The Atmospheric Laboratory for Applications and Sciences – 3 (ATLAS-03) was the primary payload aboard STS-66. It continued the series of Spacelab flights to study the energy of the sun and how it affects the Earth's climate and environment. The ATLAS-03 mission made the first detailed measurements from the Shuttle of the Northern Hemisphere's middle atmosphere in late fall. The timing of the flight, when the Antarctic ozone hole is diminishing, allowed scientists to study possible effects of the ozone hole on mid-latitudes, the way Antarctic air recovers, and how the northern atmosphere changes as the winter season approaches.
