Linked from
The 13 pages that link to Stellar stream, each with the reason it gives.
Open clusterBroader topic: Some disrupted open clusters leave streams of former members behind.
Stellar kinematicsBroader topic: Coherent motions trace the shared origin of stream stars.
Galactic haloBroader topic: Streams mark recent accretion events still unfolding in a halo.
Galactic tideBroader topic: The Milky Way’s tidal field stretches disrupted systems into streams.