Antennae Galaxies | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Corvus [1] |
Right ascension | 12h 01m 53.0s / 12h 01m 53.6s [2] |
Declination | −18° 52′ 10″ / −18° 53′ 11″ [2] |
Redshift | 1642 ± 12 / 1641 ± 9 km/s [2] |
Distance | 45 Mly / 65 Mly |
Apparent magnitude (V) | 11.2 / 11.1 [2] |
Characteristics | |
Type | SB(s)m pec / SA(s)m pec [2] |
Size | 500,000 ly (150 kpc) [3] [a] |
Apparent size (V) | 5.2′ × 3.1′ / 3.1′ × 1.6′ [2] |
Notable features | Interacting galaxies |
Other designations | |
Ringtail Galaxy, [2] NGC 4038 / 4039, [2] PGC 37967 / 37969, Arp 244, [2] Caldwell 60/61, UGCA 264/265 [2] |
The Antennae Galaxies (also known as NGC 4038/NGC 4039 or Caldwell 60/Caldwell 61) are a pair of interacting galaxies in the constellation Corvus. They are currently going through a starburst phase, in which the collision of clouds of gas and dust, with entangled magnetic fields, causes rapid star formation. They were discovered by William Herschel in 1785. [4]
The Antennae Galaxies are undergoing a galactic collision. Located in the NGC 4038 group with five other galaxies, these two galaxies are known as the Antennae Galaxies because the two long tails of stars, gas and dust ejected from the galaxies as a result of the collision resemble an insect's antennae.
The nuclei of the two galaxies are joining to become one giant galaxy. Most galaxies probably undergo at least one significant collision in their lifetimes. This is likely the future of our Milky Way when it collides with the Andromeda Galaxy. This collision and merger sequence (the Toomre sequence) for galaxy evolution was developed in part by successfully modeling the Antennae Galaxies' "antennae" in particular.
A recent study finds that these interacting galaxies are less remote from the Milky Way than previously thought—at 45 million light-years instead of 65 million light-years. [5]
They are located 0.25° north of 31 Crateris and 3.25° southwest of Gamma Corvi. [6]
The Antennae galaxies also contain a relatively young collection of massive globular clusters that were possibly formed as a result of the collision between the two galaxies. [7] The young age of these clusters is in contrast to the average age of most known globular clusters (which are around 12 billion years old), with the formation of the globulars likely originating from shockwaves, generated by the collision of the galaxies, compressing large, massive molecular clouds. The densest regions of the collapsing and compressing clouds are believed to be the birthplace of the clusters.
Five supernovae have been observed in NGC 4038.
This section needs additional citations for verification .(October 2020) |
About 1.2 billion years ago, the Antennae were two separate galaxies. [16] NGC 4038 was a barred spiral galaxy and NGC 4039 was a spiral galaxy. 900 million years ago, the Antennae began to approach one another, looking similar to NGC 2207 and IC 2163. 600 million years ago, the Antennae passed through each other, looking like the Mice Galaxies. 300 million years ago, the Antennae's stars began to be released from both galaxies. Today the two streamers of ejected stars extend far beyond the original galaxies, resulting in the antennae shape. [17]
Within 400 million years, the Antennae's nuclei will collide and become a single core with stars, gas, and dust around it. [18] Observations and simulations of colliding galaxies (e.g., by Alar Toomre) suggest that the Antennae Galaxies will eventually form an elliptical galaxy. [16] [ page needed ]
Areas containing large amounts of neon (Ne), magnesium (Mg), and silicon (Si) were found when the Chandra X-ray Observatory analyzed the Antennae Galaxies. Heavy elements such as these are necessary in order for planets that may contain life (as we know it) to form. The clouds imaged contain 16 times as much magnesium and 24 times as much silicon as the Sun.
Messier 100 is a grand design intermediate spiral galaxy in the southern part of the mildly northern Coma Berenices. It is one of the brightest and largest galaxies in the Virgo Cluster and is approximately 55 million light-years from our galaxy, its diameter being 107,000 light years, and being about 60% as large. It was discovered by Pierre Méchain in 1781 and 29 days later seen again and entered by Charles Messier in his catalogue "of nebulae and star clusters". It was one of the first spiral galaxies to be discovered, and was listed as one of fourteen spiral nebulae by Lord William Parsons of Rosse in 1850. NGC 4323 and NGC 4328 are satellite galaxies of M100; the former is connected with it by a bridge of luminous matter.
NGC 6240, also known as the Starfish Galaxy, is a nearby ultraluminous infrared galaxy (ULIRG) in the constellation Ophiuchus. It was discovered by French astronomer Édouard Stephan on 12 July 1871.
The Pinwheel Galaxy is a face-on, unbarred, and counterclockwise spiral galaxy located 21 million light-years from Earth in the constellation Ursa Major. It was discovered by Pierre Méchain in 1781 and was communicated that year to Charles Messier, who verified its position for inclusion in the Messier Catalogue as one of its final entries.
Messier 61 is an intermediate barred spiral galaxy in the Virgo Cluster of galaxies. It was first discovered by Barnaba Oriani on May 5, 1779, six days before Charles Messier discovered the same galaxy. Messier had observed it on the same night as Oriani but had mistaken it for a comet. Its distance has been estimated to be 45.61 million light years from the Milky Way Galaxy. It is a member of the M61 Group of galaxies, which is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster.
