NGC 2293

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NGC 2293
NGC 2292 and NGC 2293 p2032a.png
NGC 2292 (right) and NGC 2293 (left) by the Hubble Space Telescope
Observation data (J2000 epoch)
Constellation Canis Major
Right ascension 06h 47m 42.9s [1]
Declination −26° 45 16 [1]
Redshift 0.006795 ± 0.000020 [1]
Helio radial velocity 2037 ± 6 km/s [1]
Distance 107 ± 49 Mly (32.9 ± 15.0 Mpc) [1]
Apparent magnitude  (V)11.2 [2]
Characteristics
Type SAB(s)0+ pec [1]
Apparent size  (V)4.2 × 3.3 [1]
Notable featuresInteracts with NGC 2292
Other designations
ESO 490-IG 049, VV 178a, MCG -04-16-023, PGC 19619 [1]

NGC 2293 is a lenticular galaxy located in the constellation Canis Major. It is located at a distance of circa 100 million light years from Earth, which, given its apparent dimensions, means that NGC 2293 is about 160,000 light years across. It was discovered by John Herschel on January 20, 1835. [3] NGC 2293 forms a pair with NGC 2292 and has an HI ring that surrounds both galaxies.

Contents

Characteristics

NGC 2293 is a lenticular galaxy with hints of a spiral structure. The old stars that make it give the galaxy an orange color. [4] Located 0.8 arcminutes away from NGC 2292 lies NGC 2293. Both galaxies appear to share a common envelope and a complete ring of neutral hydrogen gas (HI) has been found to encircle both galaxies. The ring apparently has a color change to the southwestern view, that has been attributed to the presence of star formation. On the other hand, there is a marked absence of HI near the centre of the two galaxies. [5] The total HI mass is 0.75×109 M. [5] [6]

It is possible that the ring is the result of an ongoing merger between the two galaxies, that would result in a giant elliptical galaxy. [5] Various models have been suggested for the formation of the ring. The most likely model is the collision between one of the two galaxies and one more galaxy that swept gas away, with the star formation region on the ring been created by a density wave or it is a population that was stripped by the intruder galaxy. [5] It has not been ruled out that the positioning is an projection effect of two galaxies separated by a few million light years. [5]

Based on far infrared observations there is an extensive amount of cold dust at the pair, with temperature 13 K, which is lower than dust temperatures found in spiral and interacting galaxies. The temperature indicates however that it is not of primordial origin. [6]

Nearby galaxies

NGC 2292/2293 pair belongs to a galaxy group known as LGG 138. Other members of the group are the spiral galaxy NGC 2280, NGC 2295, ESO 490−G010 and ESO 490−G045. Because of its large angular diameter, about one degree, the group was identified when redshift information were available, by Garcia et al. in 1993. [7]

Related Research Articles

<span class="mw-page-title-main">Hubble sequence</span> Galaxy morphological classification scheme advocated by Edwin Hubble

The Hubble sequence is a morphological classification scheme for galaxies published by Edwin Hubble in 1926. It is often colloquially known as the Hubble tuning-fork diagram because the shape in which it is traditionally represented resembles a tuning fork. It was invented by John Henry Reynolds and Sir James Jeans.

<span class="mw-page-title-main">Elliptical galaxy</span> Spherical or ovoid mass of stars

An elliptical galaxy is a type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image. They are one of the four main classes of galaxy described by Edwin Hubble in his Hubble sequence and 1936 work The Realm of the Nebulae, along with spiral and lenticular galaxies. Elliptical (E) galaxies are, together with lenticular galaxies (S0) with their large-scale disks, and ES galaxies with their intermediate scale disks, a subset of the "early-type" galaxy population.

<span class="mw-page-title-main">Lenticular galaxy</span> Class of galaxy between an elliptical galaxy and a spiral galaxy

A lenticular galaxy is a type of galaxy intermediate between an elliptical and a spiral galaxy in galaxy morphological classification schemes. It contains a large-scale disc but does not have large-scale spiral arms. Lenticular galaxies are disc galaxies that have used up or lost most of their interstellar matter and therefore have very little ongoing star formation. They may, however, retain significant dust in their disks. As a result, they consist mainly of aging stars. Despite the morphological differences, lenticular and elliptical galaxies share common properties like spectral features and scaling relations. Both can be considered early-type galaxies that are passively evolving, at least in the local part of the Universe. Connecting the E galaxies with the S0 galaxies are the ES galaxies with intermediate-scale discs.

