Not the mother of meteorites

The region between Mars and Jupiter is teeming with rocky worlds called asteroids. This asteroid belt is estimated to contain millions of small rocky bodies, and between 1.1 and 1.9 million larger ones spanning over one kilometre across. Small fragments of these bodies often fall to Earth as meteorites. Interestingly, 34% of all meteorites found on Earth are of one particular type: H-chondrites. These are thought to have originated from a common parent body — and one potential suspect is the asteroid 6 Hebe, shown here.

Approximately 186 kilometres in diameter and named for the Greek goddess of youth, 6 Hebe was the sixth asteroid ever to be discovered. These images were taken during a study of the mini-world using the SPHERE instrument on ESO’s Very Large Telescope, which aimed to test the idea that 6 Hebe is the source of H-chondrites.

Astronomers modelled the spin and 3D shape of 6 Hebe as reconstructed from the observations, and used their 3D model to determine the volume of the largest depression on 6 Hebe — likely an impact crater from a collision that could have created numerous daughter meteorites. However, the volume of the depression is five times smaller than the total volume of nearby asteroid families with H-chondrite composition, which suggests that 6 Hebe is not the most likely source of H-chondrites after all.

Links

• Research paper