Although Tethys and Janus both orbit Saturn and are both made of more or less the same materials, they are very different worlds. via NASA http://ift.tt/1RftqBR
Stars are forming in the Soul of the Queen of Aethopia. More specifically, a large star forming region called the Soul Nebula can be found in the direction of the constellation Cassiopeia, who Greek mythology credits as the vain wife of a King who long ago ruled lands surrounding the upper Nile river. The Soul Nebula houses several open clusters of stars, a large radio source known as W5, and huge evacuated bubbles formed by the winds of young massive stars. Located about 6,500 light years away, the Soul Nebula spans about 100 light years and is usually imaged next to its celestial neighbor the Heart Nebula (IC 1805). The featured image appears mostly red due to the emission of a specific color of light emitted by excited hydrogen gas. via NASA http://ift.tt/1Rcu039
Gaze across the frozen canyons of northern Pluto in this contrast enhanced color scene, imaged last July by the New Horizons spacecraft. Currently known as Lowell Regio, the region has been informally named for Percival Lowell, founder of the Lowell Observatory. Also famous for his speculation that there were canals on Mars, in 1906 Lowell started the search that ultimately led to Pluto's discovery. Pluto's North Pole itself is above and left of center in the the frame. The pale bluish floor of the broad canyon on the left is about 70 kilometers (45 miles) wide, running vertically toward the south. Higher elevations take on a yellowish hue. New Horizon's measurements have determined that in addition to nitrogen ice, methane ice is abundant across northern Pluto's Lowell Regio. via NASA http://ift.tt/1TFkkD3
The Tarantula Nebula is more than a thousand light-years in diameter, a giant star forming region within nearby satellite galaxy the Large Magellanic Cloud, about 180 thousand light-years away. The largest, most violent star forming region known in the whole Local Group of galaxies, the cosmic arachnid sprawls across this spectacular composite view constructed with space- and ground-based image data. Within the Tarantula (NGC 2070), intense radiation, stellar winds and supernova shocks from the central young cluster of massive stars, cataloged as R136, energize the nebular glow and shape the spidery filaments. Around the Tarantula are other star forming regions with young star clusters, filaments, and blown-out bubble-shaped clouds In fact, the frame includes the site of the closest supernova in modern times, SN 1987A, at the lower right. The rich field of view spans about 1 degree or 2 full moons, in the southern constellation Dorado. But were the Tarantula Nebula closer, say 1,500 light-years distant like the local star forming Orion Nebula, it would take up half the sky. via NASA http://ift.tt/1XPFyyp
The distinctive blue bubble appearing to encircle WR 31a is a Wolf–Rayet nebula — an interstellar cloud of dust, hydrogen, helium and other gases. Created when speedy stellar winds interact with the outer layers of hydrogen ejected by Wolf–Rayet stars, these nebulae are frequently ring-shaped or spherical. via NASA http://ift.tt/1oEvGez
Fans of planet Earth probably recognize its highest mountain, the Himalayan Mount Everest, on the left in this 3-panel skyscape of The World at Night. Shrouded in cloud Everest's peak is at 8,848 meters (29,029 feet) elevation above sea level. In the middle panel, stars trail above volcanic Mauna Kea forming part of the island of Hawaii. Festooned with astronomical observatories, its summit lies a mere 4,168 meters above sea level. Still, measured from its base starting below the ocean's surface, Mauna Kea is over 10,000 meters tall, making it Earth's tallest mountain from base to summit. At right, beneath the arc of the Milky Way is the Andean mountain Chimborazo in Ecuador. The highest equatorial mountain, the Chimborazo volcano's peak elevation is 6,268 meters above sea level. But rotating planet Earth is a flattened sphere (oblate spheroid) in shape, its equatorial diameter greater than its diameter measured pole to pole. Sitting nearly on top of Earth's greatest equatorial bulge, Chimborazo's peak is the farthest point on the planet's surface from the center, over 2,000 meters farther from the center of the Earth than Everest's peak. That makes Chimborazo's summit the place on Earth's surface closest to the stars. via NASA http://ift.tt/1XOFjnl
