What looks in this photo like a comet with a stunning, beautiful tail is actually the Space Shuttle Atlantis, moments after it dumped a huge payload of urine and other waste in preparation for landing last week.

Space.com: "The beautiful trail in the sky looked like a mysterious celestial event. In reality, it was urine. Some skygazers were treated to the unexpected view of a bright sparkling glow Wednesday night, created when astronauts aboard the space shuttle Discovery dumped the waste out into space...Waste water usually freezes upon jettison into a cloud of tiny ice droplets. Then when the sun hits, the ice sublimates directly into water vapor and disperses in space. A number of people in North America apparently spotted Wednesday's dump, and some sent pictures to the Web site SpaceWeather.com."