NASA’s Spitzer Space Telescope has discovered a system of seven Earth-size planets surrounding a single star. Liquid water could be present in all the seven planets. But the chances are the highest in three of these planets situated in the habitable zone, the region around the parent star where it is more probable for a planet to have liquid water.
"This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life" said Thomas Zurbuchen, the NASA’s Science Mission Directorate’s associate administrator.
One of the top priorities of science is to find an answer to the question “Are we alone?” Finding several habitable planets for the first time is an exceptional step forward towards that objective.
This exoplanet system located approximately 40 light-years away from earth has been named TRAPPIST-1 (The Transiting Planets and Planetesimals Small Telescope). On the basis of their densities, all the planets of the TRAPPIST-1 are estimated to be rocky. These new discoveries have been published in the Nature journal.
Following these discoveries, NASA’s Hubble Space Telescope has begun the scrutinizing of four of the seven planets, including the three in the habitable zone.