2006/09/15 by C. J. Grillmair, Carl J. Grillmair · 6 citations
Physics and Astronomy · #Astronomy #Astrophysics #Dwarf galaxy #Dwarf spheroidal galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gamma-ray bursts and supernovae #Globular cluster #Interacting galaxy #Physics #Population #Sky #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/509255
published as Astrophys.J.651:L29-L32,2006 · 11 pages, 4 figures, accepted for publication in ApJ Letters
arxiv created 2006/09/15 · openalex publication_date 2006/10/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report on the detection in Sloan Digital Sky Survey data of at least three, roughly parallel components in a 65°-long, stellar stream complex previously identified with the Monoceros Ring. The three-stream complex varies in width from 4° to 6° along its length and appears to be made up of two or more narrow substreams as well as a broader, diffuse component. The width and complexity of the stream indicate that the progenitor was likely a dwarf galaxy of significant size and mass. The stream is 8.9 kpc distant and is oriented almost perpendicularly to our line of sight. The visible portion of the stream does not pass near any known dwarf galaxies, and a preliminary orbit does not point to any viable progenitor candidates. Orbits for the narrower substreams can be modeled with velocity offsets from the broad component of ≈8 km s -1 . We suggest that the broad component is likely to be the remains of a dwarf galaxy, while the narrower streams constitute the remnants of dynamically distinct components that may have included a native population of globular clusters. While the color of the main-sequence turnoff is not unlike that for the Monoceros Ring, neither the visible stream nor any reasonable projection of its orbit passes through Monoceros or Canis Major, and we conclude that this stream is probably unrelated to the overdensities found in these regions.