This strange planet suddenly passes very close to its star, possessing the most eccentric orbit ever observed.
Scientists have discovered an “extrasolar” planet situated 117 light-years from Earth that is the most eccentric cosmic object astronomers have ever seen.
Eccentric, in this case, refers to an extreme elliptical orbit that takes this planet close to the host star and then slingshots it far, far away, before it finally returns for another pass, according to a San Francisco State University statement.
The planet, HD 20782, as an eccentricity of .96, which means it moves on an almost flattened elipse, traveling as far as 2.5 times the distance between the sun and the Earth before swinging around its star very close, coming at .06 of the same Earth-Sun distance. That’s closer than Mercury is to the sun.
And it’s not a small planet. It’s about the size of Jupiter, but it acts like a comet — a pretty bizarre planet by scientific standards.
Scientists found the planet by detecting a flash of starlight bouncing from the atmosphere of the planet as it neared its closest point to the star.
The discovery is not just for curiosity’s sake — it could help scientists learn more about how a planet could possibly survive a sudden, tremendous exposure to the energy of a star.
San Francisco State University astronomer Stephen Kane said in the statement that extrasolar planets like HD 20782 contain a wealth of questions for astronomers: “When we see a planet like this that is in an eccentric orbit, it can be really hard to try and explain how it got that way,” he said. “It’s kind of like looking at a murder scene, like those people who examine blood spatter patterns on the walls. You know something bad has happened, but you need to figure out what it was that caused it.”
In the case of HD20782, the suspects could be that there was more than one planet in the system and two planets got too close together, or the planet is in a binary star system.