Messier 82 (also known as NGC 3034, Cigar Galaxy or M82) is a starburst galaxy approximately 12 million light-years away in the constellation Ursa Major. It is the second-largest member of the M81 Group, with the D25 isophotal diameter of 12.52 kiloparsecs (40,800 light-years).It is about five times more luminous than the Milky Way and its central region is about one hundred times more luminous The starburst activity is thought to have been triggered by interaction with neighboring galaxy M81. As one of the closest starburst galaxies to Earth, M82 is the prototypical example of this galaxy type. SN 2014J, a Type Ia supernova, was discovered in the galaxy on 21 January 2014.In 2014, in studying M82, scientists discovered the brightest pulsar yet known, designated M82 X-2.
In November 2023, a gamma-ray burst was observed in M82, which was determined to have come from a magnetar, the first such event detected outside the Milky Way (and only the fourth such event ever detected).
Discovery
M82, with M81, was discovered by Johann Elert Bode in 1774; he described it as a “nebulous patch”, this one about 3⁄4 degree away from the other, “very pale and of elongated shape”. In 1779, Pierre Méchain independently rediscovered both objects and reported them to Charles Messier, who added them to his catalog.
Structure
M82 was believed to be an irregular galaxy. In 2005, however, two symmetric spiral arms were discovered in near-infrared (NIR) images of M82. The arms were detected by subtracting an axisymmetric exponential disk from the NIR images. Even though the arms were detected in NIR images, they are bluer than the disk. The arms had been missed due to M82’s high disk surface brightness, the nearly edge-on view of this galaxy (~80°),and obscuration by a complex network of dusty filaments in its optical images. These arms emanate from the ends of the NIR bar and can be followed for the length of three disc scales. Assuming that the northern part of M82 is nearer to us, as most of the literature does, the observed sense of rotation implies trailing arms.
Image Details
Location : Hampshire UK
Telescope : Celestron Edge 8HD
Camera : ZWO 533mm pro
Mount : Skywatcher EQ6-R pro tunned
Filters : Antilia LRGB crystal clear filters
R = 23*120, B=46*120, G=31*120, L=23*120
Total intergration 3.06 hours
Software :Pixinsight Ripley
M82 Cigar Galaxy Annotated