NASA research mathematician Katherine Johnson is photographed at her desk at Langley Research Center in 1966. Johnson made critical technical contributions during her career of 33 years, which included calculating the trajectory of the 1961 flight of Alan Shepard. She was awarded the Presidential Medal of Freedom on Nov. 24, 2015. via NASA http://ift.tt/1QgSqsn
Can you identify a familiar area in the northeast USA just from nighttime lights? It might be possible because many major cities are visible, including (right to left) New York, Philadelphia, Baltimore, Washington, Richmond and Norfolk -- Boston of the USA's Northeast megalopolis is not pictured. The featured image was taken in 2012 from the International Space Station. In the foreground are two Russian cargo ships with prominent solar panels. This Northeast megalopolis of the USA contains almost 20 percent of the people of the USA but only about 2 percent of the land area. Also known also as the Northeast Corridor and part of the Eastern Seaboard, about 10 percent of the world's largest companies are headquartered here. The near continuity of the lights seem to add credence to the 1960s-era prediction that the entire stretch is evolving into one continuous city. via NASA http://ift.tt/1QxN7Ei
Expedition 46 crew member Tim Peake of the European Space Agency (ESA) shared a stunning image of a glowing aurora taken on Feb. 23, 2016, from the International Space Station. Peake wrote, "The @Space_Station just passed straight through a thick green fog of #aurora…eerie but very beautiful. #Principia" via NASA http://ift.tt/1Qyiuyk
Telescopes around the world are tracking a bright supernova that occurred in a nearby dusty galaxy. The powerful stellar explosion was first noted earlier this month. The nearby galaxy is the photogenic Centaurus A, visible with binoculars and known for impressive filaments of light-absorbing dust that cross its center. Cen A is featured here in a high-resolution archival Hubble Space Telescope image, with an inset image featuring the supernova taken from the ground only two days after discovery. Designated SN2016adj, the supernova is highlighted with crosshairs in the inset, appearing just to the left of a bright foreground star in our Milky Way Galaxy. This supernova is currently thought to be of Type IIb, a stellar-core-collapse supernova, and is of high interest because it occurred so nearby and because it is being seen through a known dust filament. Current and future observations of this supernova may give us new clues about the fates of massive stars and how some elements found on our Earth were formed. via NASA http://ift.tt/1Q8JuoZ
This image, acquired by the Operational Land Imager (OLI) on Landsat 8, shows the glaciers of Sierra de Sangra on Jan. 14, 2015. Snow and ice are blue in these false-color images, which use different wavelengths to better differentiate areas of ice, rock, and vegetation. via NASA http://ift.tt/1T4g2qg
What's lighting up the Cigar Galaxy? M82, as this irregular galaxy is also known, was stirred up by a recent pass near large spiral galaxy M81. This doesn't fully explain the source of the red-glowing outwardly expanding gas, however. Evidence indicates that this gas is being driven out by the combined emerging particle winds of many stars, together creating a galactic superwind. The featured photographic mosaic highlights a specific color of red light strongly emitted by ionized hydrogen gas, showing detailed filaments of this gas. The filaments extend for over 10,000 light years. The 12-million light-year distant Cigar Galaxy is the brightest galaxy in the sky in infrared light, and can be seen in visible light with a small telescope towards the constellation of the Great Bear (Ursa Major). via NASA http://ift.tt/20NADOn
Want to take a relaxing interstellar vacation? Consider visiting Kepler-16b, a world in a binary star system. In fact Kepler-16b is the first discovered circumbinary planet. It was detected in a wide 229 day orbit around a close pair of cool, low-mass stars some 200 light-years away. The parent stars eclipse one another in their orbits, observed as a dimming of starlight. But Kepler-16b itself was discovered by following the additional very slight dimming produced during its transits. Like sci-fi planet Tatooine of Star Wars fame, two suns would set over its horizon. Still, Kepler 16b is probably not a Tatooine-like terrestrial desert world. Instead, Kepler 16b is thought to be a cold, uninhabitable planet with about the mass of Saturn and a gaseous surface ... so plan to dress accordingly. Or, choose another Visions of the Future vacation destination. via NASA http://ift.tt/1TwmINu
