If you go outside and look east not long after sunset in the winter, you'll see Orion rising. In his familiar outline, his left shoulder is marked by the red supergiant Betelgeuse, and his other shoulder by the blue giant Bellatrix. Just above these two stars, where Orion's head would be, looks empty. But deep exposures reveal a sprawling cloud of hydrogen there, a vast nebular star factory.

The cloud is choked with dust as well, which is opaque and dark in visible light. But when NASA's WISE observatory turns its infared-sensitive eye to this object, it sees the picture above: a huge ring of softly glowing dust. The star in the center is Lambda Orionis, a red supergiant like Betelgeuse (which itself is the bright star in the lower left, looking blue in this false color image), dimmed considerably by the thick dust. Lambda Ori, along with several other stars, warms the dust, making it glow in the infrared. Long fingers point to the center of the structure; these are dense towers of gas and dust being eroded by the radiation of the stars in the center, like sandbars in a river. Eventually they will completely dissolve away.

Sometime before then, though, Lambda Ori will most likely explode, which will expand outward into this bubble. It may not have enough power to destroy this huge structure, but it will probably be joined by other stars over time, and the cloud will disperse, revealing all the other stars there. Once that happens, Orion's head will glow brilliantly from the combined light of all the stars born there... and he may no longer look much like a hunter. I wonder if future generations will rename him?

Image credit: NASA/JPL-Caltech/UCLA

Original Image

Original Post