Hi, quick question for you guys. I was having a discussion the other day with a friend of mine, about whether it was possible to ignite the atmosphere of a planet, specifically gas giants; considering many are made of flammable gasses and compounds (hydrogen, methane etc...). I would have thought that without oxygen, one wouldn't be able to spark a flame anyway, but i would just like to know if there was any other way, and what would happen to the make up of the planet if it did. I'm not an astronomer or anything like that, so was just hoping if you guys could enlighten me. Cheers!