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This four colour infrared composite image of the Lambda Orionis ring (Sh 2-264) was created from the IRIS version of the IRAS infrared data. This image is just a detail of the full IRAS all-sky image which is viewable through the Milky Way Explorer.
The ring can perhaps best be explained by a supernova very close to the O8 III multiple giant Lambda Orionis about 1 million years ago. Sh 2-264 is ionised by Lambda Orionis, and to a lesser extent, the 11 B-class stars near to it, and is part of the Gould Belt. The M2 Iab supergiant Betelgeuse is visible as the bright white star just to the upper left of the ring.