Image: NASA/JPL-Caltech
This one is pretty cool: a wave in space called a "bow shock".
This wispy yellow arc was created by the massive star Zeta Ophiuchi (centre), which emits about 65,000 times more light than the sun. The star is speeding through space at more than 85,000 kilometres per hour - possibly because of the gravitational recoil it experienced when a former companion star exploded in a supernova.
Zeta Ophiuchi sloughs off a strong wind of charged particles that compresses the gas and dust in front of it, creating a curved feature called a 'bow shock' that resembles the shape that water takes in front of a speeding boat (or in this case, a bird's profile).
From the NewScientist: Link