NGC 2936 | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Hydra |
Right ascension | 09h 37m 44.148s [1] |
Declination | +02° 45′ 38.95″ [1] |
Redshift | 0.02331±0.00013 [1] |
Heliocentric radial velocity | 6989±38 km/s [1] |
Galactocentric velocity | 6844±39 km/s [1] |
Distance | 352 Mly (108 Mpc) [1] |
Apparent magnitude (V) | 12.85 [1] |
Absolute magnitude (V) | -22.4 [1] |
Characteristics | |
Type | Irr [1] |
Size | 50.54 kpc [1] |
Other designations | |
NGC 2936, UGC 5130, MCG +01-25-006, PGC 27422 [2] |
NGC 2936, also known as the Penguin Galaxy or the Porpoise Galaxy, is an interacting spiral galaxy located at a distance of 326 million light years, [3] in the constellation Hydra. NGC 2936 is interacting with elliptical galaxy NGC 2937, located just beneath it. They were both discovered by Albert Marth on Mar 3, 1864. [4] To some astronomers, the galaxy looks like a penguin or a porpoise. [5] NGC 2936, NGC 2937, and PGC 1237172 are included in the Atlas of Peculiar Galaxies as Arp 142 in the category "Galaxy triplet".
On 20 June 2013, the Hubble Space Telescope examined and photographed NGC 2936. [5]
NGC 2936 once had a flat, spiral disk. The orbits of the galaxy's stars have been perturbed due to gravitational tidal interactions with NGC 2937. Gas from the center of NGC 2936 became compressed during the encounter with NGC 2937, which is shown as blue knots close to NGC 2937. The red dust that was inside the center of the galaxy has been mostly thrown out due to the collision. During the collision, gas coming from NGC 2936 triggered star formation. [6]
PGC 1237172, an unrelated bluish irregular galaxy or edge-on spiral galaxy, is located just off to the side of NGC 2936. It is located 230 million light years away, making it closer to the Earth than the NGC 2936 collision, and it happens to be located next to two unrelated stars from the Milky Way. [7]
In July 2024, NASA’s James Webb Space Telescope captured a vivid image of Arp 142, revealing intricate details of the interacting galaxies NGC 2936 and NGC 2937. [8] The observations showcased new star formation regions within the Penguin galaxy, enhanced by Webb’s near- and mid-infrared capabilities, [9] offering deeper insights into galactic evolution processes.
The brightest star in this galaxy is USNOA2 0900-06460021.
The M81 Group is a galaxy group in the constellations Ursa Major and Camelopardalis that includes the galaxies Messier 81 and Messier 82, as well as several other galaxies with high apparent brightnesses. The approximate center of the group is located at a distance of 3.6 Mpc, making it one of the nearest groups to the Local Group. The group is estimated to have a total mass of ×1012M☉. The M81 Group, the Local Group, and other nearby groups all lie within the Virgo Supercluster.
NGC 1 is an intermediate spiral galaxy of the morphological type Sbc, located in the constellation of Pegasus. It was discovered on 30 September 1861 by Heinrich d'Arrest.
NGC 772 is an unbarred spiral galaxy approximately 130 million light-years away in the constellation Aries.
Arp 240 is a pair of interacting spiral galaxies located in the constellation Virgo. The two galaxies are listed together as Arp 240 in the Atlas of Peculiar Galaxies. The galaxy on the right is known as NGC 5257, while the galaxy on the left is known as NGC 5258. Both galaxies are distorted by the gravitational interaction, and both are connected by a tidal bridge, as can be seen in images of these galaxies.
Arp 87 is a pair of interacting galaxies, NGC 3808A and NGC 3808B. They are situated in the Leo constellation. NGC 3808A, the brighter, is a peculiar spiral galaxy, while NGC 3808B is an irregular galaxy.
Mayall's Object is the result of two colliding galaxies located 500 million light years away within the constellation of Ursa Major. It was discovered by American astronomer Nicholas U. Mayall of the Lick Observatory on 13 March 1940, using the Crossley reflector. When first discovered, Mayall's Object was described as a peculiar nebula, shaped like a question mark. Originally theorized to represent a galaxy reacting with the intergalactic medium, it is now thought to represent the collision of two galaxies, resulting in a new object consisting of a ring-shaped galaxy with a tail emerging from it. It is thought that the collision between the two galaxies created a shockwave that initially drew matter into the center which then formed the ring.
The 2MASX J00482185−2507365 occulting pair is a pair of overlapping spiral galaxies found in the vicinity of NGC 253, the Sculptor Galaxy. Both galaxies are more distant than NGC 253, with the background galaxy, 2MASX J00482185−2507365, lying at redshift z=0.06, about 800 million light-years from Earth, and the foreground galaxy lying between NGC 253 and the background galaxy.
