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Infrared emission from methane suggests atmospheric heating by auroral processes. Astronomers using NASA’s James Webb Space Telescope have found a brown dwarf (an object more massive than Jupiter but smaller than a star) with infrared emission from methane, likely due to energy in its upper atmosphere. This is an unexpected discovery because the brown dwarf, W1935, is cold and lacks a host star; therefore, there is no obvious source for the upper atmosphere energy. The team speculates that the methane emission may be due to processes generating aurorae. These findings are being presented at the 243rd meeting of the American...

The galactic plane, seen through infrared eyes. (NASA/JPL-Caltech/UCLA) ______________________________________________________________________________________ There are many kinds of stars out there in the big, wide Universe. We have a whole system for categorizing them according to temperature, size, and brightness. Even so, a recently discovered object is suggesting that we're far from knowing everything. It's been nicknamed 'The Accident', and it's a type of object called a brown dwarf, also known as failed stars. But it's unlike any brown dwarf we've ever seen before, with a confusing spectrum – suggesting that it may be nearly as old as the Universe. Since all of the...

Brown dwarfs such as “The Accident” are illuminating the murky borderlands that separate planets from stars. Dan Caselden was up late on November 3, 2018, playing the video game Counter-Strike, when he made astronomy history. Every time he died, he would jump on his laptop to check in on an automated search he was running of NASA space telescope images. Suddenly, in the early hours of the morning, something bizarre popped into view. “It was very confusing,” said Caselden. “It was moving faster than anything I’ve discovered. It was faint and fast, which made it very weird.” Caselden emailed the...

Scientists have spotted one of the largest stellar flares ever recorded in our galaxy. The jets of plasma shot outward from the sun's nearest neighbor, the red dwarf star Proxima Centauri. The flare, which was around 100 times more powerful than any experienced in our solar system, could change the way scientists think about solar radiation and alien life.Proxima Centauri is a red dwarf — the smallest, dimmest and most common type of main sequence stars in the galaxy — located approximately 4.25 light-years from Earth. Its mass is only one-eighth of the sun's, and it is orbited by two...

Artist’s impression of the cold brown dwarf BDR J1750+3809. The blue loops depict the magnetic field lines. Charged particles moving along these lines emit radio waves that LOFAR detected. Some particles eventually reach the poles and generate aurorae similar to the northern lights on Earth. Credit: ASTRON/Danielle Futselaar ========================================================================== Gemini North and IRTF Confirm LOFAR Discovery For the first time, astronomers have used observations from the LOFAR radio telescope, the NASA IRTF, operated by the University of Hawai‘i, and the international Gemini Observatory, a Program of NSF’s NOIRLab, to discover and characterize a cold brown dwarf. The object, designated BDR...

Astronomers using the National Science Foundation's Karl G. Jansky Very Large Array (VLA) have made the first radio-telescope detection of a planetary-mass object beyond our Solar System. The object, about a dozen times more massive than Jupiter, is a surprisingly strong magnetic powerhouse and a "rogue," traveling through space unaccompanied by any parent star. "This object is right at the boundary between a planet and a brown dwarf, or 'failed star,' and is giving us some surprises that can potentially help us understand magnetic processes on both stars and planets," said Melodie Kao, who led this study while a graduate...

LOS ANGELES (AP) - NASA's Spitzer Space Telescope has spotted a dusty disc of material around a very small "failed star" called a brown dwarf, raising the possibility that there may be miniature solar systems in which planets orbit objects not much larger than planets, scientists said Monday. The brown dwarf named OTS 44 is only about 15 times the mass of Jupiter, much smaller than any other brown dwarf known to be surrounded by a disc of planet-building material, said Kevin Luhman, lead author of a study by the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "The neat thing...

Astronomers using NASA's Hubble Space Telescope have photographed one of the smallest objects ever seen around a normal star beyond our Sun. Weighing in at 12 times the mass of Jupiter, the object is small enough to be a planet. The conundrum is that it's also large enough to be a brown dwarf, a failed star.

Scientists using NASA's Spitzer Space Telescope have discovered and directly imaged a small brown dwarf star, 50 times the mass of Jupiter... The discovery concerns a class of the coldest brown dwarfs, called T dwarfs... Luhman's team also discovered a second brown dwarf that is smaller yet, about 20 times the mass of Jupiter, orbiting another star... could be the youngest T dwarf known, offering scientists a snapshot of early brown-dwarf development. The two T dwarfs are the first to be imaged by Spitzer... Spitzer also discovered a T dwarf that is floating through space by itelf rather than orbiting...

Luhman and his colleagues used the Hubble Space Telescope to photograph an object, about 10 Jupiter masses, orbiting the star CHXR 73. The orbiting object's mass alone would typically identify it as a heavy planet spawned from a disk that once surrounded this young star. However, the newfound object lies about five times as far from CHXR 73 as Pluto's average distance from the sun. Theory suggests that a gas-and-dust disk isn't likely to contain enough material that far from a star to make a planet... Distinguishing between brown dwarfs and planets is important, says Luhman. A brown dwarf could...

