The days of blasting off into the temporary weightlessness of suborbital space are fast approaching—for people with the right stuff in their bank accounts, anyway. Some scientists fear, though, that once the space tourism business becomes established, a steady train of people hurtling into euphoria at the borderline of space could have climactic consequences down here on the surface.
They're talking about soot. Soot or black carbon, which comes from fuel that does not burn completely, ought to
