Object Analysis

The Butterfly Cluster (Messier 6) is an open cluster of stars in the constellation of Scorpius. Its name derives from the vague resemblance of its stars to the shape of a butterfly with open wings. It lies roughly 1,600 light-years from Earth.

The cluster is estimated to be 94 million years old. Most of the bright stars in this cluster are hot, blue B-type stars, but the brightest member is actually an orange giant star, BM Scorpii, which contrasts sharply with its blue neighbors.

Visually, the "antennae" of the butterfly are formed by two rows of stars, while the wings are outlined by the brighter members. It is best viewed with binoculars or a wide-field telescope at low magnification.