AAO image reference AAT 75. « Previous || Next »
Top left is NE. Image width is about 19 arc min
Image and text © 1991-2010, Australian Astronomical Observatory, photograph by David Malin.
Here we see two bright stars whose radiant energy is beating down on to the surface of a dark cloud, very similar to the Horsehead in Orion. The cloud itself is opaque and because of that, very cold inside. These conditions are ideal for the formation of organic molecules on the surfaces of the chilled dust particles. The opacity of the cloud protects the fragile molecules within from the energetic radiation of nearby stars, but as its surface is gradually warmed and eroded, the delicate organic molecules are destroyed and the hydrogen released glows as a distinctive red emission nebula.
Related Images
AAT 74. Reflection nebula in NGC 6188
AAT 74a. Reflection nebula in NGC 6188
AAT 75a. The NGC 6188 nebula and NGC 6193 (wide field)
Constellation of Ara (external site)
For details of photographic exposure, search technical table by AAT reference number.