First planet that orbits “backward” around its star found by scientistsAugust 18th, 2009 - 1:41 pm ICT by ANI
Washington, August 18 (ANI): Scientists have found the first planet that orbits “backward” around its star, an eccentricity likely caused by a collision with a larger neighbor early in its life.
According to a report in National Geographic News, the planet, dubbed WASP-17b, orbits a star about a thousand light-years away.
In addition to its exceptionally low density, the planet is one of the largest yet found.
“When I first saw that this thing might have a radius twice that of Jupiter, I was really astounded,” said David Anderson of Keele University, a member of the UK-based Wide Area Search for Planets (WASP) consortium.
WASP-17b probably got so big because of its unusual orbit, Anderson and colleagues said in a new paper describing the find.
The planet is also the first found to orbit “backward” around its star, an eccentricity likely caused by a collision with a larger neighbor early in WASP-17b’s life.
That planetary crash may have nudged WASP-17b into an elongated orbit, which led to variations in the gravitational pull exerted on the planet by its host star, according to Anderson.
Changes in the star’s pull would have generated powerful tidal forces, which in turn would have created friction that got dissipated as heat.
The planet’s heated gases would have then expanded, causing the world to bloat. (ANI)
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