Veteran shuttle astronaut Frederick Gregory will take over as NASA's acting administrator next week. Gregory is currently second in command at the space agency.

He will step into the top job until President Bush nominates, and the U.S. Senate confirms, a replacement for Sean O'Keefe, agency spokesman Robert "Doc" Mirelson said Wednesday.

O'Keefe's last official day is Friday. Citing personal and financial reasons, O'Keefe decided in December to take a job as chancellor of Louisiana State University's Baton Rouge campus after three years as NASA's chief.

Gregory, 64, is a native of Washington, a graduate of the U.S. Air Force Academy and a former Air Force colonel. He flew helicopter combat rescue missions in Vietnam.

He was selected as an astronaut in 1978, and eventually flew on three shuttle missions. He was the first black astronaut to command a shuttle mission.

Gregory served as NASA associate administrator for the Office of Safety and Mission Assurance and then the Office of Space Flight.

In 2002, Gregory was sworn in as deputy administrator.

Published under license from FLORIDA TODAY. Copyright © 2005 FLORIDA TODAY. No portion of this material may be reproduced in any way without the written consent of FLORIDA TODAY.