NGC 945 | |
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![]() NGC 945 (right) and NGC 948 (left) | |
Observation data (J2000 epoch) | |
Right ascension | 02h 28m 36s |
Declination | -10° 32′ 20″ |
Apparent magnitude (B) | 1202h 28m 36s |
Surface brightness | 23.01 mag/arcsec2 |
NGC 945 is a barred spiral galaxy in the constellation Cetus. [1] It is located south of the celestial equator. It is estimated to be 200 million light-years from the Milky Way and about 135,000 light-years in diameter. [2] Together with NGC 948, it forms a gravitationally bound pair of galaxies. In the same area of the sky there are, among other things: the galaxies NGC 942, NGC 943, NGC 950, IC 230. The Type Ib supernova SN 1998dt was observed here. The object was discovered by astronomer William Herschel on November 28, 1785. It is within close proximity to NGC 948.
NGC 948 is a spiral galaxy located extremely close to NGC 945. [3] Its speed relative to the cosmic microwave background is 4,259 ± 17 km/s, [4] which corresponds to a Hubble distance of 62.8 ± 4.4 Mpc (~205 million ly). NGC 948 was discovered by American astronomer Lewis Swift in 1886. The luminosity class of NGC 948 is III and it has a broad HI line. With a surface brightness equal to 14.17 mag/am2, NGC 948 is classified as a low surface brightness galaxy (LSB). [5]
The supernova SN 1998dt was discovered in NGC 945 on September 1, 1998, by T. Shefler of the University of California at Berkeley [6] as part of the LOSS (Lick Observatory Supernova Search) program at the Lick observatory. This supernova is classified as a type Ib. [7]
NGC 945 is the brightest galaxy in a group of at least 7 members that bears its name. [8] The other six galaxies in the NGC 945 group are NGC 948, NGC 950, NGC 977, MCG -2-7-20, MCG -2-7-32 and MCG -2-7-337. [8]
NGC 7331, also known as Caldwell 30, is an unbarred spiral galaxy about 40 million light-years (12 Mpc) away in the constellation Pegasus. It was discovered by William Herschel in 1784. NGC 7331 is the brightest galaxy in the field of a visual grouping known as the NGC 7331 Group of galaxies. In fact, the other members of the group, NGC 7335, 7336, 7337 and 7340, lie far in the background at distances of approximately 300–350 million light years.
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 2770 is a spiral galaxy in the northern constellation of Lynx, near the northern constellation border with Cancer. It was discovered by German-born astronomer William Herschel on December 7, 1785. J. L. E. Dreyer described it as, "faint, large, much extended 150°, mottled but not resolved, 2 stars to north". NGC 2770 was the target for the first binocular image produced by the Large Binocular Telescope.
NGC 6118 is a grand design spiral galaxy located 83 million light-years away in the constellation Serpens. It measures roughly 110,000 light-years across; about the same as our own galaxy, the Milky Way. Its shape is classified as "SA(s)cd," meaning that it is unbarred and has several rather loosely wound spiral arms. The large numbers of bright bluish knots are active star-forming regions where some very luminous and young stars can be perceived.
NGC 157 is an intermediate spiral galaxy in the constellation of Cetus, positioned about 4° east of the star Iota Ceti. This galaxy can be viewed from suburban skies using a moderate-sized telescope. It was discovered on December 13, 1783 by William Herschel. The compiler of the New General Catalogue, John Louis Emil Dreyer noted that NGC 157 was "pretty bright, large, extended, between 2 considerably bright stars". It is a relatively isolated galaxy; the nearest other galaxy of comparable luminosity lies at a separation of 4.2 Mly (1.3 Mpc).
NGC 991 is an intermediate spiral galaxy the constellation Cetus. This galaxy was discovered by astronomer William Herschel in 1785.
NGC 1325 is a flocculent spiral galaxy situated in the constellation of Eridanus. Located about 75 million light years away, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. It was discovered by William Herschel on 19 December 1799.
