 Our solar system is filled with places and phenomenon capable of inspiring our greatest imagination and curiosity. And then there's Uranus, seemingly only capable of inspiring our greatest inner child. Always the butt end of an astronomical joke, the pungent punchline to a never-ending streak of stifled giggles. But despite its bum rap, Uranus was in the news recently because astronomers have finally discovered what the clouds in its upper atmosphere are made of. Scientists took silent but deadly aim at the planet using the Gemini Observatory, one of the most powerful probes in the world. After many hours of staring intently at Uranus, they were able to measure the presence of hydrogen sulfide in the atmosphere, a gas that smells a lot like rotten eggs. Now there's a couple of reasons why this is interesting. First off, studying the upper layers of Uranus allows us to understand what's going on deeper in the atmosphere where the sun don't shine. And number two, it allows us to compare Uranus to other gas giants in the solar system. Both Jupiter and Saturn, for example, have clouds mostly made of ammonia, not hydrogen sulfide. Now this kind of chemical difference means that the planet's likely formed in different conditions. And that difference was imprinted on the final makeup of the planet. So now you can tell your friends that the gas around Uranus smells bad, because astronomers said so. And both friends and enemas alike can probably agree that while Uranus' name makes us laugh, what we can learn from the solar system from it is worth every joke.