University of Liège discovers new Earth-sized planet, the Speculoos-3 b

23/05/2024

Astronomers from the University of Liège have made their mark with the discovery of an Earth-sized planet: Speculoos-3 b.

Speculoos, the famous coffee biscuit, is light years away from Speculoos-3 b, the exoplanet. The latter is a planet located outside our solar system, the Milky Way. In this case, a mere 55 light years away from us. That’s relatively close, when you consider that the Milky Way extends over 100,000 light years.  

Speculoos-3 b is about the same size as Earth and orbits the nearby red ultra-cold dwarf star Speculoos-3 in just 17 hours. That's how long - or rather how short - a year lasts there. And it is likely that one side is always facing the star and the other always facing away, so that the day side is perpetually bathed in light and the night side perpetually in darkness.  

Unlike our home planet, Speculoos-3 b is very unlikely to have an atmosphere. It is too close to its star for that. As such, it faces high-energy radiation, receiving 16 times more energy per second than Earth receives from the Sun. Life is all but impossible in those circumstances, but additional research is needed to confirm that. 

And whence the strange name, SPECULOOS? The acronym stands for Search for Planets EClipsing Ultra-cOOl Stars, a project launched by the University of Liège in 2019 to detect habitable exoplanets orbiting the coldest and smallest stars near the Sun.