NGC 3435 is a barred spiral galaxy located about 235 million light-years from the Milky Way, and is about 125 000 light-years across. It can be found in the constellation Ursa Major. It was discovered on 9 April 1793 by astronomer William Herschel.
NGC 7329 is a large barred spiral galaxy located in the constellation Tucana. NGC 7329 was discovered by British astronomer John Herschel in 1835.
NGC 3110, known as NGC 3122 and NGC 3518 is an active spiral galaxy in the Constellation Sextans. It contains extensive Hubble-type Sb star-forming regions, and is located south of the celestial equator. It is estimated to be 218 million light-years from the Milky Way and has a diameter of around 100,000 ly. Together with PGC 29184 it forms a gravitationally bound galaxy pair. Located in the same area of the sky is the galaxy IC 589.
NGC 646 is a large barred spiral galaxy located in the constellation Hydrus. Its speed relative to the cosmic microwave background is 8,145 ± 19 km/s, which corresponds to a Hubble distance of 120.1 ± 8.4 Mpc. NGC 646 was discovered by British astronomer John Herschel in 1834. It forms an interacting galaxy pair.
NGC 5777 is a large edge-on spiral galaxy located in the constellation Draco. Its speed relative to the cosmic microwave background is 2,210 ± 5 km/s, which corresponds to a Hubble distance of 32.6 ± 2.3 Mpc. NGC 5777 was discovered by German-British astronomer William Herschel in 1789.
NGC 1009 is a large spiral galaxy in the constellation Cetus. Its speed relative to the cosmic microwave background is 5,594 ± 24 km/s, which corresponds to a Hubble distance of 82.5 ± 5.8 Mpc. NGC 1009 was discovered by American astronomer Edward Swift in 1886. The luminosity class of NGC 1009 is II and it has a broad HI line. To date, five non-redshift measurements yield a distance of 91.940 ± 3.045 Mpc, which is just outside the distance values of Hubble.
NGC 747 is a spiral galaxy located in the constellation Cetus. Its speed relative to the cosmic microwave background is 5,100 ± 19 km/s, which corresponds to a Hubble distance of 75.2 ± 5.3 Mpc. NGC 747 was discovered by American astronomer Francis Leavenworth in 1886. The luminosity class of NGC 747 is II and it has a broad HI line. To date, four non-redshift measurements yield a distance of 83.900 ± 4.166 Mpc, which is within the Hubble distance range. Note, however, that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy and that consequently the diameter of NGC 747 could be approximately 23 .9 kpc. In the same area of the sky there are, among other things: the galaxies NGC 713, NGC 731, NGC 755 and NGC 767.
NGC 5008 is a massive barred spiral galaxy located in the Boötes constellation.
NGC 5683 is a type S0-a lenticular galaxy with a bar located in the Boötes constellation. It is 513 million light-years away from the Solar System and has an approximate diameter of 256,000 light-years meaning it is larger compared to the Milky Way. NGC 5683 was discovered by George Johnstone Stoney on April 13, 1850.
NGC 7222 is a large barred spiral galaxy with a ring structure, located in the constellation Aquarius. It is located 570 million light-years away from the Solar System and was discovered by German astronomer, Albert Marth on August 11, 1864.
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 4017 is an intermediate spiral radio galaxy located in the constellation Coma Berenices. Its speed relative to the cosmic microwave background is 3,748 ± 21 km/s, which corresponds to a Hubble distance of 55.3 ± 3.9 Mpc. NGC 4017 was discovered by German-British astronomer William Herschel in 1785.
NGC 5504 is an intermediate barred spiral galaxy located in the constellation Boötes. Its speed relative to the cosmic microwave background is 5,482 ± 17 km/s, which corresponds to a Hubble distance of 80.9 ± 5.7 Mpc. NGC 5504 was discovered by French astronomer Édouard Stephan in 1880.