AAO image reference AAT 86. « Previous || Next »
Top left is NE. Image width is about 4.6 arc min
Image and text © 1992-2010, Australian Astronomical Observatory, photograph by David Malin.
NGC 6822 is a nearby irregular galaxy in Sagittarius, reminiscent of the Large Magellanic Cloud (LMC). Like the LMC it contains many, extremely hot stars of the Wolf-Rayet type, stars which often have intense stellar winds blasting from their surfaces. Small groups of such stars are found at the centres of the bubble nebulae seen here, which are are the result of the stellar winds colliding with the more or less stationary interstellar medium in NGC 6822. At the interface of the collision, the interstellar medium glows, producing a thin, luminous bubble. Such bubbles are rare in the more turbulent Milky Way galaxy, but Henize 70 in the Large Magellanic Cloud is similar.
Related Images
AAT 26. A galaxy of the Local Group, NGC 6822
Constellation of Sagittarius (external site)
For details of photographic exposure, search technical table by AAT reference number.