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OGLE-2005-BLG-390Lb





artist's impression of a rocky exoplanet.html
Artist's illustration of an icy/rocky planet orbiting a dim star.
Credit: NASA, ESA and G. Bacon (STScI)

The most Earth-like extrasolar planet discovered to date, in terms of its mass and distance from its parent star. OGLE-2005-BLG-390Lb has just five times the Earth's mass. It orbits a red dwarf star some 25,000 light-years away.

OGLE-2005-BLG-390Lb was found by the technique of microlensing. Its discovery involved a collaboration of three microlensing campaigns, PLANET/RoboNet, OGLE, and MOA, and researchers from 12 countries.

OGLE-2005-BLG-390Lb is almost certainly a terrestrial-type planet, made mostly of rock with a metallic core, like the Earth. However, its large orbit and cool parent star must make it a very frigid place; its estimated surface temperature is -220°C (-364°F). OGLE-2005-BLG-390Lb takes about 10 years to go around its orbit, which is roughly three times bigger than Earth's orbit around the Sun.


Related categories

   • EXTRASOLAR PLANETS AND SUBSTELLAR OBJECTS
   • ASTROBIOLOGY