[2] Succeeding Charles Bolden, Lightfoot became the space agency's acting Associate Administrator on March 5, 2012.

Lightfoot moved to NASA's John C. Stennis Space Center in 1999 as chief of propulsion test operations.

[9] In February 2012, NASA announced that Lightfoot would become the space agency's acting Associate Administrator as of March 5, 2012.

The position opened when Chris Scolese was named the new director of the Goddard Space Flight Center in Greenbelt, Maryland.

[15][16] A native of Montevallo, Alabama, Lightfoot has received several awards during his career, including the Presidential Rank Award for Meritorious Executives in 2006 and a NASA Outstanding Leadership Medal in 2007 for "outstanding and exemplary leadership of the Shuttle Propulsion Office" and "assuring safety for the shuttle's return to flight".