GJ1214b : Picture and Video GJ1214b- GJ 1214 b is an extrasolar planet that orbits the star GJ 1214b. The parent star is 13 parsecs (approximately 40 light-years) from the Sun, in the constellation Ophiuchus. The planet was discovered in December 2009. It is classified as a super-Earth because it is larger than Earth but has a mass and radius significantly less than those of the gas giants in the Solar System.
After COROT-7b, it is the second such planet to be known and is the first of a new class of planets with small size and relatively low density. GJ 1214 b is also significant because its parent star is relatively near the Sun and because it transits (crosses in front of) that parent star, which allows the planet's atmosphere to be studied using spectroscopic technologies.
Detection
GJ 1214 b was first detected by the MEarth Project, which searches for the small drops in brightness that can occur when an orbiting planet briefly passes in front of its parent star.
In early 2009, the astronomers running the project noticed that the star GJ 1214 appeared to show drops in brightness of that sort. They then observed the star more closely and confirmed that it dimmed by roughly 1.5% every 1.58 days.
Follow-up radial-velocity measurements were then made with the HARPS spectrograph on the ESO's 3.6-meter telescope at La Silla, Chile; those measurements succeeded in providing independent evidence for the reality of the planet. A paper was then published in Nature announcing the planet and giving estimates of its mass, radius, and orbital parameters.
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