‘Just 55-light years away’: Astronomers discover Earth-sized exoplanet orbiting a failed star 

Produced by: Tarun Mishra Designed by: Manoj Kumar

Discovery Details

Astronomers have identified an Earth-size exoplanet orbiting an ultracool red dwarf star, roughly 55 light-years from Earth. The star, similar in size to Jupiter, is 100 times less bright and half as hot as the Sun. The team’s findings were published on May 15 in the journal Nature Astronomy.

SPECULOOS-3 b

The new exoplanet, named SPECULOOS-3 b, marks only the second known planetary system around a red dwarf star. The first known system is the Trappist-1 system.

Credit: NASA/JPL-Caltech

SPECULOOS Project

This discovery was made by the Search for habitable Planets Eclipsing Ultra-cool Stars (SPECULOOS) project, based at the Paranal Observatory in Chile’s Atacama Desert. The project aims to find rocky exoplanets around nearby ultracool stars and brown dwarfs using infrared observations.

Red Dwarfs and Habitability

According to Émeline Bolmont, an assistant professor at the University of Geneva, red dwarfs’ small size makes it easier to detect Earth-size planets and observe their atmospheres. Studies suggest these stars are promising candidates for hosting life.

Orbital Characteristics

SPECULOOS-3 b orbits its star every 17 hours and is likely tidally locked, meaning one side is perpetually in daylight while the other is in eternal darkness.

Potential for Life

Despite its Earth-like size, SPECULOOS-3 b is not habitable due to receiving 16 times more radiation than Earth, preventing the presence of liquid water on its surface.

Red Dwarf Stars

Red dwarfs, or M-dwarfs, make up 70% of the stars in the Milky Way and have lifespans significantly longer than the Sun. They burn their fuel slowly, allowing for potentially longer periods for life to develop.

Research Goals

SPECULOOS aims to improve understanding of red dwarf planets, which remain under-studied due to their low luminosity and the rarity of discovering planets around them. The project’s dedicated network of telescopes observes these stars over weeks to detect transiting planets.

Future Studies with JWST

While SPECULOOS-3 b is not habitable, it is an ideal target for the James Webb Space Telescope (JWST) to study atmospheric retention in planets close to their stars. This could provide insights applicable to the habitable zone planets in the Trappist-1 system.