"Rubber-based rocket fuel burned with nitrous oxide is the preferred propellant of the burgeoning space-tourism industry, and chemists suspect such hybrid engines emit sooty black carbon. Closer to Earth, the stuff has been shown to soak up extra radiation from the sun and contribute to climate change. 'This study was a natural extension of the climate-research community gaining a greater and greater appreciation of black carbon in terms of global radiative forcing,' said Martin Ross, an atmospheric scientist at The Aerospace Corporation in El Segundo, California, and leader of the research funded in part by his employer."