Arp 271 is a pair of similarly sized interacting spiral galaxies, NGC 5426 and NGC 5427, in the constellation of Virgo. It is not certain whether the galaxies are going to eventually collide or not. They will continue interacting for tens of millions of years, creating new stars as a result of the mutual gravitational attraction between the galaxies, a pull seen in the bridge of stars already connecting the two. Located about 130 million light-years away, the Arp 271 pair is about 130,000 light-years across. It was originally discovered in 1785 by William Herschel. It is speculated, that the Milky Way will undergo a similar collision in about five billion years with the neighbouring Andromeda Galaxy, which is currently located about 2.6 million light-years away.
NGC 6286 is an interacting spiral galaxy located in the constellation Draco. It is designated as Sb/P in the galaxy morphological classification scheme and was discovered by the American astronomer Lewis A. Swift on 13 August 1885. NGC 6286 is located at about 252 million light years away from Earth. NGC 6286 and NGC 6285 form a pair of interacting galaxies, with tidal distortions, categorized as Arp 293 in the Arp Atlas of Peculiar Galaxies.
NGC 1741 is a distant pair of interacting galaxies in the Eridanus constellation. It was discovered on 6 January 1878 by French astronomer Édouard Stephan. As a result of the collision, the galaxies are in a rapid starburst phase. The galaxies are classed as Wolf–Rayet galaxies due to their high content of rare Wolf–Rayet stars.
NGC 4647 is an intermediate spiral galaxy estimated to be around 63 million light-years away in the constellation of Virgo. It was discovered by astronomer William Herschel on March 15, 1784. NGC 4647 is listed along with Messier 60 as being part of a pair of galaxies called Arp 116; their designation in Halton Arp's Atlas of Peculiar Galaxies. The galaxy is located on the outskirts of the Virgo Cluster.
PGC 44691 is a spiral galaxy located about 350 million light-years away in the constellation Coma Berenices. It belongs to a galaxy cluster known as the Coma Cluster. In 1994, the Hubble Space Telescope observed PGC 44691 and the nearby elliptical galaxy NGC 4881 to infer the distance to the Coma Cluster.
NGC 6040 is a spiral galaxy located about 550 million light-years away in the constellation Hercules. NGC 6040 was discovered by astronomer Édouard Stephan on June 27, 1870. NGC 6040 is interacting with the lenticular galaxy PGC 56942. As a result of this interaction, NGC 6040's southern spiral arm has been warped in the direction toward PGC 56942. NGC 6040 and PGC 56942 are both members of the Hercules Cluster.
NGC 5468 is an intermediate spiral galaxy located in the constellation Virgo. It is located at a distance of about 140 million light-years from Earth, which, given its apparent dimensions, means that NGC 5468 is about 110,000 light-years across. It was discovered by William Herschel on March 5, 1785.
NGC 541 is a lenticular galaxy located in the constellation Cetus. It is located at a distance of about 230 million light years from Earth, which, given its apparent dimensions, means that NGC 541 is about 130,000 light years across. It was discovered by Heinrich d'Arrest on October 30, 1864. It is a member of the Abell 194 galaxy cluster and is included in the Atlas of Peculiar Galaxies in the category galaxies with nearby fragments. NGC 541 is a radio galaxy of Fanaroff–Riley class I, also known as 3C 40A.
NGC 6621 is an interacting spiral galaxy in the constellation Draco. It lies at a distance of circa 260 million light-years. NGC 6621 interacts with NGC 6622, with their closest approach having taken place about 100 million years before the moment seen now. The pair was discovered by Edward D. Swift and Lewis A. Swift on June 2, 1885. Originally NGC 6621 was assigned to the southeast galaxy, but now it refers to the northern one. NGC 6621 and NGC 6622 are included in the Atlas of Peculiar Galaxies as Arp 81 in the category "spiral galaxies with large high surface brightness companions".
NGC 1356 is a barred spiral galaxy located in the southern constellation of Horologium. It was discovered by English astronomer John Herschel on Dec 23, 1837.
NGC 6365 is a pair of spiral galaxies in the constellation Draco. It consists of two galaxies, PGC 60174 to the south, and PGC 60171 to the north. These two galaxies are also designated respectively by the NASA/IPAC database as NGC 6365A and NGC 6365B. This pair of galaxies was discovered by German astronomer Lewis Swift in 1884.
NGC 2935 is a large intermediate spiral galaxy located in the constellation Hydra. Its speed relative to the cosmic microwave background is 2,601 ± 23 km/s, which corresponds to a Hubble distance of 38.4 ± 2.7 Mpc. NGC 2935 was discovered by German-British astronomer William Herschel in 1786.
NGC 2937 is an elliptical galaxy located in the constellation Hydra. Its velocity relative to the cosmic microwave background is 105.1 ± 7.4 km/s, which corresponds to a Hubble distance of 105.1 ± 7.4 Mpc. NGC 2937 was discovered by German astronomer Albert Marth in 1864.