For the first time, scientists may have discovered an exomoon located 133 light-years from Earth

Many mysteries still remain in the universe, and this is the case of the exomoons. As a reminder, these are moons orbiting exoplanets, which are planets located outside the solar system. And if today, no exomoon has been officially discovered, this may soon change. 

Researchers recently published a study highlighting a new candidate. And for that, we must turn to HD 206893 b, which is located about 133 light-years from Earth. It is a gas giant, discovered in 2021, which orbits an F-type star in 25,6 years at a distance of 9.6 AU. Its dimensions are also impressive, as its mass is 28 times that of Jupiter.

Thus, in order to detect a celestial object orbiting this exoplanet, scientists used astrometry. This method allows them to detect orbital variations between different stars and different planets. And it was with the help of VLTI/GRAVITY that they discovered an object that seems to be orbiting HD 206893 b, and could have a mass equivalent to 0.4 times that of Jupiter. In other words, this potential exomoon would be small, which explains why scientists have had difficulty observing it and confirming its existence.

Indeed, currently, no exomoon has been officially discovered, and there are very few candidates like Kepler-1625 b and Kepler-1708 b. However, it is an important subject, notably concerning the search for potential traces of life elsewhere in the universe. And if our solar system has more than 200 moons, some of which could harbor life, such as Enceladus, this discovery could lead to new studies and a better understanding of our universe.