NASA's Launch Blog - THEMIS Mission
DELTA LAUNCH CONTROL ON DECK!
"4:35 p.m. - THEMIS stands for Time History of Events and Macroscale Interactions during Substorms. It's a long name, but a fascinating mission: The set of five probes will investigate what causes the auroras in the atmosphere to change from slowly shimmering waves of light to wildly shifting streaks of color. With this information, scientists may better understand why and how certain components of space storms disturb satellites, power grids and communications systems here on Earth. "
"Launch is targeted for the opening of tonight's window,
which extends from 6:05 p.m. until 6:23 p.m."