U.S. astronomers have discovered the first planet outside our solar system that meets the conditions of temperature and gravity to be habitable.
This 'exoplanet', as reported finding those responsible, is at the center of a "habitable zone", at a distance a star where get enough energy for liquid water on its surface and therefore support life. The habitability of a planet depends on several conditions, but the existence of liquid water and atmosphere are two of the most important factors for life to exist.
On this planet, 20 light years from Earth and orbiting the star Gliese 581, scientists have detected the terms "right" to have water temperature, gravity and atmosphere there. "The planet is at the correct distance (star) so that no water or very hot or very cold, and with a severity similar to that of the Earth that has an atmosphere," explained at a conference one of the scientists in charge of the investigation, Steven Vogt.
The discovery of the planet is detailed in a study published in the Astrophysical Journal and is based on eleven years of research at the observatory W M. Hawaii's Keck (USA), funded by the National Science Foundation and the U.S. space agency NASA.
Three or four times the mass of Earth
discovered the planet's mass is three to four times larger than Earth and its orbit around the star is 37 days. Scientists say it is a planet that is orbiting around the star Gliese 581, in the constellation Libra, and is "probably" rocky, with a firm surface with enough gravity to hold an atmosphere.
Other scientists had noted before the discovery of two potentially habitable planets around the same star at the edge of the area considered suitable to live. In the nearest hot star, the planet was found 'c' and the far, cold planet 'd'. However, only a few astronomers believed that the second could be eligible for habitation if he had a thick atmosphere and a strong greenhouse effect that could be heated.
Instead, found the new planet, named "Gliese 581 g ', is right in the center of the area considered habitable. In addition, one side is always facing the star and enjoying life in daylight, while the other side faces the opposite side of the star and is in perpetual darkness.
