbon On Mercury Reveals The Planets Dark Past

Mercury has been found to have a dark side with graphite, a crystalline form of carbon commonly found in pencils, being the source of the mysterious dark colouration of the planets surface.

The study, published this week in Nature Geoscience, was led by a team from the Johns Hopkins University Applied Physics Laboratory in the US, which analysed measurements collected by NASAs Messenger spacecraft as it went through its final orbits of Mercury.

The findings not only test theories of early planetary formation but may offer an explanation of the amount of carbon here on Earth.

Remains Of A Primordial Crust

The surface colour of planetary bodies is often an indicator of the elements that make them up. For example, the distinctive rusty red appearance of Mars can be attributed to iron oxide.

It had previously been believed that the iron and titanium were typically responsible for the dark coloration on planetary surfaces. However, Mercury is quite dark, but lacked high enough concentrations of those elements to account for its colour.

Mercurys surface was significantly darker than we could account for on the basis of our understanding of Mercurys surface chemistry, said Dr Patrick Peplowski, from the Johns Hopkins University Applied Physics Laboratory, and lead author on the study.

So what was causing Mercury to be so dark?

By carefully examining data sent back to Earth by the Messenger probe, the team found that the dark colouration was due to the presence of carbon, with Mercury having high levels than any other planets or their moons.

The discovery of carbon on Mercury was an unexpected one, so much so that none of the instruments on Messenger were designed to detect the element. Instead, Peplowski and his colleagues had to use multiple instruments to identify the carbon.

Need For Continued Planetary Exploration

The discovery gives weight to a theory on how Mercury was formed. The carbon-rich material was detected underneath younger volcanic materials that make up Mercurys present day surface. This suggests that early Mercurys original carbon-rich crust may have been formed from graphite that floated to the top of a global magma ocean.

These primordial floating crusts provide a rare perspective on early planetary formation.

This is interesting because the original crusts of the other planets were destroyed long ago by processes like volcanic resurfacing, plate tectonics and erosion, Peplowski told The Conversation.

The carbon we see today may be the remains of that ancient, 4.5 billion-year-old crust.

However, there are still questions as to how the planetary crust was originally formed and why carbon was found around some craters and not others.

There is a lot of follow-on work to be done, said Peplowski. Future missions to Mercury might benefit from instrumentation specifically designed to map carbon in order to follow up on this result.

The next planetary exploration of Mercury could provide further answers, with the European Space Agency launching the BepiColumbo probe to Mercury next year.

It has an entirely new suite of instruments that can add to our understanding of carbon on Mercury.

Planetary Puzzles

Dr Helen Maynard-Casely, an Instrument Scientist from the Australian Nuclear Science and Technology Organisation, who was not involved in the study, said the study sheds light on some longstanding mysteries in planetary science.

She added that the theory they study suggests that how Mercury evolved shares many similarities to the early formation of the Moon.

The early crust of the Moon was made of lighter minerals. It is thought these were stripped off the Earth. In terms of planetary formation, these minerals are like froth on a coffee. Then, as the surface of the Moon has evolved, impacts and lava flows have brought the darker material onto the faces of the Moon, she said.

What theyre seeing is that this darker material on Mercury is the remnants of the early frothy material. Graphite is light compared to the other materials on Mercury. They suggest this rose to the top at the very beginning of the planets formation creating the first crust of Mercury as it was cooling down.

But throughout the life of Mercury in the solar system, repeated impacts had churned up the crust, leaving very little of the early surface intact.

Maynard-Casely says that the discovery came as a surprise and may change our view on the how the solar system was formed, and the current model of predicting the presence of carbon, including here on Earth.

Carbons been a very tricky element to pin down, even on Earth, and it is a puzzle to discover what has happened to our carbon. Theres a thought now that a lot of the carbon on Earth is trapped further down within the interior and that we are missing a lot of minerals. There is currently a bit of a worldwide hunt for these, she said.

The knowledge of carbons significance on Mercury would bring those questions back to the forefront and reinvigorate discussions.

Ivy Shih, Editor, The Conversation

Read more: http://www.iflscience.com/space/discovery-cacrbon-mercury-reveals-planet-s-dark-past

Kepler Telescope Back With New Exoplanet Discovery

A remarkable technological fix has revived the Kepler Space Telescope, and it is once again finding planets beyond our solar system. So far, it has yet to match the astonishing feats of its earlier mission, when hundreds of likely planets were announced at a time. Nevertheless, the announcement that the telescope has found its first new exoplanet since the wheels literally came off is cause for celebration.

Early discoveries of planets circling other stars were made using the Doppler “wobble method.” While this is still used today to find planets around relatively nearby stars, it is a slow process. 

Kepler, on the other hand, has detected 996 confirmed exoplanets, and 3,216 that have yet to be verified. It did so through exceptionally sensitive measurements of the light coming from 145,000 stars. When planets pass in front of these stars they dim slightly, and where this happens regularly enough, Kepler can determine the planet’s orbital period.

The wealth of data Kepler produced has allowed astronomers to calculate the frequency of planetary systems in the galaxy, as well as pick up some particularly exciting examples. However, two of the reaction wheels that kept the telescope pointing in the right direction in the absence of gravity failed, ending observations in 2013.

Most of the exoplanet announcements came after this, as the data took a while to process, but the original mission was over. This, however, was not the end of Kepler’s capacity. NASA put out a call for suggestions on how the disabled, but not destroyed, spacecraft could be put to use, and in November 2013 adopted the K2 proposal to shift its focus. K2 relies on the pressure of sunlight to create what astronomers are calling a “virtual reaction wheel.”

Credit: NASA. Kepler is bracing itself against the pressure of sunlight to remain stable enough to take useful observations.

Kepler is now only one-fifteenth as precise as its earliest incarnation, but that is still enough to make observations of asteroids and comets within our solar system, as well as to trace the decline of supernovae. Moreover, it was thought possible that this lower precision might still be enough to find planets around red dwarf stars, even if the main sequence stars on which Kepler initially focused were now out of reach.

And so it has been proven. Phoenix-like, Kepler is back, with NASA announcing the confirmation of a potential planet, HIP 116454b, located during a test run in February. HIP 116454b lies 180 light-years from Earth toward the constellation Pisces and is around 2.5 times the diameter of Earth. Its existence was confirmed by the Telescopio Nazionale Galileo in the Canary Islands.

“The Kepler mission showed us that planets larger in size than Earth and smaller than Neptune are common in the galaxy, yet they are absent in our solar system,” said NASA’s Steve Howell.  “K2 is uniquely positioned to dramatically refine our understanding of these alien worlds and further define the boundary between rocky worlds like Earth and ice giants like Neptune.”

The work has been accepted for publication in The Astrophysical Journal. Meanwhile, space scientists are working on expanding Kepler’s capacities, with a focus on nearby stars.

Read more: http://www.iflscience.com/space/kepler-back-new-exoplanet