Magnificent island universe NGC 2403 stands within the boundaries of the long-necked constellation Camelopardalis. Some 10 million light-years distant and about 50,000 light-years across, the spiral galaxy also seems to have more than its fair share of giant star forming HII regions, marked by the telltale reddish glow of atomic hydrogen gas. The giant HII regions are energized by clusters of hot, massive stars that explode as bright supernovae at the end of their short and furious lives. A member of the M81 group of galaxies, NGC 2403 closely resembles another galaxy with an abundance of star forming regions that lies within our own local galaxy group, M33 the Triangulum Galaxy. Spiky in appearance, bright stars in this colorful galaxy portrait of NGC 2403 are in the foreground, within our own Milky Way. via NASA http://ift.tt/1PWr22G
This image, acquired on Nov. 24, 2015 by the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter, shows the western side of an elongated pit depression in the eastern Noctis Labyrinthus region of Mars. Along the pit's upper wall is a light-toned layered deposit. via NASA http://ift.tt/1VsgGvb
On February 17 at 5:45pm JST this H-IIA rocket blasted skyward from JAXA's Tanegashima Space Center located off the southern coast of Japan, planet Earth. Onboard was the ASTRO-H X-ray astronomy satellite, now in orbit. Designed to explore the extreme cosmos from black holes to massive galaxy clusters, the satellite observatory is equipped with four cutting-edge X-ray telescopes and instruments sensitive to photon energies from 300 to 600,000 electron volts. By comparison, visible light photon energies are 2 to 3 electron volts. Following a tradition of renaming satellites after their successful launch, ASTRO-H has been newly dubbed "Hitomi", inspired by an ancient legend of dragons. Hitomi means "the pupil of the eye". via NASA http://ift.tt/1Qo1pqI
On Sept. 12, 1992, launch day of the STS-47 Spacelab-J mission on space shuttle Endeavour, NASA astronaut Mae Jemison waits as her suit technician, Sharon McDougle, performs a unpressurized and pressurized leak check on her spacesuit at the O&C Building at Kennedy Space Center. Dr. Jemison was the first African-American woman to fly in space. via NASA http://ift.tt/1UawQLh
What strange world is this? Earth. In the foreground of the featured image are the Pinnacles, unusual rock spires in Nambung National Park in Western Australia. Made of ancient sea shells (limestone), how these human-sized picturesque spires formed remains unknown. In the background, just past the end of the central Pinnacle, is a bright crescent Moon. The eerie glow around the Moon is mostly zodiacal light, sunlight reflected by dust grains orbiting between the planets in the Solar System. Arching across the top is the central band of our Milky Way Galaxy. Many famous stars and nebula are also visible in the background night sky. The featured 29-panel panorama was taken and composed last September after detailed planning that involved the Moon, the rock spires, and their corresponding shadows. Even so, the strong zodiacal light was a pleasant surprise. via NASA http://ift.tt/1Sy9BuV
Engineers from NASA’s Langley Research Center and Boeing dropped a full-scale test article of the company’s CST-100 Starliner into Langley’s 20-foot-deep Hydro Impact Basin. Although the spacecraft is designed to land on land, Boeing is testing the Starliner’s systems in water to ensure astronaut safety in the unlikely event of an emergency. via NASA http://ift.tt/218F5cG
Massive star IRS 4 is beginning to spread its wings. Born only about 100,000 years ago, material streaming out from this newborn star has formed the nebula dubbed Sharpless 2-106 Nebula (S106), featured here. A large disk of dust and gas orbiting Infrared Source 4 (IRS 4), visible in brown near the image center, gives the nebula an hourglass or butterfly shape. S106 gas near IRS 4 acts as an emission nebula as it emits light after being ionized, while dust far from IRS 4 reflects light from the central star and so acts as a reflection nebula. Detailed inspection of a recent infrared image of S106 reveal hundreds of low-mass brown dwarf stars lurking in the nebula's gas. S106 spans about 2 light-years and lies about 2000 light-years away toward the constellation of the Swan (Cygnus). via NASA http://ift.tt/1VjGAB9
Zinnia plants from the Veggie ground control experiment at NASA’s Kennedy Space Center in Florida were harvested Feb. 11 in the same way that crew member Scott Kelly will harvest the zinnias growing in the Veggie system aboard the International Space Station on Feb. 14—Valentine’s Day. via NASA http://ift.tt/247LgjK
