An artist's illustration of a recently confirmed Jupiter-mass planet orbiting the nearby, Sun-like star Epsilon Eridani.
Credit: NASA, ESA, G.F. Benedict (University of Texas, Austin)
The closest planet outside our solar system orbits a young Sun-like star only 10.5 light years away--so close that telescopes might soon be able to snap pictures of it, new observations confirm.
About 1.5 more massive than Jupiter, the planet takes 7-years to circle its star, Epsilon Eridani. The giant gas planet was originally detected in 2000, when astronomers noticed a rocking motion in the star which they attributed to the gravitational tug of an unseen planet. Astronomers recently confirmed the wobbles and the planet's existence with NASA's Hubble Space Telescope.
Astronomers think enough starlight might be reflected off the planet [image] when it makes its nearest approach to Epsilon Eridani in 2007 for Hubble and other telescopes to image it.
The Hubble observations also revealed that the planet orbits Epsilon Eridani on the same plane as the star's disk of gas and dust. The finding marks the first time that the two objects have been observed at the same inclination around the same star and supports the theory that planets form from such disks.
If moons circle the planet, they might have temperatures similar to Earth's and possibly liquid water, said study team-member Fritz Benedict at the University of Texas.
However, the planet's orbit takes it so far from its star that any oceans on the moons would freeze. However, life could potentially survive on such moons if they were massive enough to retain a dense heat-trapping atmosphere like Saturn's moon, Titan, Benedict added.
A second planet with a longer orbit might also circle Epsilon Eridani, but this has yet to be confirmed, fellow team member, Barbara McArthur, also of the University of Texas, told SPACE.com.
The study was presented today at the 38th Annual Division of Planetary Sciences Meeting in Pasadena California, and will be detailed in the Nov. issue of Astronomical Journal.
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