Planet-Swallowing Star Eats for Two
Have you ever ordered a dinner for two... for just yourself? Apparently, the growing star Kepler-56 is doing just that. Astronomers have determined that Kepler-56 will be swallowing two of its orbiting planets whole as it becomes a red giant. "As far as we know, this is the first time two known exoplanets in a single system have a predicted 'time of death,'" Gongjie Li of the Harvard-Smithsonian Center for Astrophysics (CfA) said in a recent statement.
Read more at Nature World News
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Mystery World Baffles Astronomers
Kepler-78b is a planet that shouldn't exist. This scorching lava world circles its star every eight and a half hours at a distance of less than one million miles - one of the tightest known orbits. According to current theories of planet formation, it couldn't have formed so close to its star, nor could it have moved there. "This planet is a complete mystery," says astronomer David Latham of the Harvard-Smithsonian Center for Astrophysics (CfA). "We don't know how it formed or how it got to where it is today. What we do know is that it's not going to last forever."
A Giant Cosmic Misalignment
A long-standing puzzle in the study of exoplanets is the formation of hot Jupiters, gas giant planets that snuggly orbit their host star. To explain their short orbital periods, theory suggests that hot Jupiters form in long orbits and then quiescently migrate through the protoplanetary disc, the flat ring of dust and debris that circles a newly fashioned star and coalesces to form the planets. This theory was challenged when the orbital plane of hot Jupiters were discovered to be frequently misaligned with the equator of their host stars. Scientists interpreted this as evidence that hot Jupiters are the result of chaotic close encounters with other planets.
Read the paper at Science
Read Discovery of water vapor in the atmosphere of a giant exoplanet
The alien world, known as Tau Boötis b, Tau Boötis Ab or the Millennium Planet, was discovered in 1996. It is a so-called hot-Jupiter that orbits closely around its host star every 3 days 7.5 hours. Located in the constellation of Boötes, around 51 light-years away from our planet, Tau Boötis b has a mass almost six times that of Jupiter. “Planets like Tau Boötes b, which are as massive as Jupiter but much hotter, do not exist in our Solar System,” said Dr Chad Bender from Penn State University, who is a co-author of the paper published in the Astrophysical Journal Letters (Lockwood, Johnson et al.).