NGC 4713
NGC 4713 is a spiral galaxy in the constellation Virgo. The galaxy lies about 45 million light years away from Earth, which means, given its apparent dimensions, that NGC 4713 is approximately 40,000 light years across. It was discovered by William Herschel on April 17, 1786.
Characteristics
The galaxy has a small bright nucleus in a short bar, about 0.35 arcminutes long. A pseudoring with a diameter of 0.4 arcminutes is visible. Two filamentary spiral arms emerge from the bar with many knots and fragments. The spiral arm pattern is smooth and symmetrical. The galaxy is a strong source of H-alpha.In images by Hubble Space Telescope NGC 4713 contains a slightly resolved nuclear star cluster with an equivalent-axis half-light radius equal to 0.″07. The mass of the cluster is estimated to be 106.43 ± 0.31 . The nucleus also hosts a black hole with an estimated mass of 104.56 ± 1.66 based on the Sérsic profile of the star cluster. Based on other models, the mass of the central back hole is estimated to be 600 to 9,000 solar masses, which positions it as an intermediate mass black hole. Its nucleus has a spectrum that categorises it as a type 2 transition object, lying between an HII region and a LINER. The galaxy also emits X-Rays and the Fe-K line is faintly detected. The data from Chandra X-ray Observatory show a point X-ray source with a luminosity erg/s. It is a source of soft X-rays.
The galaxy has a large hydrogen disk, as visible in hydrogen line. The disk appears wrapped beyond the optical disk. The central region of the galaxy, were the bar is located, is deficient in hydrogen. The kinematics suggest that the faint outer disk of the galaxy rotates at an angle with respect to the rest of the galaxy.