<span class="mw-page-title-main">NGC 5866</span> Galaxy in the constellation Draco

NGC 5866 is a relatively bright lenticular galaxy in the constellation Draco. NGC 5866 was most likely discovered by Pierre Méchain or Charles Messier in 1781, and independently found by William Herschel in 1788. Measured orbital velocities of its globular cluster system imply that dark matter makes up only 34±45% of the mass within 5 effective radii, a notable paucity.

<span class="mw-page-title-main">NGC 3115</span> Galaxy in the constellation Sextans

NGC 3115 is a field lenticular (S0) galaxy in the constellation Sextans. The galaxy was discovered by William Herschel on February 22, 1787. At about 32 million light-years away from Earth, it is several times bigger than the Milky Way. It is a lenticular (S0) galaxy because it contains a disk and a central bulge of stars, but without a detectable spiral pattern. NGC 3115 is seen almost exactly edge-on, but was nevertheless mis-classified as elliptical. There is some speculation that NGC 3115, in its youth, was a quasar.

<span class="mw-page-title-main">NGC 6822</span> Galaxy in the constellation Sagittarius

NGC 6822 is a barred irregular galaxy approximately 1.6 million light-years away in the constellation Sagittarius. Part of the Local Group of galaxies, it was discovered by E. E. Barnard in 1884, with a six-inch refractor telescope. It is the closest non-satellite galaxy to the Milky Way, but lies just outside its virial radius. It is similar in structure and composition to the Small Magellanic Cloud. It is about 7,000 light-years in diameter.

<span class="mw-page-title-main">NGC 1097</span> Galaxy in the constellation Fornax

NGC 1097 is a barred spiral galaxy about 45 million light years away in the constellation Fornax. It was discovered by William Herschel on 9 October 1790. It is a severely interacting galaxy with obvious tidal debris and distortions caused by interaction with the companion galaxy NGC 1097A.

<span class="mw-page-title-main">NGC 2787</span> Galaxy in the constellation Ursa Major

NGC 2787 is a barred lenticular galaxy approximately 24 million light-years away in the northern constellation of Ursa Major. It was discovered on December 3, 1788 by German-born astronomer William Herschel. J. L. E. Dreyer described it as, "bright, pretty large, a little extended 90°, much brighter middle, mottled but not resolved, very small (faint) star involved to the southeast". The visible galaxy has an angular size of 2′.5 × 1′.5 and an apparent visual magnitude of 11.8.

<span class="mw-page-title-main">Polar-ring galaxy</span> Type of galaxy in which an outer ring of gas and stars rotates over the poles of the galaxy

A polar-ring galaxy is a type of galaxy in which an outer ring of gas and stars rotates over the poles of the galaxy. These polar rings are thought to form when two galaxies gravitationally interact with each other. One possibility is that a material is tidally stripped from a passing galaxy to produce the polar ring seen in the polar-ring galaxy. The other possibility is that a smaller galaxy collides orthogonally with the plane of rotation of the larger galaxy, with the smaller galaxy effectively forming the polar-ring structure.

<span class="mw-page-title-main">NGC 4622</span> Galaxy in the constellation Centaurus

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<span class="mw-page-title-main">NGC 1808</span> Galaxy in the constellation Columba

NGC 1808 is a barred spiral galaxy located in the southern constellation of Columba, about two degrees to the south and east of Gamma Caeli. It was discovered by Scottish astronomer James Dunlop, who described it as a "faint nebula". The galaxy is a member of the NGC 1808 group, which is part of the larger Dorado Group.

<span class="mw-page-title-main">NGC 1553</span> Galaxy in the constellation Dorado

NGC 1553 is a prototypical lenticular galaxy in the constellation Dorado. It is the second brightest member of the Dorado Group of galaxies. British astronomer John Herschel discovered NGC 1553 on December 5, 1834 using an 18.7 inch reflector.

<span class="mw-page-title-main">NGC 7013</span> Spiral or lenticular galaxy in the constellation Cygnus

NGC 7013 is a relatively nearby spiral or lenticular galaxy estimated to be around 37 to 41.4 million light-years away from Earth in the constellation of Cygnus. NGC 7013 was discovered by English astronomer William Herschel on July 17, 1784 and was also observed by his son, astronomer John Herschel on September 15, 1828.

