Virgo A

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Virgo A

(3C274) An intense radio source in the Virgo cluster that is associated with the galaxy M87. It is 16 megaparsecs distant and has a flux density of 198 jansky at a wavelength of 20 cm. M87 is a giant elliptical galaxy that is unusual in possessing an optical jet extending from its central regions. Jet and nucleus are both sources of nonthermal radio and X-ray radiation due to synchrotron emission from plasma as it is accelerated along the jet. M87 is the nearest active galaxy. Hubble Space Telescope observations of a disk of hot gas in the core of M87 show it to be rotating rapidly, a signature of a supermassive black hole at the center of the galaxy, with a mass more than three billion times greater than that of our Sun.

The thermal X-ray emission in the Virgo cluster is strongly concentrated to the region around M87, and to bind this gas gravitationally the galaxy must have a total mass of more than 1013 solar masses. A direct determination of the mass-to-luminosity ratio in this galaxy requires it to have a massive dark halo. The galaxy is surrounded by over a hundred thousand globular clusters.

Virgo A

[′vər·gō ′ā]
(astronomy)
A radio galaxy; it is associated with the galaxy M 87 (NGC 4486).
References in periodicals archive ?
Messier 87 in Virgo is a good example of a bright elliptical galaxy.
The image was made during the test-phase of LOFAR, and targeted the giant elliptical galaxy Messier 87, at the center of a galaxy cluster in the constellation of Virgo.
The previous record-holding black hole, Messier 87, comes in at a comparably paltry 6.
Munich, May 21 (ANI): Using ESO's (European Southern Observatory's) Very Large Telescope (VLT), astronomers have succeeded in measuring the size of giant galaxy Messier 87 and were surprised to find that its outer parts have been stripped away by still unknown effects.
Numerical models predict that the halo around Messier 87 should be several times larger than our observations have revealed.