spiral galaxy
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae'' million
light year
A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...
s away in the
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The origins of the e ...
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 were found, and the measurement of their periodicity gave a net distance estimate of (). This is consistent with the distance estimate determined through
redshift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in f ...
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 mass
The solar mass () is a standard unit of mass in astronomy, equal to approximately . It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. It is approximately equal to the mass ...
es. Based upon the yellowish color, it may have been a member of a binary star system.