Around the nucleus of M83 (NGC 5236)
Tags: galaxy, spiral, nebula, dust
Messier 83 is a giant spiral galaxy on the borders of Hydra
in the southern sky. By chance we see it almost face-on and it is close enough (about 20 million light years distant) that some of its brightest stars are resolved. As in all spirals, the brightest stars are the youngest and for most of their short lives such stars are also very hot, so they appear blue on this true-color photograph, They mark the convex edges of the spiral arms of M83 and are not to be confused with the random scattering of relatively nearby Milky Way stars across the picture.
The spiral arms of M83 seem to begin as dust lanes, seen as dark against a faint yellow haze around the bright nucleus. The yellow haze is the 'bulge' of M83, the population of old, faint, yellow stars that is most numerous towards the nucleus. It is from the bright nuclear region that the curved dust lanes seem to emerge. They can be traced out into the spiral arms proper, where they become denser and fragmented, perhaps because of star formation, which turns dark dust into pink nebulae, or clouds of glowing gas.
Made from "Tek 1" CCD RGB data obtained by Steve Lee and David Malin in March 1997
Top left is NE. Image width is about 7 arc min.
© Australian Astronomical Observatory