This chart compares the smallest known exoplanets, or planets orbiting outside the solar system, to our own planets Mars and Earth. Astronomers using data from NASA's Kepler mission and ground-based telescopes recently discovered the three smallest exoplanets known to circle another star, called KOI-961.01, KOI-961.02 and KOI-961.03. The smallest of these, KOI-961.03, is about the size of Mars with a radius of only 0.57 times that of Earth. Not long ago, in Dec. of 2011, the Kepler team announced the discovery of Kepler-20e and Kepler-20f -- the first Earth-size planets ever found outside the solar system. All five of these small exoplanets have toasty orbits close to their stars, and do not lie in the more temperate habitable zone.
The ground-based observations contributing to the KOI-961 discoveries were made with the Palomar Observatory, near San Diego, Calif., and the W.M. Keck Observatory atop Mauna Kea in Hawaii.
Kepler 22-b : como la tierra pero a 600 años luz(*)
This artist's conception compares the KOI-961 planetary system to Jupiter and the largest four of its many moons. The KOI-961 planetary system hosts the three smallest planets known to orbit a star beyond our sun (called KOI-961.01, KOI-961.02 and KOI-961.03). The smallest of these planets, KOI-961.03, is about the same size as Mars. All three planets take less than two days to whip around their star.
The planets were discovered using data from NASA's Kepler mission and ground-based telescopes. The KOI-961 star is a tiny "red dwarf," just one-sixth the size of our sun. This planetary system is the most compact detected to date, with a scale closer to Jupiter and its moons than another star system.
The planet and moon orbits are drawn to the same scale. The relative sizes of the stars, planets and moons have been increased for visibility.
No comments:
Post a Comment