WASHINGTON — U.S. astronaut Michael Lopez-Alegria has left NASA to become president of the Washington-based Commercial Spaceflight Federation (CSF), an advocacy group for private space companies.

NASA announced Lopez-Alegria’s retirement in a March 12 press release. The former international space station commander will take the reins at CSF on March 19, the group said in a press release.

Lopez-Alegria, a retired U.S. Navy captain, visited space four times during his 20 years with NASA. He most recently served in the Flight Crew Operations Directorate at NASA’s Johnson Space Center in Houston as assistant director for the international space station.

As president, Lopez-Alegria will oversee CSF’s staff and serve as the chief Washington liaison for the group’s member companies. He succeeds Craig Steidle, the retired U.S Navy admiral and former senior NASA official who resigned from CSF in September for medical reasons.

“We are incredibly excited to have someone as capable as Michael Lopez-Alegria leading the Commercial Spaceflight Federation,” CSF Chairman Eric Anderson said in a statement. “Michael is a leader and a true pioneer whose first-hand experience with spaceflight and the International Space Station will be invaluable to our members and to the Federation.”

Lopez-Alegria flew on three space shuttle missions between 1995 and 2002. His fourth space mission began in September 2006 when he flew on a Russian Soyuz capsule to the international space station. His seven-month mission set a new American record for longest spaceflight.

Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.