Topic summary
Stellar stream
Extracted from the Wikipedia article Stellar kinematics.
Stellar streams
A stellar stream is an association of stars orbiting a galaxy taking the appearance of an elongated stream of stars. Stars that are part of stellar streams were often once part of a globular cluster or dwarf galaxy. However, their original system has now been torn apart and stretched out along its orbit by the tidal forces of the larger galaxy. Stellar streams are crucial for the understanding of galaxy interaction. They show the history of that galaxy and that interactions between galaxies are still happening in the modern Universe. The study of stellar streams were often limited to those that are local, orbiting around the Milky Way.