Centaurus A
Right Ascension | 13 : 25.5 (h:m) |
---|---|
Declination | -43 : 01 (deg:m) |
Distance | 15000.0 (kly) |
Visual Brightness | 7.0 (mag) |
Apparent Dimension | 18 x 14 (arc min) |
Discovered by James Dunlop in 1826.
This galaxy is situated in the M83 group of galaxies. It is one of the most interesting and peculiar galaxies in the sky, and is a strong source of radio radiation (therefore the designation Centaurus A); it is actually the nearest radio galaxy. It is of intermediate type between elliptical and disk (spiral) galaxies: The main body has all characteristics of a large elliptical, but a pronounced dust belt is superimposed well over the center, forming a disk plane around this galaxy.
This galaxy seems to have "eaten" at least one larger spiral in the last few billion years. However, the present author is not sure if this alone explains the unique appearance of this galaxy: It may well be that this is one of the rare "links" between "normal" ellipticals and "normal" disks.
In the radio part of the spectrum, Centaurus A exhibits two vast regions of radio emission, starting in prolongation of the polar axis of the disk of NGC 5128 and extending many hundreds of light years to each side.
Our image was obtained by David Malin with the Anglo-Australian Telescope. This image is copyrighted and may be used for private purpose only. For any other kind of use, including internet mirroring and storing on CD-ROM, please contact the Photo Permissions Department (photo at aaoepp.aao.gov.au) of the Australian Astronomical Observatory.
The bright blue-green star in the middle of the left part of the dust belt in this image is supernova 1986G (the only SN discovered in Centaurus A so far) which was discovered on May 3, 1986, by Reverend Robert Evans, and reached mag 12.5 (see IAUC 4208). The blue-green color occurs because David Malin could take the red plate used in this composit image only one year after the supernova occurred, and it had faded away at that time.
NGC 5128 was discovered by James Dunlop on August 4, 1826, and cataloged by him as Dun 482. John Herschel was the next to see it on June 1, 1834 from South Africa, and cataloged it as h 3501, which became GC 3525 in his General Catalogue of 1864, and NGC 5128 in J.L.E. Dreyer's NGC.
In the SAC 110 best NGC object list. In John Caldwell's observing list. In the Astronomical League's Southern Sky Binocular Club list. Caldwell 77 in Patrick Moore's list.
Last Modification: April 24, 2007