Centaurus A is a galaxy in the constellation of Centaurus. It was discovered in 1826 by Scottish astronomer James Dunlop from his home in Parramatta, in New South Wales, Australia. There is considerable debate in the literature regarding the galaxy's fundamental properties such as its Hubble type and distance. It is the closest radio galaxy to Earth, as well as the closest BL Lac object, so its active galactic nucleus has been extensively studied by professional astronomers. The galaxy is also the fifth-brightest in the sky, making it an ideal amateur astronomy target. It is only visible from the southern hemisphere and low northern latitudes.
NGC 3184, the Little Pinwheel Galaxy, is a spiral galaxy approximately 40 million light-years away in the constellation Ursa Major. Its name comes from its resemblance to the Pinwheel Galaxy. It was discovered on 18 March 1787 by German-British astronomer William Herschel. It has two HII regions named NGC 3180 and NGC 3181.
NGC 6745 is an irregular galaxy about 206 million light-years away in the constellation Lyra. It was discovered by French astronomer Édouard Stephan on 24 July 1879.
NGC 2442 and NGC 2443 are two parts of a single intermediate spiral galaxy, commonly known as the Meathook Galaxy or the Cobra and Mouse. It is about 50 million light-years away in the constellation Volans. It was discovered by Sir John Herschel on December 23, 1834 during his survey of southern skies with a 18.25 inch diameter reflecting telescope from an observatory he set up in Cape Town, South Africa. Associated with this galaxy is HIPASS J0731-69, a cloud of gas devoid of any stars. It is likely that the cloud was torn loose from NGC 2442 by a companion.
NGC 3310 is a grand design spiral galaxy in the constellation Ursa Major. It is a starburst galaxy and it is likely that NGC 3310 collided with one of its satellite galaxies about 100 million years ago, triggering widespread star formation. It is thought to be located approximately 46 million light-years away from the Earth, and is thought to be about 22,000 light-years wide.
NGC 6744 is an intermediate spiral galaxy in the constellation Pavo (Peacock). Its velocity with respect to the cosmic microwave background is 802 ± 3 km/s, which corresponds to a Hubble distance of 38.6 ± 2.7 Mly (11.82 ± 0.83 Mpc). However, 21 non redshift measurements give a distance of 23.63 ± 1.68 Mly (7.244 ± 0.514 Mpc). It was discovered on 30 June 1826 by Scottish astronomer James Dunlop, observing from Parramatta, Australia.
NGC 2207 and IC 2163 are a pair of colliding spiral galaxies about 80 million light-years away in the constellation Canis Major. Both galaxies were discovered by John Herschel in 1835.
NGC 4027 is a barred spiral galaxy approximately 83 million light-years away in the constellation Corvus. It is also a peculiar galaxy because one of its spiral arms goes out more than the other. This is probably due to a galactic collision in NGC 4027's past.
NGC 5253 is an irregular galaxy in the constellation Centaurus. It was discovered by William Herschel on 15 March 1787.
Arp 299 is a pair of colliding galaxies approximately 134 million light-years away in the constellation Ursa Major. Both of the galaxies involved in the collision are barred irregular galaxies. NGC 3690 was discovered on 18 March 1790 by German-British astronomer William Herschel.
NGC 4622, also known as the Backward Galaxy, is a face-on unbarred spiral galaxy with a very prominent ring structure located in the constellation Centaurus. The galaxy is a member of the Centaurus Cluster.
NGC 4790 is a barred spiral galaxy located in the constellation of Virgo. Its velocity with respect to the cosmic microwave background is 1679 ± 24 km/s, which corresponds to a Hubble distance of 80.8 ± 5.8 Mly (24.76 ± 1.77 Mpc). In addition, six non-redshift measurements give a distance of 74.75 ± 4.07 Mly (22.917 ± 1.249 Mpc). It was discovered on 25 March 1786 by German-British astronomer William Herschel.
NGC 3198, also known as Herschel 146 is a barred spiral galaxy in the constellation Ursa Major. It was discovered by William Herschel on 15 January 1788. NGC 3198 is located in the Leo Spur, which is part of the Virgo Supercluster, and is approximately 47 million light years away.
NGC 6951 is a barred spiral galaxy located in the constellation Cepheus. It is located at a distance of about 75 million light-years from Earth, which, given its apparent dimensions, means that NGC 6951 is about 100,000 light-years across. It was discovered by Jérôme Eugène Coggia in 1877 and independently by Lewis Swift in 1878.
NGC 4589 is an elliptical galaxy located in the Draco constellation. It was discovered by German-British astronomer William Herschel on November 22, 1797. This galaxy lies at a distance of 73.0 million light-years (22.39 Mpc) from the Milky Way, and is receding with a heliocentric radial velocity of 2,002 km/s. It is known by its designations PGC 42139 or UGC 7797.
NGC 5514 is a pair of merging disk galaxies in the northern constellation of Boötes. They were discovered by German astronomer Heinrich d'Arrest on April 26, 1865. The galaxies are located at an estimated distance of 347 million light-years. The morphology of the system is similar to the Antennae Galaxies, NGC 4038/NGC 4039. A distinct tail extends to the east for an angular distance of 1.5′. There is a fainter tail extending a comparable distance to the west. This galaxy pair likely forms a small group with the nearby spiral galaxy NGC 5519.