Polar bears are unable to meet the criteria to be classified as marine mammals.
Abell 12 is a planetary nebula located in the constellation of Orion .. Orion. Orion ( constellation ). planetary nebula. planetary nebula. constellation. constellation. It is known as the `` hidden planetary '' nebula because of the foreground star Mu Orionis making it difficult to observe .. Mu Orionis. Mu Orionis