AAO image reference UKS 9. « Previous || Next »
Top left is NE. Image width is about 2 degrees
Image and text © 1983-2010, Australian Astronomical Observatory
Photograph from UK Schmidt plates by David Malin.
The Rosette Nebula exhibits a striking circular symmetry which gives it the appearance of a partly opened rose, an allusion further enhanced by the rich red hues seen in this colour photograph. The colours here are real, but the eye is insensitive to the colour of faint light, so they remain unseen by the human eye, even with the largest telescopes.
Near the centre of the nebula is a cluster of blue stars catalogued as NGC 2244. These stars are responsible for making the nebula visible and for creating the hollowed-out central cavity. This cluster of stars formed in darkness from the gas and traces of dust which now surrounds it, less than a million years ago. NGC 2244 is thus very young on the cosmic timescale, but its existence, along with many others in the Milky Way, is vivid evidence that our Galaxy is actively producing stars.
The gas and dust at the centre of the nebula have been forced away from the bright stars by radiation pressure and the intense stellar wind which is often associated with very hot stars, forming a hollow centred on the cluster. This will gradually expand and dissipate until the stars are free from nebulosity. Perhaps eventually there will be a young open cluster in Monoceros looking like the young open cluster NGC 3293.
Related images
AAT 35. The Rosette Nebula and NGC 2244 cluster (off centre view)
AAT 35a. The Rosette Nebula and NGC 2244 cluster (AAT full field)
Constellation of Monoceros (external site)
For details of object position and photographic exposure, search technical table by UKS reference number.