By Meleasie Goviro – EM TV International
Astronomers on Monday announced the discovery of three new Earth-sized planets said to be orbiting a small, dim star commonly known as an ultra-cool dwarf.
Scientists believe that these planets may be key targets for observation in their search for life on other planets.
The discovery was made using Europe’s Transiting Planets and Planetesimals Small Telescope, or TRAPPIST, located at the La Silla Observatory in Chile.
The telescope finds planets by detecting changes in the amount of light coming from a star that may be caused by a planet passing by the telescope’s line of sight.
The Earth-sized planets are orbiting their parent star, located in the constellation Aquarius, 40 light years away from Earth.
Scientists observed that the planets are located idyllically to access enough heat for there to be liquid water on their surface, a condition that they consider to be critical for fostering life.
Their host star, TRAPPIST-1, is much cooler and redder than the sun; about 8 per cent of its size and under half as bright, scientists said.
Ultra-cool dwarf stars like this one are widely common in the solar system and long lived, but this is the first time planets were discovered orbiting one.
So far, astronomers have found over 2,000 planets beyond the solar system and are developing techniques to scan their atmospheres for gases that indicate biological activity.