Cassiopeia is a constellation named for a queen in Greek mythology. Cassiopeia was the mother of Andromeda. She incurred the wrath of Poseidon by boasting about Andromeda's and her own beauty.
In Battlestar Galactica, Cassiopeia was a medtech, and former prostitute.
In Transformers, Cassiopeia was a reporter for Around Cybertown.
Cassiopeia was a mage in League of Legends video game.
In the Harry Potter series, Cassiopeia Black was the daughter of Cygnus Black II and Violetta Bulstrode. She was the grand-aunt of Sirius Black.
The name is Greek in origin, and means "cassia juice." In 2014, the name Cassiopeia was given to 12 girls in the United States. Cassiopeia is a more unique way to get to the nickname 'Cassie'.