Field of Streams

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The Field of Streams is a patch of sky where several stellar streams are visible and crisscross.

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It was discovered by Vasily Belokurov and Daniel Zucker's team in 2006 by analyzing the Sloan Digital Sky Survey II (SDSS-II) data. The team named the area Field of Streams because of so many crisscrossing trails of stars. [1]

The Sagittarius Stream of the Sagittarius Dwarf Elliptical Galaxy (SagDEG) dominates the Field. It has a split trail within the area of the Field of Streams, because SagDEG has wrapped around the Milky Way Galaxy multiple times, which has resulted in overlapping trails. The forking of the trail has made it possible to infer the organization of dark matter in the inner halo of the Milky Way Galaxy, resulting in the determination that it is distributed in a round spherical manner, as opposed to the expected flattened spheroid. The shape of the streams also implies that the dark matter is very cold, due to the thin trails, and persisting existence. [2]

Also appearing in the Field is the Monoceros Ring, which was discovered before the Field. [3]

See also

Related Research Articles

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Canes Venatici II or CVn II is a dwarf spheroidal galaxy situated in the Canes Venatici constellation and discovered in 2006 in data obtained by the Sloan Digital Sky Survey. The galaxy is located at a distance of about 150 kpc from the Sun and moves towards the Sun with the velocity of about 130 km/s. It is classified as a dwarf spheroidal galaxy (dSph) meaning that it has an elliptical shape with a half-light radius of about 74+14
−10
 pc
.

Coma Berenices or Com is a dwarf spheroidal galaxy situated in the Coma Berenices constellation and discovered in 2006 in data obtained by the Sloan Digital Sky Survey. The galaxy is located at the distance of about 44 kpc from the Sun and moves away from the Sun with the velocity of about 98 km/s. It is classified as a dwarf spheroidal galaxy (dSph) meaning that it has an elliptical shape with the half-light radius of about 70 pc.

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In astronomy, the Sagittarius Stream is a long, complex structure made of stars that wrap around the Milky Way galaxy in an orbit that nearly crosses the galactic poles. It consists of tidally stripped stars from the Sagittarius Dwarf Elliptical Galaxy, resulting from the process of merging with the Milky Way over a period of billions of years.

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<span class="mw-page-title-main">Gaia Sausage</span> Remains of a galaxy merger in the Milky Way

The Gaia Sausage or Gaia Enceladus is the remains of a dwarf galaxy that merged with the Milky Way about 8–11 billion years ago. At least eight globular clusters were added to the Milky Way along with 50 billion solar masses of stars, gas and dark matter. It represents the last major merger of the Milky Way.

References

  1. SDSS, "Multiple galaxy mergers continue in the Milky Way", 2006 May 8 (accessed 2009 March 29)
  2. SpaceDaily, "Milky Way A Field Of Streams", 2006 May 9 (accessed 2009 March 29)
  3. SDSS, "Map of stars in the outer regions of the Milky Way Galaxy", V. Belokurov, Sloan Digital Sky Survey (accessed 2009 March 29) Archived March 19, 2009, at the Wayback Machine

Sources