NGC 3561, also known as Arp 105, is a pair of

interacting galaxies Interacting galaxies (''colliding galaxies'') are galaxies whose gravitational fields result in a disturbance of one another. Major mergers occur between galaxies with similar amounts of mass, whereas minor mergers involve galaxies with masses ...

NGC 3561A and NGC 3561B within the galaxy cluster

Abell 1185 Abell 1185 is a galaxy cluster located in the constellation Ursa Major. It is approximately 400 million light-years away from Earth and spans one million light-years across. It is a member of the Leo Supercluster. One of its brightest galaxies i ...

Ursa Major Ursa Major, also known as the Great Bear, is a constellation in the Northern Sky, whose associated mythology likely dates back into prehistory. Its Latin name means "greater (or larger) bear", referring to and contrasting it with nearby Ursa M ...

. It was discovered by

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories and Crown Dependencies. * British national identity, the characteristics of British people and culture ...

astronomer

John Herschel Sir John Frederick William Herschel, 1st Baronet (; 7 March 1792 – 11 May 1871) was an English polymath active as a mathematician, astronomer, chemist, inventor and experimental photographer who invented the blueprint and did botanical work. ...

on 30 March 1827. Its common name is "the Guitar" and contains a small tidal

dwarf galaxy A dwarf galaxy is a small galaxy composed of about 1000 up to several billion stars, as compared to the Milky Way's 200–400 billion stars. The Large Magellanic Cloud, which closely orbits the Milky Way and contains over 30 billion stars, is so ...

known as Ambartsumian's Knot that is believed to be the remnant of the extensive tidal tail pulled out of one of the galaxies. One

supernova A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion ...

has been observed in NGC 3561A: SN 1953A (type unknown, mag. 16) was discovered by

Halton Arp Halton Christian "Chip" Arp (March 21, 1927 – December 28, 2013) was an American astronomer. He is remembered for his 1966 book ''Atlas of Peculiar Galaxies'', which catalogued unusual-looking galaxies and presented their images. Arp was als ...

on 16 April 1953.

Image gallery

File:Abell 1185 (NGC 3561 - Guitar).jpg, SDSS image of NGC 3561B (lower and brightest round spot of "the guitar") and NGC 3561A (oval shape above NGC 3561B). Ambartsumian's Knot is the blue speck below NGC 3561B.

References

External links

*
Abell 1185 and Ambartsumian's Knot
* Interacting galaxies Lenticular galaxies LINER galaxies 3561 06224

105 105 may refer to: *105 (number), the number * AD 105, a year in the 2nd century AD * 105 BC, a year in the 2nd century BC * 105 (telephone number), the emergency telephone number in Mongolia * 105 (MBTA bus), a Massachusetts Bay Transport Authority ...

Abell 1185 Ursa Major 033991 18270330 Discoveries by John Herschel {{lenticular-galaxy-stub