At the risk of looking like a fool come December, I think we've got an early favorite for 2013's most adorable nebula. As this National Radio Astronomy Observatory video explains, this nebula looks just like a manatee.
While astronomers Miller Goss and Amy Mioduszewski spend much of the video above focused on the actual science behind the nebula's formation and its appearance, you can see an image of the nebula itself on the left — you can click on the image for a closer look. Previously known simply as W50, the nebula is located about 18,000 light-years away in the constellation Aquila. The nebula is the aftermath of a supernova explosion. Here's how the NRAO explains the nebula's distinctive shape:
The remaining, gravitationally-crushed relic of that giant star, most likely a black hole, feeds on gas from a very close, companion star. The cannibalized gas collects in a disk around the black hole. The disk and black hole's network of powerful magnetic field lines acts like an enormous railroad system to snag charged particles out of the disk and channel them outward in powerful jets traveling at nearly the speed of light. This system of a black hole and its feeder star shines brightly in both radio waves and X-rays and is known collectively as the SS433 microquasar.
Over time, the micro quasar's jets have forced their way through the expanding gases of the W50 bubble, eventually punching bulges outward on either side. The jets also wobble, like an unstable spinning top, and blaze vivid corkscrew patterns across the inflating bulges.
For more, check out the NRAO website, including the all-important comparison shot between the nebula and its marine mammal namesake on the left.
Video by NRAO/AUI/NSF, K. Golap, M. Goss; NASA's Wide Field Survey Explorer (WISE). Image by NRAO/AUI/NSF, K. Golap, M. Goss; NASA's Wide Field Survey Explorer (WISE).