This artist's impression shows one of the three newly discovered planets in the star cluster Messier 67. In this cluster the stars are all about the same age and composition as the Sun. This makes it a perfect laboratory to study how many planets form in such a crowded environment. Very few planets in clusters are known and this one has the additional distinction of orbiting a solar twin — a star that is almost identical to the Sun in all respects.
Illustration credit: ESO/L. Calçada
Note: For more information, see First Planet Found Around Solar Twin in Star Cluster.