NGC 4442
NGC 4442 also known as UGC 7583, is a barred lenticular galaxy, luminous infrared galaxy and active galaxy in the constellation of Virgo. The galaxy is 48 million light years away at a spectroscopic redshift z = 0.00117. The galaxy has a visual magnitude of 10.6, which is visible using a telescope with an aperture of 6 inches or more, and it can be observed in both hemispheres during certain times of the year. The galaxy is located in the Virgo Cluster, along with other notable galaxies such as Messier 87 and the Eyes Galaxies. The galaxy was discovered on April 15, 1784 by German-British astronomer, William Herschel.
Physical properties
NGC 4442 is medium-sized barred lenticular galaxy located in the Virgo Cluster, and it was listed as the 1,062nd object in the Virgo Cluster Catalog. The galaxy has an estimated width of 83,000 light years across, or about 3/4 the size of the Milky Way. This size is based on an 2MASS K-band total angular diameter of 5.95 arcmin and a mean redshift-independent distance of 48 million light years.NGC 4442 has a stellar mass of 162 billion, or 10^11.21. The galaxy is roughly 3/4th the stellar mass of the Milky Way. The galaxy has a large stellar population of red-giant branch stars, with an average age of 3.92 billion years old, and an mean mass of 1.09. The neutral atomic hydrogen in the galaxy has an mass of 54.9 million, and this gas is usually found in the outer regions of the galaxy such as the galactic halo.
NGC 4442 has a K-band luminosity of 550 billion, or 10^11.74 and therefore it is classified as a luminous infrared galaxy. The galaxy is one of the closest luminous infrared galaxies known, with a similar distance to other nearby luminous infrared galaxies such as Messier 77.
NGC 4442 has a star-formation rate of 10.7 per year, extremely high for gas-poor lenticular galaxies. Despite its high-star formation rate it is not classified as a starburst galaxy, and the galaxy's star-formation rate is comparable to other lenticular galaxies such as Messier 85. The total mass of the ionized atomic hydrogen in the galaxy, which mostly includes the star-forming regions is 109.6 million, or 10^8.04.
The galactic center of NGC 4442 shows a clear active galactic nucleus, which is a region at the center of a galaxy that is extremely luminous and bright. The active galactic nucleus is powered by a massive supermassive black hole with a mass of 5.25 billion or roughly 1,200 times more massive than Sagittarius A*, which is the central black hole of the Milky Way.
NGC 4442 has a population of 219 globular clusters, however some of them are potentially not globular clusters and are candidates. The globular clusters have angular radii between 0.0103 and 0.1042 arcsecs, corresponding to a half-light radius ranging from 2.41 to 24.3 light years.