Q&A with Marc Rayman, chief engineer on NASA’s Dawn mission (members only)

This video released by United Launch Alliance shows the Delta 4-Heavy rocket’s predawn liftoff Aug. 12 from the perspective of a downward-facing camera, capturing dazzling views of the fiery takeoff and the dramatic separation of the launcher’s two hydrogen-fueled boosters.

The satellite awaiting launch early Saturday from California aboard the final flight of the venerable Delta 2 rocket should allow scientists to more precisely track changes in our planet’s ice sheets, using six green laser beams to chart the height and slope of polar ice and glaciers, providing a key input into climate change research.

Ground crews took steps this week to prepare for the next Falcon 9 launch, set for no earlier than Jan. 30 with a telecom satellite for SES and the Luxembourg government, as SpaceX officials stressed their rocket was not to blame for the rumored loss of a mysterious U.S. government payload after liftoff Sunday.