Kepler discovers the first Earth-sized exoplanet, dubbed Kepler-186f, in the habitable zone of another Star. Watch the video… An artist’s conception of Kepler-186f Credit: NASA Ames/SETI Institute/JPL-CalTech
The Kepler-186f is the fifth planet discovered orbiting the red dwarf star Kepler-186, located 490 light-years away from us.
The newly discovered planet completes one orbit around its star every 130 days and is located in the system’s habitable zone.
NASA’s Kepler Space Telescope has discovered the first validated Earth-size planet orbiting in the habitable zone of a distant star, an area where liquid water might exist on its surface. The planet, Kepler-186f, is ten percent larger in size than Earth and orbits its parent star, Kepler-186, every 130 days. The star, located about 500 light-years from Earth, is classified as an M1 dwarf and is half the size and mass of our sun.
Paul Hertz, NASA’s Astrophysics Division director at the agency’s headquarters in Washington, said:
“The discovery of Kepler-186f is a significant step toward finding worlds like our planet Earth. Future NASA missions, like the Transiting Exoplanet Survey Satellite and the James Webb Space Telescope, will discover the nearest rocky exoplanets and determine their composition and atmospheric conditions, continuing humankind’s quest to find truly Earth-like worlds.”
Although the size of Kepler-186f is known, its mass and composition are not. Previous research, however, suggests that a planet the size of Kepler-186f is likely to be rocky.
Elisa Quintana, research scientist at the SETI Institute at NASA’s Ames Research Center in Moffett Field, Calif., and lead author of the paper published today in the journal Science, said:
“We know of just one planet where life exists — Earth. When we search for life outside our solar system we focus on finding planets with characteristics that mimic that of Earth. Finding a habitable zone planet comparable to Earth in size is a major step forward.”
Thomas Barclay, research scientist at the Bay Area Environmental Research Institute at Ames, and co-author of the paper, said:
“Being in the habitable zone does not mean we know this planet is habitable. The temperature on the planet is strongly dependent on what kind of atmosphere the planet has. Kepler-186f can be thought of as an Earth-cousin rather than an Earth-twin. It has many properties that resemble Earth.”
The next steps in the search for distant life include looking for true Earth-twins — Earth-size planets orbiting within the habitable zone of a sun-like star — and measuring the their chemical compositions. The Kepler Space Telescope, which simultaneously and continuously measured the brightness of more than 150,000 stars, is NASA’s first mission capable of detecting Earth-size planets around stars like our sun.
The discovery of Kepler-186f, published in Science.
source NASA Kepler