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takyon [soylentnews.org] writes:

A Jupiter-like exoplanet has been discovered orbiting its star with an eccentricity more similar to a comet than a planet [sfsu.edu]:

Led by SF State astronomer Stephen Kane, a team of researchers has spotted an extrasolar planet about 117 light-years from earth that boasts the most eccentric orbit yet seen.

What's more, Kane and his colleagues were able to detect a signal of reflected light from the planet known as HD 20782 — a "flash" of starlight bouncing off the eccentric planet's atmosphere as it made its closest orbital approach to its star. The discovery was announced online Feb. 28 in The Astrophysical Journal. [...] HD 20782 has the most eccentric orbit known, measured at an eccentricity of .96. This means that the planet moves in a nearly flattened ellipse, traveling a long path far from its star and then making a fast and furious slingshot around the star at its closest approach.

[...] At the furthest point in its orbit, the planet is separated from its star by 2.5 times the distance between the sun and Earth. At its closest approach, it ventures as close as .06 of that same Earth-sun distance — much closer than Mercury orbits the sun, said Kane, an assistant professor of physics and astronomy. "It's around the mass of Jupiter, but it's swinging around its star like it's a comet."

Evidence for reflected light from the most eccentric exoplanet known [arxiv.org]

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