Discovery of New Planetary Systems

 

 TRAPPIST-1

TRAPPIST-1, also designated as 2MASS J23062928-0502285, is an ultra-cool dwarf star located 39.5 light-years (12.1 parsecs) from the Sun in the constellation Aquarius . As of February 2017, it has been shown to host seven terrestrial planets, a larger number than detected for any otherplanetary system.

Astronomers first discovered three Earth-sized planets orbiting the dwarf star in 2015. A team led by Michaël Gillon at the University of Liège in Belgium detected the planets using transit photometry with the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) at the La Silla Observatory inChile. On 22 February 2017, astronomers announced four additionalexoplanets around TRAPPIST-1. 

This work used the NASA Spitzer Space Telescope and the Very Large Telescope at Paranal, among others, and brought the total number of planets to seven, of which three are considered to be within its habitable zone; conceivably, the others also could be habitable insofar as they may possess liquid water somewhere on their surface.