Found: An Earth-sized exoplanet named SPECULOOS-3 b

An artist's concept of the exoplanet SPECULOOS-3 b orbiting its red dwarf star. The planet is as big around as Earth, while its star is slightly bigger than Jupiter - but much more massive. Credit: NASA/JPL-Caltech

An international team of astronomers has discovered exoplanet SPECULOOS-3 b and its ultra-cool red dwarf star, some 55 light-years away from Earth.

Despite being the size of Earth, the newly discovered exoplanet could not be more different from our home planet. According to the NASA news release from May 15, this terrestrial world is baked by high levels of radiation from its sun, probably leaving the planet without an atmosphere. It orbits its star in 17 hours, as opposed to our year. And the planet is likely tidally locked, meaning one side always faces the sun while the other is shrouded in darkness.

The red dwarf star is also very different from our own Sun: The Jupiter-sized SPECULOOS-3 was discovered to be 4,760 degrees Fahrenheit (2,627 degrees Celsius), several thousand degrees cooler than the Sun, and much dimmer as well.

The discovery of this exoplanet comes from the Belgium-based SPECULOOS (Search for Planets EClipsing ULtra-cOOl Stars) project, an international network of telescopes in search for dim stars in our galaxy and the rocky planets that orbit them. The goal is to identify dozens of planetary systems and even more red dwarfs, in the hope of finding habitable exoplanets and signs of life. The name of the mission is a play on words with the Belgian speculoos cookies (which fans of Trader Joe's may recognize too).

The data from SPECULOOS-3 b discovery could lead to further research using the James Webb Space Telescope, according to the release. Its planetary composition and its location are subject to more research.

''We're making great strides in our study of planets orbiting other stars. We have now reached the stage where we can detect and study Earth-sized exoplanets in detail. The next step will be to determine whether any of them are habitable, or even inhabited,'' said Steve B. Howell, one of the planet's discoverers at NASA Ames Research Center, in the release.