<span class="mw-page-title-main">NGC 2336</span> Galaxy in the constellation Camelopardalis

NGC 2336 is a Barred spiral galaxy located in the constellation Camelopardalis. It is located at a distance of circa 100 million light years from Earth, which, given its apparent dimensions, means that NGC 2336 is about 200,000 light years across. It was discovered by Wilhelm Tempel in 1876.

<span class="mw-page-title-main">NGC 2280</span> Spiral galaxy in the constellation Canis Major

NGC 2280 is a spiral galaxy located in the constellation Canis Major. It is located at a distance of circa 75 million light years from Earth, which, given its apparent dimensions, means that NGC 2280 is about 135,000 light years across. It was discovered by John Herschel on February 1, 1835. One supernova has been observed in NGC 2280, SN 2001fz, a type II supernova discovered by the Beijing Astronomical Observatory Supernova Survey on November 15, 2001. It had a peak magnitude of 17.4.

<span class="mw-page-title-main">NGC 541</span> Galaxy in the constellation Cetus

NGC 541 is a lenticular galaxy located in the constellation Cetus. It is located at a distance of circa 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.

<span class="mw-page-title-main">NGC 6907</span> Galaxy in the constellation Capricornus

NGC 6907 is a spiral galaxy located in the constellation Capricornus. It is located at a distance of about 120 million light years from Earth, which, given its apparent dimensions, means that NGC 6907 is about 115,000 light years across. It was discovered by William Herschel on July 12, 1784. The total infrared luminosity of the galaxy is 1011.03 L, and thus it is categorised as a luminous infrared galaxy.

<span class="mw-page-title-main">NGC 3585</span> Galaxy in the constellation Hydra

NGC 3585 is an elliptical or a lenticular galaxy located in the constellation Hydra. It is located at a distance of circa 60 million light-years from Earth, which, given its apparent dimensions, means that NGC 3585 is about 80,000 light years across. It was discovered by William Herschel on December 9, 1784.

<span class="mw-page-title-main">NGC 4299</span> Spiral galaxy in the constellation Virgo

NGC 4299 is a featureless spiral galaxy located about 55 million light-years away in the constellation Virgo. It was discovered by astronomer William Herschel on March 15, 1784 and is a member of the Virgo Cluster.

<span class="mw-page-title-main">NGC 4324</span> Galaxy in the constellation of Virgo

NGC 4324 is a lenticular galaxy located about 85 million light-years away in the constellation Virgo. It was discovered by astronomer Heinrich d'Arrest on March 4, 1862. NGC 4324 has a stellar mass of 5.62 × 1010M, and a baryonic mass of 5.88 × 1010M. The galaxy's total mass is around 5.25 × 1011M. NGC 4324 is notable for having a ring of star formation surrounding its nucleus. It was considered a member of the Virgo II Groups until 1999, when its distance was recalculated and it was placed in the Virgo W Group.

References

  1. 1 2 3 4 5 6 7 8 "NASA/IPAC Extragalactic Database". Results for NGC 2293. Retrieved 2016-01-18.
  2. "Revised NGC Data for NGC 2293". spider.seds.org. Retrieved 25 November 2018.
  3. Seligman, Courtney. "NGC 2293 (= PGC 19531)". Celestial Atlas. Retrieved 19 November 2018.
  4. "Hubble finds "Greater Pupkin" galaxy pair". HubbleSite.org. 29 October 2020. Retrieved 3 November 2020.
  5. 1 2 3 4 5 Barnes, David G. (1999). "A New H I Ring: LGG 138". Publications of the Astronomical Society of Australia. 16 (1): 77–83. Bibcode:1999PASA...16...77B. doi: 10.1071/AS99077 .
  6. 1 2 Stickel, M.; Barnes, D.; Krause, O. (November 2005). "Extended very cold dust in the interacting HI ring galaxy pair NGC 2293 / 2292". Astronomy & Astrophysics. 443 (2): 373–381. Bibcode:2005A&A...443..373S. doi: 10.1051/0004-6361:20053227 .
  7. Barnes, D. G.; Webster, R. L. (July 2001). "A study of neutral hydrogen in five small galaxy groups". Monthly Notices of the Royal Astronomical Society. 324 (4): 859–876. Bibcode:2001MNRAS.324..859B. doi: 10.1046/j.1365-8711.2001.04273.x .