NGC 4526 is a lenticular galaxy in the Virgo constellation that is seen nearly edge-on. It belongs to the Virgo cluster and is one of the brightest known lenticular galaxies.
What is NGC 4526?
The inner nucleus of this galaxy displays a rise in stellar orbital motion that indicates the presence of a central dark mass. The best fit model for the motion of molecular gas in the core region suggests there is a supermassive black hole with about 450 million times the mass of the Sun. This is the first object to have its black-hole mass estimated by measuring the rotation of gas molecules around its centre with an Astronomical interferometer (in this case the Combined Array for Research in Millimeter-wave Astronomy).
Supermassive black hole
A supermassive black hole (SMBH) is the largest type of black hole, on the order of hundreds of thousands to billions of solar masses (M☉), and is found in the centre of almost all currently known massive galaxies. upermassive black holes have properties that distinguish them from lower-mass classifications. First, the average density of a SMBH (defined as the mass of the black hole divided by the volume within its Schwarzschild radius) can be less than the density of water in the case of some SMBHs. This is because the Schwarzschild radius is directly proportional to mass, while density is inversely proportional to the volume. Since the volume of a spherical object (such as the event horizon of a non-rotating black hole) is directly proportional to the cube of the radius, the minimum density of a black hole is inversely proportional to the square of the mass, and thus higher mass black holes have lower average density.
In addition, the tidal forces in the vicinity of the event horizon are significantly weaker for massive black holes. As with density, the tidal force on a body at the event horizon is inversely proportional to the square of the mass: a person on the surface of the Earth and one at the event horizon of a 10 million M☉ black hole experience about the same tidal force between their head and feet. Unlike with stellar mass black holes, one would not experience significant tidal force until very deep into the black hole.
Image: NASA / ESA
Text: Wikipedia contributors. “NGC 4526.” Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 29 Jul. 2017. Web. 10 Aug. 2017. & Wikipedia contributors. “Supermassive black hole.” Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 31 Jul. 2017. Web. 10 Aug. 2017.