NGC 1023
Galaxy NGC 1023 |
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NGC 1023 & (very faint) adjacent to the left PGC 10139 | |
AladinLite | |
Constellation | Perseus |
Position equinox : J2000.0 , epoch : J2000.0 |
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Right ascension | 02 h 40 m 24.0 s |
declination | + 39 ° 03 ′ 48 ″ |
Appearance | |
Morphological type | SB (rs) 0- |
Brightness (visual) | 9.5 likes |
Brightness (B-band) | 10.5 mag |
Angular expansion | 7.4 ′ × 2.5 ′ |
Position angle | 87 ° |
Surface brightness | 12.7 mag / arcmin² |
Physical data | |
Affiliation |
NGC-1023 group LGG 70 |
Redshift | 0.002125 ± 0.000013 |
Radial velocity | (637 ± 4) km / s |
Stroke distance v rad / H 0 |
(34 ± 2) x 10 6 ly (10.32 ± 0.73) Mpc |
Absolute brightness | −19.9 mag |
diameter | approx. 72,000 ly |
history | |
discovery | Wilhelm Herschel |
Discovery date | October 18, 1786 |
Catalog names | |
NGC 1023 • UGC 2154 • PGC 10123 • CGCG 523-83 • MCG + 06-06-073 • 2MASX J02402401 + 3903477 • Arp 135 • VV 1039 • GC 575 • H I 156 • h 242 • GALEX ASC J024023.99 + 390347.4 • LDCE 160 NED013 |
NGC 1023 is a galaxy in the constellation Perseus in the northern sky . The classification of the object fluctuates because of the strong flattening between a spindle-shaped Hubble type S0 and an extremely flattened elliptical galaxy (E7). It is estimated to be 34 million light years from the Milky Way and around 60,000 light years in diameter.
NGC 1023 belongs to the NGC 1023 group named after it , the group includes the galaxies NGC 891 , NGC 925 , NGC 949 , NGC 959 , NGC 1003 , NGC 1058 and IC 239 .
Due to the rotation of NGC 1023, scientists have calculated that there must be a supermassive black hole of around 40 to 60 million solar masses inside this galaxy , otherwise the centrifugal forces would tear the galaxy apart.
The galaxy consists predominantly of about ten billion year old stars , with only a small proportion of a young population in the outer areas and, due to a lack of supplies of hydrogen gas , no star-forming regions . Nevertheless, the galaxy is surrounded by a large supply of approx. 1.5 billion solar masses of neutral hydrogen, which surrounds it in two rings. This gas could have come from a small companion, the dwarf galaxy PGC 10139 . However, it apparently has not yet reached the main galaxy properly, because no new star formation regions that could be associated with the gas clouds appear.
Together, this pair of galaxies is listed as Arp 135 in the Arp catalog. Halton Arp organized his catalog of unusual galaxies into groups according to purely morphological criteria. This galaxy belongs to the class of elliptical galaxies with nearby fragments ( Arp catalog ).
The object was discovered on October 18, 1786 by the German-British astronomer Wilhelm Herschel .
NGC 1023 group ( LGG 70 )
Galaxy | Alternative name | Distance / million Lj |
---|---|---|
NGC 1023 | PGC 10123 | 34 |
PGC 10139 | NGC 1023 A | 38 |
NGC 1003 | PGC 10052 | 33 |
PGC 9759 | UGC 2034 | 31 |
IC 239 | PGC 9899 | 46 |
PGC 10133 | 36 | |
PGC 10143 | 46 | |
PGC 10169 | 32 |
Web links
- SIMBAD Astronomical Database
- NGC 1023 in Black Hole Encyclopedia
- Supermassive Black Hole in the Galaxy NGC 1023
- ARP ATLAS OF PECULIAR GALAXIES
- Seligman Arp
literature
- Jeff Kanipe and Dennis Webb: The Arp Atlas of Peculiar Galaxies - A Chronicle and Observer's Guide , Richmond 2006, ISBN 978-0-943396-76-7