A group of astronomers from the US, Europe, Chile and South Africa have determined that 70,000 years ago a recently discovered dim star is likely to have passed through the solar system's distant cloud of comets, the Oort Cloud. No other star is known to have ever approached our solar system this close - five times closer than the current closest star, Proxima Centauri. In a paper published in Astrophysical Journal Letters, lead author Eric Mamajek from the University of Rochester and his collaborators analyzed the velocity and trajectory of a low-mass star system nicknamed "Scholz's star." The star's trajectory...

Scholz's star -- named after the German astronomer who discovered it -- approached less than a light-year from the Sun. Nowadays it is almost 20 light-years away, but 70,000 years ago it entered the Oort cloud, a reservoir of trans-Neptunian objects located at the confines of the solar system. ... Now two astronomers from the Complutense University of Madrid, the brothers Carlos and Raúl de la Fuente Marcos, together with the researcher Sverre J. Aarseth of the University of Cambridge (United Kingdom), have analyzed for the first time the nearly 340 objects of the solar system with hyperbolic orbits (very...

It’s a big, dark presence at the farthest reaches of our solar system, a mysterious force powerful enough to skew the paths of planets in orbit and yet so subtle that it slips undetected past even the most powerful telescopes on Earth. For centuries, it has eluded some of the most brilliant minds in astronomy — some say it even destroyed one. It’s the subject of endless calculations and rampant speculation, crackpot theories and countless hours spent gazing, fruitlessly, at the night sky. It’s known as Planet X. And on Tuesday, a group of astronomers said they’d found not just...

Highlighted by astronomers at the University of Rochester and the European Southern Observatory, the star — nicknamed “Scholz’s star” — has a very low tangential velocity in the sky, but it has been clocked traveling at a breakneck speed away from us. In other words, from our perspective, Scholz’s star is fleeing the scene of a collision with us. “Most stars this nearby show much larger tangential motion,” said Eric Mamajek, of the University of Rochester. “The small tangential motion and proximity initially indicated that the star was most likely either moving towards a future close encounter with the solar...

A brown dwarf that’s as frosty as the Earth’s North Pole has been discovered lurking incredibly close to our Solar System. Astronomer Keven Luhman from Pennsylvania State University used NASA’s Wide-field Infrared Survey Explorer (WISE) and the Spitzer Space Telescope to pinpoint the object’s temperature and distance. This is the coldest brown dwarf found so far, and it’s a mere 7.2 light-years away, making it the seventh closest star-like object to the Sun. “It is very exciting to discover a new neighbor of our Solar System that is so close,” said Luhman in a press release. Brown dwarfs emerge when...

Odd orbits of remote objects hint at unseen world, new calculations suggest. An as yet undiscovered planet might be orbiting at the dark fringes of the solar system, according to new research.Too far out to be easily spotted by telescopes, the potential unseen planet appears to be making its presence felt by disturbing the orbits of so-called Kuiper belt objects, said Rodney Gomes, an astronomer at the National Observatory of Brazil in Rio de Janeiro. Kuiper belt objects are small icy bodies—including some dwarf planets—that lie beyond the orbit of Neptune. Once considered the ninth planet in our system, the...

Explanation: This cosmic snapshot composed with image data from NASA's Wide-field Infrared Survey Explorer (WISE) satellite captures a multitude of faint stars and distant galaxies toward the constellation Lyra at wavelengths longer than visible light. But the object circled at the center is not quite a star. Cataloged as WISE 1828+2650, it lies within 40 light-years of the Sun and is currently the coldest brown dwarf known. A brown dwarf begins like a star, with the gravitational collapse of a dense cloud of gas and dust, but is not massive enough to achieve the core temperatures and densities that trigger...

Long before the Bible's tale of Jonah being swallowed by a whale, a small wannabe star has emerged intact after being engulfed by a neighboring giant star, scientists say. The victim was a brown dwarf, a failed star too small to sustain the nuclear reactions that ignites regular stars. The purpetrator was a red giant, an ancient star that once resembled our Sun but which puffed up to enormous size after its hydrogen fuel was depleted. The red giant has since expelled most of its gas into space and transformed into a dense, Earth-sized star called a white dwarfs. Using...

LOS ANGELES – Astronomers peering through ground- and space-based telescopes have discovered what they believe is the birth of the smallest known solar system. Scientists found a tiny brown dwarf – or failed star – less than one hundredth the mass of the sun surrounded by what appears to be a disk of dust and gas. The brown dwarf – located 500 light years away in the constellation Chamaeleon – appears to be undergoing a planet-forming process that could one day yield a miniature solar system, said Kevin Luhman of Penn State University, who led the discovery. It's long believed...

Astronomers have directly observed an extrasolar planet for the first time, but are at a loss to explain what they see. More than 130 planets have been detected orbiting stars other than our own, the Sun. But because the stars far outshine the planets, all of the planets were detected indirectly - by how much they made their host stars wobble or dim, for example. Now, astronomers say they are almost certain they have snapped an actual image of an extrasolar planet. It was first seen at infrared wavelengths with the Very Large Telescope in Chile in April 2004, and...