WASHINGTON — NASA is undertaking a broad reorganization of its Exploration Systems Mission Directorate (ESMD), which was created in 2004 to oversee development of the hardware the U.S. space agency will need to send humans to the Moon by 2020.

The reorganization, affecting some 125 employees, entails shifting management of various exploration programs from NASA headquarters here to regional field centers throughout the country. The ESMD will shrink from six divisions to two, with many of the directorate’s headquarters employees either given other jobs here or transferred to field centers along with their programs.

“The programs are migrating to the centers,” NASA spokesman Michael Braukus said Sept. 7 . “The centers are going to have a much larger role.”

ESMD employees learned of the changes in a meeting at NASA headquarters the morning of Sept. 7. NASA did not announce a new exploration systems chief during the meeting. Doug Cooke has held that job in an acting capacity since June.

Braukus would not say what programs will go to which centers, explaining that those decisions are part of NASA’s overall exploration plan, which was completed this summer but still awaits White House approval. Industry and government sources, however, said NASA intends to give the Johnson Space Center in Houston the Crew Exploration Vehicle program and put the Marshall Space Flight Center in Huntsville, Ala., in charge of developing the new rockets NASA needs to launch the Crew Exploration Vehicle and heavy, Moon-bound cargo payloads.

Braukus identified the new ESMD divisions as Constellation Systems and Advanced Capabilities .

The Constellation Systems Division, led for now by U.S. Navy Capt. Mike Hecker, will oversee development of the Crew Exploration Vehicle, exploration-related launchers, and procurement of commercial services to deliver crew and cargo to the international space station.

The Advanced Capabilities Division, Braukus said, will be led by astronaut Carl Walz and will oversee the lunar robotic exploration program, space station research, the Prometheus nuclear power and propulsion program, and other technology development efforts.

When NASA created ESMD in 2004, the directorate’s first chief, Craig Steidle, set it up to be staffed largely in the Washington area, with hundreds or even thousands of civil servants and contractors eventually working under one roof somewhere in the region. NASA’s new plan shifts most of those jobs out to the field centers.

Braukus confirmed that fewer people will be working for ESMD in Washington but gave no numbers. He said employees affected will be given the opportunity to take new jobs at headquarters or move to one of the field centers.

He said the new organization is expected to be “operational” in October.

Brian Berger is editor in chief of SpaceNews.com and the SpaceNews magazine. He joined SpaceNews.com in 1998, spending his first decade with the publication covering NASA. His reporting on the 2003 Space Shuttle Columbia accident was...