Astronomers Have Detected An Earth-sized Exoplanet Orbiting

Just 55 light-years away from Earth, a new planet the size of Earth has been discovered by astronomers orbiting an extremely chilly red dwarf star.

A result of the Search for Planets EClipsing ULtra-cOOl Stars (SPECULOOS) project, which is led by the University of Liège in Belgium in association with other universities, is the most recent discovery. SPECULOOS-3b, the recently discovered planet orbiting SPECULOOS-3, is a highly excellent dwarf star with an average temperature of about 2,600°C. SPECULOOS-3b is a remarkable object; it completes its orbit in a mere 17 hours and is probably tidally locked, meaning that one side of it is always facing the star.

“A year, i.e., an orbit around the star, lasts 17 hours. Days and nights, on the other hand, should never end. We believe that the planet rotates synchronously so that the same side, the day side, always faces the star, just like the Moon does for the Earth. On the other hand, the night side would be locked in endless darkness,” explained Michaël Gillon, the study’s lead author.

The Milky Way is a whole of ultra-cool dwarf stars, considered the universe’s least massive stars. About the size of Jupiter, SPECULOOS-3 is ten times less massive, twice as cold, and half as bright as our Sun. These stars are difficult to study because of their low luminosity, but they have an exciting lifespan of up to 100 billion years longer than our Sun.

Utilizing the SPECULOOS South Observatory in Chile’s Atacama Desert and a network of SPECULOOS telescopes in the Northern Hemisphere, the SPECULOOS-3b discovery was made. “SPECULOOS-3’s discovery demonstrates that our global network is operating effectively and prepared to find further rocky worlds orbiting shallow mass stars. According to Amaury Triaud, a professor of exoplanetology at the University of Birmingham, “Ultra-cool dwarf stars are cooler and smaller than our sun, but they have a lifespan that is over a hundred times longer, around 100 billion years, and they are expected to be the last stars still shining in the Universe.”

Due to the star’s extended life, the orbiting planets may have more chances to support life. The scientific team intends to conduct follow-up studies using the James Webb Space Telescope (JWST) to learn more about surface materials and the potential presence of an atmosphere. The JWST may also disclose the composition of the planet’s surface rocks.

The Massachusetts Institute of Technology, Cambridge, and Bern universities contributed to the SPECULOOS project.