Right ascension 12 40 55.195 Distance 106.8 Mly (32.71 Mpc) Apparent size (V) 3′.4 × 2′.5 Constellation Centaurus | Declination –40° 58′ 35.05″ Type SA(s)c Magnitude 12.3 Apparent magnitude (V) 12.3 | |
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Helio radial velocity +7003256100000000000♠2561 km/s Similar NGC 4605, NGC 4622, NGC 4700 | ||
NGC 4603 is a spiral galaxy located about 107 million light years away in the constellation Centaurus. It is a member of the Centaurus Cluster of galaxies, belonging to the section designated "Cen30". The morphological classification is SA(s)c, which indicates it is a pure spiral galaxy with relatively loosely wound arms.
During 1999, this galaxy was the subject of an extended study using the Hubble Space Telescope to locate Cepheid variable stars. A total of 7001430000000000000♠43±7 were found, and the measurement of their periodicity gave a net distance estimate of 7024102838140236953♠108.7+5.5
−4.9 Mly (7024102753063462857♠33.3+1.7
−1.5 Mpc). This is consistent with the distance estimate determined through redshift measurements. As of the time of this study, NGC 4603 was the most distant galaxy for which a distance estimate had been made using Cepheid variable.
On May 21, 2008, supernova SN 2008cn was discovered at a position 23.″2 north and 4.″7 east of the galaxy center. It was determined to be a high-luminosity Type II-P supernova, with a progenitor tentatively identified as a red supergiant with 15 ± 2 solar masses. Based upon the yellowish color, it may have been a member of a binary star system.