Canis Major Over density

Canis Major Overdensity

The Canis Major Dwarf Galaxy (CMa Dwarf) or Great Dog Over density (CMa Overdensity) could be a controversial dwarf irregular galaxy within the native cluster, set within the same a part of the sky as the constellation Canis Major.

The supposed little galaxy contains a comparatively high share of red giants Associate in Nursingd is believed to contain an calculable one billion stars altogether.

The Canis Major Dwarf Galaxy is assessed as Associate in Nursing irregular galaxy and is currently thought to be the nighest neighboring galaxy to the Earth's location within the Milky Way, being set regarding twenty five,000 light-years (7.7 kiloparsecs) away from the Solar Syste and 42,000 ly (13 kpc) from the Galactic Center. It has a roughly elliptical form and is believed to contain as several stars because the Sagittarius Dwarf Elliptical Galaxy, the previous contender for closest galaxy to our location in the Milky Way.

• Discovery

The existence of a robust elliptical-shaped stellar overdensity was according in November 2003 by a world team of French, Italian, British and Australian astronomers, who claimed their study pointed to a newly discovered dwarf galaxy: the Canis Major Dwarf Galaxy. This structure is located closer to the Sun than the center of our galaxy, at approximately 7.7 kpc (25,000 ly) from the Sun.

The team of astronomers that discovered it had been collaborating on analysis of information from the Two-Micron All Sky Survey (2MASS), a comprehensive survey of the sky in infrared light, which is not blocked by gas and mud as severely as visible radiation. Because of this system, scientists were able to detect a very significant overdensity of 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.

• Characteristics

Astronomers believe that the dwarf galaxy is within the method of being force apart by the field of force of the a lot of huge galaxy galaxy. The main body of the galaxy is very degraded. Tidal disruption causes an extended filament of stars to path behind it because it orbits the galaxy, forming a fancy round structure typically mentioned because the Monoceros Ring, that wraps around our galaxy thrice.The stream of stars was 1st discovered within the early twenty first century by astronomers conducting the Sloan Digital Sky Survey. It was within the course of work this ring of stars, and a closely spaced cluster of ball-shaped clusters kind of like those related to the Sagittarius Dwarf Elliptical Galaxy, that the Great Dog Dwarf Galaxy was discovered.

Globular clusters thought to be associated with the Great Dog Dwarf galaxy embrace NGC 1851, NGC 1904, NGC 2298 and NGC 2808, all of which are likely to be remnants of the galaxy's ball-shaped cluster system before its accretion, or swallowing, into the galaxy. NGC 1261 is another close cluster, but its velocity is different enough from that of the others to make its relation to the system unclear. The Great Dog Dwarf Galaxy may have associated open clusters, together with Dolidze twenty five and H18, and possibly AM 2. It is thought that the open clusters could have shaped because of the dwarf galaxy's gravity worrisome material within the galactic disk and stimulating star formation.

• Dispute

Several studies solid doubts on verity nature of this overdensity. Some analysis suggests that the path of stars is really a part of the crooked galactic skinny disk and thick disc population and not a results of the collision of the galaxy with a dwarf ellipsoidal galaxy. Investigation of the area in 2009 yielded only ten RR Lyrae variable stars that is in keeping with the whitish Way's halo and thick disk populations instead of a separate dwarf ellipsoid galaxy.

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