TRAPPIST-1

TRAPPIST-1 is an ultra-cool dwarf star located approximately 39.6 light-years away from the Sun in the constellation Aquarius. It is named after the TRAPPIST telescope which discovered two of its seven known exoplanets in 2016. The star and its planetary system are notable for the relatively small size of the star and the close proximity of the planets to the star, which has allowed for detailed observations and has led to significant discoveries about the nature of exoplanets and their atmospheres.

Characteristics

TRAPPIST-1 is an ultra-cool dwarf star, a category of stars that are cooler and less massive than red dwarf stars. It has approximately 8% the mass of the Sun and 11% its radius, making it slightly larger than the planet Jupiter. Despite its small size, TRAPPIST-1 is quite dense and has a similar temperature to other dwarf stars.

Planetary system

The TRAPPIST-1 system is known to contain seven terrestrial (rocky) planets, all of which are similar in size to Earth. These planets orbit very close to the star, with periods ranging from 1.5 to 20 Earth days. This close proximity allows for the possibility of tidal locking, where one side of the planet always faces the star, similar to how the Moon is tidally locked to Earth.

Three of the planets (TRAPPIST-1e, f, and g) are located in the star's habitable zone, where conditions might be right for liquid water to exist on the surface. However, the star's low temperature and the planets' close orbits could result in a variety of climate conditions, some of which might not be conducive to life as we know it.

Discovery and observation

The TRAPPIST-1 system was discovered by the TRAPPIST telescope in 2016. The telescope, located at the European Southern Observatory in Chile, is dedicated to searching for exoplanets around ultra-cool dwarf stars. The discovery of the TRAPPIST-1 system marked a significant milestone in the search for habitable exoplanets.

Since the initial discovery, additional observations have been made by other telescopes, including the Spitzer Space Telescope and the Hubble Space Telescope. These observations have provided detailed information about the planets' sizes, compositions, and atmospheres.

See also

• List of nearest stars and brown dwarfs
• List of potentially habitable exoplanets