What caused this unusual light rock formation on Mars? Intrigued by the possibility that they could be salt deposits left over as an ancient lakebed dried-up, detailed studies of these fingers now indicate a more mundane possibility: volcanic ash. Studying the exact color of the formation indicated the possible volcanic origin. The light material appears to have eroded away from surrounding area, indicating a very low-density substance. The stark contrast between the rocks and the surrounding sand is compounded by the unusual darkness of the sand. The featured picture was taken with the Thermal Emission Imaging System on the Mars Odyssey, the longest serving spacecraft currently orbiting Mars. The image spans about 10 kilometers inside a larger crater. via NASA http://ift.tt/1KRtuuD
Can a cloud love a mountain? Perhaps not, but on a Valentine's Day like today, one might be prone to seeing heart-shaped symbols where they don't actually exist. A fleeting pareidolia, the featured heart was really a lenticular cloud that appeared one morning last July above Mount Cook National Park in New Zealand. A companion video shows the lenticular cloud was mostly stationary in the sky but shifted and vibrated with surrounding winds. The cloud's red color was caused by the Sun rising off the frame to the right. Lenticular clouds are somewhat rare but can form in air that passes over a mountain. Then, vertical eddies may form where rising air cools past the dew point causing water carried by the air to condense into droplets. Unfortunately, this amazing sight made the fascinated videographer late for breakfast. via NASA http://ift.tt/1og4vHA
Tracks lead to a small robot perched near the top of this bright little planet. Of course, the planet is really the Moon. The robot is the desk-sized Yutu rover, leaving its looming Chang'e 3 lander after a after a mid-December 2013 touch down in the northern Mare Imbrium. The little planet projection is a digitally warped and stitched mosaic of images from the lander's terrain camera covering 360 by 180 degrees. Ultimately traveling over 100 meters, Yutu came to a halt in January 2014. The lander's instruments are still working though, after more than two years on the lunar surface. Meanwhile, an interactive panoramic version of this little planet is available here. via NASA http://ift.tt/2112D33
Gravitational radiation has been directly detected. The first-ever detection was made by both facilities of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana simultaneously last September. After numerous consistency checks, the resulting 5-sigma discovery was published today. The measured gravitational waves match those expected from two large black holes merging after a death spiral in a distant galaxy, with the resulting new black hole momentarily vibrating in a rapid ringdown. A phenomenon predicted by Einstein, the historic discovery confirms a cornerstone of humanity's understanding of gravity and basic physics. It is also the most direct detection of black holes ever. The featured illustration depicts the two merging black holes with the signal strength of the two detectors over 0.3 seconds superimposed across the bottom. Expected future detections by Advanced LIGO and other gravitational wave detectors may not only confirm the spectacular nature of this measurement but hold tremendous promise of giving humanity a new way to see and explore our universe. via NASA http://ift.tt/20Xw6La
NASA astronaut Peggy Whitson trains underwater for a spacewalk at the Neutral Buoyancy Laboratory (NBL) at Johnson Space Center in Houston. Whitson is scheduled to launch to the International Space Station in late 2016 as part of Expedition 50/51. via NASA http://ift.tt/1muWexu
Large galaxies grow by eating small ones. Even our own galaxy practices galactic cannibalism, absorbing small galaxies that get too close and are captured by the Milky Way's gravity. In fact, the practice is common in the universe and illustrated by this striking pair of interacting galaxies from the banks of the southern constellation Eridanus, The River. Located over 50 million light years away, the large, distorted spiral NGC 1532 is seen locked in a gravitational struggle with dwarf galaxy NGC 1531 (right of center), a struggle the smaller galaxy will eventually lose. Seen edge-on, spiral NGC 1532 spans about 100,000 light-years. Nicely detailed in this sharp image, the NGC 1532/1531 pair is thought to be similar to the well-studied system of face-on spiral and small companion known as M51. via NASA http://ift.tt/1QVr7Gd
