Right Ascension | 12 : 35.7 (h:m) |
M 89Elliptical Galaxy M89 (NGC 4552), type E0, in Virgo |
---|---|---|
Declination | +12 : 33 (deg:m) |
|
Distance | 60000 (kly) |
|
Visual Brightness | 9.8 (mag) |
|
Apparent Dimension | 4.0 (arc min) |
Discovered 1781 by Charles Messier.
M89 is another member of the Virgo cluster of galaxies, and one of Charles Messier's own discoveries. He cataloged it on March 18, 1781, together with seven other newly discovered galaxies in the Coma-Virgo region (i.e., Virgo Cluster members), and globular cluster M92, to make this his most successful discovery day.
M89 is of elliptical type and nearly exactly circular, and it appears to be smoothly textured. If it is actually of globular shape, or an oblate or prolate spheroid with the rotation axis directed to us, cannot currently be decided, as Kenneth Glyn Jones points out.
David Malin has investigated M89 by deep (long exposure, sensitive) photography with the UK Schmidt telescope (see Nature 227, 279-80, 1979, and DFM's books `Colours of Stars', Cambridge UP 1984, and `A View of the Universe', Cambridge UP 1993; see also the book `Catalogue of the Universe' by P.G. Murdin, D.A. Allen and DFM, Cambridge UP 1979). While this galaxy looks like the prototype of a normal E0 galaxy, and was just known as an only weak radio source, Malin's high sensitivity photographs revealed a faint enveloping structure, which is best visible to the northwestern and southern direction of the galaxy. Therefore, M89 was the first enveloped galaxy discovered, the envelope being extended to more than 150,000 light years from the galaxy. Moreover, a jetlike structure seems to extend to over 100,000 light years distance; this may be a smaller galaxy which is in process of being disrupted by the tidal gravitational force of M89 during an encounter.