Cassiopeia OB1 is a stellar association located in the constellation Cassiopeia. It consists of a group of young, hot stars that are primarily of spectral types O and B, which are known for their high temperatures and brightness. This association is estimated to be around 10 million years old and is situated approximately 2,500 light-years away from Earth. The stars in Cassiopeia OB1 are not gravitationally bound, meaning they are moving through space independently. This group is part of a larger region of star formation and is associated with the Cassiopeia constellation's rich nebulae, contributing to the overall beauty and complexity of the night sky in that area.