About Trappist-1: TRAPPIST-1 is an ultra-cool red dwarf star in the constellation Aquarius. It has a mass of about 9% that of the Sun, a radius slightly larger than the planet Jupiter, and a surface temperature of about 2,566 K (2,293 °C). The star is 40.7 light-years (12.47 pc) from the Sun and is estimated to be 7.6 billion years old, making it older than the Solar System. It was discovered in 2000. In 2016 and 2017, observations with numerous space- and ground-based telescopes, including the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) telescope at La Silla Observatory, led to the discovery of two terrestrial planets in orbit around the star. An additional signal in the data was later found to be the result of five planets, bringing the total to seven. The orbital periods – the time it takes for each planet to orbit the star – have precise numerical ratios of 8:5, 5:3, 3:2, 3:2, 4:3, and 3:2. This orbital resonance could have existed since the formation of the planetary system. The planets are likely to be tidally locked to TRAPPIST-1, which forces them to keep the same side facing their host star.
