Editing Canis Major Overdensity (section)

==Discovery==

The existence of a strong elliptical-shaped stellar overdensity was reported in November 2003 by an international team of French, Italian, British, and Australian [[astronomer]]s, who claimed their study pointed to a newly discovered dwarf galaxy: the Canis Major Dwarf Galaxy.<ref name="Martin2003">{{Cite journal |last1=N. F. Martin |last2=R. A. Ibata |last3=M. Bellazzini |last4=M. J. Irwin |last5=G. F. Lewis |last6=W. Dehnen |year=2004 |title=A dwarf galaxy remnant in Canis Major: the fossil of an in-plane accretion onto the Milky Way |journal=Monthly Notices of the Royal Astronomical Society |volume=348 |issue=12 |pages=12 |arxiv=astro-ph/0311010 |bibcode=2004MNRAS.348...12M |doi=10.1111/j.1365-2966.2004.07331.x|doi-access=free |s2cid=18383992 }}</ref> This structure is located closer to the [[Sun]] than the center of this galaxy, at approximately {{convert|7.7|kpc|ly|abbr=on|lk=on}} from the Sun.

The team of astronomers that discovered it was collaborating on analysis of data from the [[2MASS|Two-Micron All Sky Survey]] (2MASS), a comprehensive survey of the sky in [[infrared]] light, which is not blocked by gas and dust as severely as visible light.  Because of this technique, scientists were able to detect a very significant overdensity of [[Stellar classification|class M]] giant stars in a part of the sky occupied by the Canis Major constellation, along with several other related structures composed of this type of star, two of which form broad, faint arcs.