The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Aqua satellite captured this image of cloud streets and sea ice in the Sea of Okhotsk on Feb. 8, 2016. Cloud streets are long parallel bands of cumulus clouds that form when cold air blows over warmer waters and a warmer air layer rests over the top of both. via NASA http://ift.tt/1osc2Tu
STS-63 astronauts Bernard A. Harris, Jr., payload commander (right), and C. Michael Foale, mission specialist (left), are ready to exit space shuttle Discovery's airlock for a spacewalk on Feb. 9, 1995. On this extravehicular activity (EVA), which lasted 4 hours and 38 minutes, Bernard Harris became the first African-American to walk in space. via NASA http://ift.tt/20TmLnI
What's happening behind those houses? Pictured here are not auroras but nearby light pillars, a nearby phenomenon that can appear as a distant one. In most places on Earth, a lucky viewer can see a Sun-pillar, a column of light appearing to extend up from the Sun caused by flat fluttering ice-crystals reflecting sunlight from the upper atmosphere. Usually these ice crystals evaporate before reaching the ground. During freezing temperatures, however, flat fluttering ice crystals may form near the ground in a form of light snow, sometimes known as a crystal fog. These ice crystals may then reflect ground lights in columns not unlike a Sun-pillar. The featured image was taken in Fort Wainwright near Fairbanks in central Alaska. via NASA http://ift.tt/1nSIfTe
On the evening of Feb. 7, 2016, Expedition 46 Commander Scott Kelly snapped this photo of Levi's Stadium in Santa Clara, Calif. from the International Space Station, writing, "Got to see the #SuperBowl in person after all! But at 17,500MPH, it didn't last long. #YearInSpace" via NASA http://ift.tt/20Rhu07
Accelerate a charge and you'll get electromagnetic radiation: light. But accelerate any mass and you'll get gravitational radiation. Light is seen all the time, but, so far, a confirmed direct detection of gravitational radiation has been elusive. When absorbed, gravitational waves create a tiny symmetric jiggle similar to squashing a rubber ball and letting go quickly. Separated detectors can be used to discern gravitational waves from everyday bumps. Powerful astronomical sources of gravitational radiation would coincidentally jiggle even detectors on opposite ends of the Earth. Pictured here are the four-kilometer-long arms of one such detector: the LIGO Hanford Observatory in Washington state, USA. Together with its sister interferometer in Louisiana, these gravitational wave detectors continue to be upgraded and are now more sensitive than ever. via NASA http://ift.tt/1W2fAWX
February's five planet line-up stretches across a clear sky in this predawn scene. A hilltop Castell de Burriac looms in the foreground, overlooking the town of Cabrera de Mar near Barcelona, Spain, planet Earth. The mosaicked, panoramic image looks south. It merges three different exposure times to record a bright Last Quarter Moon, planets, seaside city lights, and dark castle ruins. Seen on February 1st the Moon was near Mars on the sky. But this week early morning risers have watched it move on, passing near Saturn and finally Venus and Mercury, sliding along near the ecliptic toward the dawn, approaching the February 7 New Moon. via NASA http://ift.tt/1PZChqj
Massive stars lie within NGC 6357, an expansive emission nebula complex some 6,500 light-years away toward the tail of the constellation Scorpius. In fact, positioned near center in this ground-based close-up of NGC 6357, star cluster Pismis 24 includes some of the most massive stars known in the galaxy, stars with nearly 100 times the mass of the Sun. The nebula's bright central region also contains dusty pillars of molecular gas, likely hiding massive protostars from the prying eyes of optical instruments. Intricate shapes in the nebula are carved as interstellar winds and energetic radiation from the young and newly forming massive stars clear out the natal gas and dust and power the nebular glow. Enhancing the nebula's cavernous appearance, narrowband image data was included in this composite color image in a Hubble palette scheme. Emission from sulfur, hydrogen, and oxygen atoms is shown in red green and blue hues. The alluring telescopic view spans about 50 light-years at the estimated distance of NGC 6357. via NASA http://ift.tt/1R9z4d3
Dwarf planet Ceres is the largest object in the Solar System's main asteroid belt, with a diameter of about 950 kilometers (590 miles). Ceres is seen here in approximately true color, based on image data from the Dawn spacecraft recorded on May 4, 2015. On that date, Dawn's orbit stood 13,642 kilometers above the surface of the small world. Two of Ceres' famous mysterious bright spots at Oxo crater and Haulani crater are near center and center right of this view. Casting a telltale shadow at the bottom is Ceres' cone-shaped, lonely mountain Ahuna Mons. Presently some 385 kilometers above the Cerean surface, the ion-propelled Dawn spacecraft is now returning images from its closest mapping orbit. via NASA http://ift.tt/20t6SaU
