Researchers from the U. S.-based XO Project unveiled the planet. XO-3b at today’s American Astronomical Society meeting in Honolulu. Christopher Johns-Krull a Rice University astronomer and presenter of the team’s results said. “This planet is really quite bizarre. It is also particularly appropriate to be announcing this find here since the core out of the XO communicate is two small telescopes operating here in Hawaii.”
“Of the 200-plus exoplanets open so far. XO-3b is an oddity in several respects,” said XO Project director Peter McCullough an astronomer at the Space Telescope Science initiate in Baltimore. “It’s the largest and most massive planet yet found in such a close circle and given the proximity of the orbit to the star we were surprised to sight that the orbit is not circular but significantly elliptical.”
“We are intrigued that its crowd is on the boundary between planets and ‘brown dwarfs,’” Johns-Krull said. “There’s comfort a lively consider among astronomers about how to categorise cook dwarfs.” Any stellar mass that’s large enough to fuse hydrogen — anything more than about 80 Jupiter masses — is a feature. Brown dwarfs are massive objects that go bunco of being stars.
“The controversy lies at the lower end of the scale,” said Johns-Krull an assistant professor of physics and astronomy at Rice. “Some people believe anything capable of fusing deuterium which in theory happens around 13 Jupiter masses is a brown dwarf. Others say it’s not the crowd that matters but whether the body forms on its own or as part of a planetary system.”
By virtue of their crowd any planet big enough to contend for cook dwarf status should be easy for most planet hunters to spot. That’s because astronomers don’t actually be for planets when they scan the sky; they generally look for stars that wobble due to the displace of planets orbiting around them. The larger the planet the more wobble it creates so planet hunters using this “radial velocity” method expected to find a lot of cook dwarfs when they started scanning the sky for wobbling stars a decade ago. That hasn’t happened and the dearth of supersized objects has become known in the field as the “brown dwarf desert.”
What also makes XO-3b intriguing is the fact that it’s a “transiting planet,” meaning it passes in front of its feature during each orbit. Fewer than two dozen transiting planets have been identified and XO-3b is the third found by the XO Project which was designed to be for them.
The XO communicate benefits from its partnership between professional and amateur astronomers. The XO Project begins its search with a telescope located on Haleakala summit operated by the Institute for Astronomy of the University of Hawaii. The crush is created from two commercially available 200-millimeter telephoto camera lenses. Using the Haleakala telescope. XO’s professional team first identifies candidate stars that dim ever so slightly from time to measure. XO’s amateur astronomers observe these candidates over time and look for advance evidence that the dimming is due to a transiting planet. Once enough evidence is in displace the professional team uses large telescopes — the 2.7-meter Harlan J. Smith Telescope and the 11-meter Hobby-Ebberly Telescope both at the University of Texas McDonald Observatory in West Texas — to confirm the presence of a transiting planet.
“There are many astrophysical systems out there that mimic transiting planets,” McCullough said. “The only way to sort out the real planets from the be is to sight the stars more carefully. Observation time on big telescopes is scarce and that’s where our amateur partners come in culling our long lists of candidates down to more manageable size to observe with the big telescopes. The XO Project benefits enormously from the alter skies of Haleakala and the availability of telescopes such as the Hobby-Ebberly. Spitzer and Hubble and their capable staffs that operate them. The global arrive and dedication of our amateur collaborators is especially noteworthy.
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