Tidal stream

In galactic terms, a tidal stream is a massive stream of interstellar gas and other material, such as stray star systems, left over by the gravitational tidal forces of interacting galaxies. Tidal streams are a common occurrence within the Inter-Galactic Voids around galaxies, including the Milky Way; the Sagittarius Tidal Stream is just one such example. Another is Palomar 5, a globular cluster also in the process of being ripped apart by gravitational forces, leaving behind streams of stars 13,000 light years in scale. NGC 5466 is also well known.

On a smaller scale, a tidal stream may refer to material ejecta from gravitational interaction between objects such as ordinary stars and neutron stars or black holes.

See also

• List of galactic tidal streams.