The nitrogen ice glaciers on Pluto appear to carry an intriguing cargo: numerous, isolated hills that may be fragments of water ice from Pluto’s surrounding uplands. These hills individually measure one to several miles or kilometers across, according to images and data from NASA’s New Horizons mission. via NASA http://ift.tt/1nPILSw
In the lower left corner, surrounded by blue spiral arms, is spiral galaxy M81. In the upper right corner, marked by red gas and dust clouds, is irregular galaxy M82. This stunning vista shows these two mammoth galaxies locked in gravitational combat, as they have been for the past billion years. The gravity from each galaxy dramatically affects the other during each hundred million-year pass. Last go-round, M82's gravity likely raised density waves rippling around M81, resulting in the richness of M81's spiral arms. But M81 left M82 with violent star forming regions and colliding gas clouds so energetic the galaxy glows in X-rays. This big battle is seen from Earth through the faint glow of an Integrated Flux Nebula, a little studied complex of diffuse gas and dust clouds in our Milky Way Galaxy. In a few billion years only one galaxy will remain. via NASA http://ift.tt/1TDhw9I
In this Feb. 3, 1995, image taken onboard space shuttle Discovery on flight day one of the STS-63 mission, astronaut Eileen M. Collins -- the first woman to pilot the shuttle -- is at the pilot's station during a "hotfiring" procedure prior to rendezvous with the Russian Mir Space Station. via NASA http://ift.tt/1o6BSMq
Spacecraft Rosetta continues to circle and map Comet Churyumov-Gerasimenko. Crossing the inner Solar System for ten years to reach the vicinity of the comet in 2014, the robotic spacecraft continues to image the unusual double-lobed comet nucleus. The featured image, taken one year ago, shows dust and gas escaping from the comet's nucleus. Although appearing bright here, the comet's surface reflects only about four percent of impinging visible light, making it as dark as coal. Comet 67P/Churyumov–Gerasimenko spans about four kilometers in length and has a surface gravity so low that an astronaut could jump off of it. With Rosetta in tow, Comet 67P passed its closest to the Sun last year and is now headed back to the furthest point -- just past the orbit of Jupiter. via NASA http://ift.tt/1RXUbjl
Expedition 46 flight engineer Tim Peake of ESA captured this photo on Jan. 29, 2016 from the International Space Station, as the robotic arm in Japan's Kibo laboratory successfully deployed two combined satellites: AggieSat4 built by Texas A&M University students, and BEVO-2 built by University of Texas students. via NASA http://ift.tt/1PdBVNe
Have you ever seen the Man on the Moon? This common question plays on the ability of humans to see pareidolia -- imagining familiar icons where they don't actually exist. The textured surface of Earth's full Moon is home to numerous identifications of iconic objects, not only in modern western culture but in world folklore throughout history. Examples, typically dependent on the Moon's perceived orientation, include the Woman in the Moon and the Rabbit in the Moon. One facial outline commonly identified as the Man in the Moon starts by imagining the two dark circular areas -- lunar maria -- here just above the Moon's center, to be the eyes. Surprisingly, there actually is a man in this Moon image -- a close look will reveal a real person -- with a telescope -- silhouetted against the Moon. This featured well-planned image was taken in mid-January in Cadalso de los Vidrios in Madrid, Spain. Do you have a favorite object that you see in the Moon? via NASA http://ift.tt/1QBUFZn
NASA's Super Guppy aircraft readies to transport an Orion spacecraft from the Michoud Assembly Facility in Louisiana to Kennedy Space Center in Florida. via NASA http://ift.tt/1P9X4be
A team of astronomers in the UK, USA and Australia have found a lonely planet, until now thought to be a free floating or lonely planet, in a huge orbit around its star. Incredibly the object, designated as 2MASS J2126, is about 1 trillion (1 million million) kilometres from the star, or about 7000 times the distance from the Earth to the Sun. The researchers report the discovery in a paper in Monthly Notices of the Royal Astronomical Society.
