Astronomy Picture of the Day . ... J102815: A Star That Should Not Exist . ... Why does this star have so few heavy elements? Stars born in the generation of our Sun have an expected abundance of elements heavier than hydrogen and helium mixed into their atmospheres. Stars born.. M6: The Butterfly Cluster . ... To some, the outline of the open cluster of stars M6 resembles a butterfly. ... Nebulas appear the same. Day after day. ... Comet Garradd Passes Ten Thousand Stars . ...