Antarctic mesospheric clouds formed from space shuttle exhaust

New satellite observations reveal lower thermospheric transport of a space shuttle exhaust plume into the southern hemisphere two days after a January, 2003 launch. A day later, ground-based lidar observations in Antarctica identify iron ablated from the shuttle\textquoterights main engines. Additional satellite observations of polar mesospheric clouds (PMCs) show a burst that constitutes 10\textendash20\% of the PMC mass between 65\textendash79\textdegreeS during the 2002\textendash2003 season, comparable to previous results for an Arctic shuttle plume. This shows that shuttle exhaust can be an important global source of both PMC formation and variability.