In the last five years a number of free floating planets have been found. These are gas giant worlds like Jupiter that lack the mass for the nuclear reactions that make stars shine, so cool and fade over time. Measuring the temperatures of these objects is relatively straightforward, but it depends on both mass and age. This means astronomers need to find out how old they are, before they can find out if they are lightweight enough to be planets or if they are heavier 'failed stars' known as brown dwarfs.
US-based researchers found 2MASS J2126 in an infrared sky survey, flagging it as a possible young and hence low mass object. In 2014 Canadian researchers identified 2MASS J2126 as a possible member of a 45 million year old group of stars and brown dwarfs known as the Tucana Horologium Association. This made it young and low enough in mass to be classified as a free-floating planet.
In the same region of the sky, TYC 9486-927-1 is a star that had been identified as being young, but not as a member of any known group of young stars. Until now no one had suggested that TYC 9486-927-1 and 2MASS J2126 were in some way linked.
Lead author Dr Niall Deacon of the University of Hertfordshire has spent the last few years searching for young stars with companions in wide orbits. As part of the work, his team looked through lists of known young stars, brown dwarfs and free-floating planets to see if any of them could be related. They found that TYC 9486-927-1 and 2MASS J2126 are moving through space together and are both about 104 light years from the Sun, implying that they are associated.
"This is the widest planet system found so far and both the members of it have been known for eight years," said Dr Deacon, "but nobody had made the link between the objects before. The planet is not quite as lonely as we first thought, but it's certainly in a very long distance relationship."
When they looked in more detail, the team were not able to confirm that TYC 9486-927-1 and 2MASS J2126 are members of any known group of young stars.
"Membership in a group of young stars is great for establishing an age," said study co-author Josh Schlieder of the NASA Ames Research Center, "but when we can't use that we need to resort to other methods."
The team then looked at the spectrum – the dispersed light – of the star to measure the strength of a feature caused by the element lithium. This is destroyed early on in a star's life so the more lithium it has, the younger it is. TYC 9486-927-1 has stronger signatures of lithium than a group of 45 million year old stars (the Tucana Horologium Association) but weaker signatures than a group of 10 million year old stars, implying an age between the two.
Based on this age the team was able to estimate the mass of 2MASS J2126, finding it to be between 11.6 to 15 times the mass of Jupiter. This placed it on the boundary between planets and brown dwarfs. It means that 2MASS J2126 has a similar mass, age and temperature to one of the first planets directly imaged around another star, beta Pictoris b.
"Compared to beta Pictoris b, 2MASS J2126 is more than 700 times further away from its host star," Dr Simon Murphy of the Australian National University, also a study co-author, "but how such a wide planetary system forms and survives remains an open question."
2MASS J2126 is around 7000 Earth-Sun distances or 1 trillion kilometres away from its parent star, giving it the widest orbit of any planet found around another star. At such an enormous distance it takes roughly 900,000 years to complete one orbit, meaning it has completed less than fifty orbits over its lifetime. There is little prospect of any life on an exotic world like this, but any inhabitants would see their 'Sun' as no more than a bright star, and might not even imagine they were connected to it at all.
What could cause a nebula to appear square? No one is quite sure. The hot star system known as MWC 922, however, appears to be embedded in a nebula with just such a shape. The featured image combines infrared exposures from the Hale Telescope on Mt. Palomar in California, and the Keck-2 Telescope on Mauna Kea in Hawaii. A leading progenitor hypothesis for the square nebula is that the central star or stars somehow expelled cones of gas during a late developmental stage. For MWC 922, these cones happen to incorporate nearly right angles and be visible from the sides. Supporting evidence for the cone hypothesis includes radial spokes in the image that might run along the cone walls. Researchers speculate that the cones viewed from another angle would appear similar to the gigantic rings of supernova 1987A, possibly indicating that a star in MWC 922 might one day itself explode in a similar supernova. via NASA http://ift.tt/1TuXUo7