WASHINGTON — Irked by NASA’s plan to spend $150 million of its $1 billion in economic stimulus money on commercial crew and cargo systems, Sen. Richard Shelby (R-Ala.) is holding up the release of funds Congress approved for the space agency in February as part of the American Recovery and Reinvestment Act.

Shelby‘s press secretary could not be reached for comment at press time June 5, though multiple congressional sources confirmed the senator had intervened to tie up most if not all of NASA’s $1 billion until resolving his concerns about how it will be spent.

During a May 21 Senate Appropriations commerce, justice and science subcommittee hearing, acting NASA Administrator Christopher Scolese acknowledged that only $250 million of the $400 million in stimulus money Congress directed toward exploration would go to development of the Orion Crew Exploration Vehicle and its Ares 1 rocket. He said the remaining $150 million would be used to foster development of commercial vehicles intended to deliver cargo and eventually astronauts to the international space station. Of that $150 million, $70 million would go toward activities that support the space station, including development of specifications and standards for human spaceflight, including docking requirement and human-rating standards. The remaining $80 million would be awarded to firms interested in developing crewed vehicles.

During the hearing, Shelby, the subcommittee’s ranking member, accused NASA of ignoring congressional guidance by failing to use the entire sum to accelerate development of the Constellation program’s Ares and Orion vehicles and get an earlier start on a heavy-lift launcher and lunar lander work led by the Marshall Space Flight Center in

“Congress specifically provided $400 million to the exploration program through the 2009 stimulus bill to close the gap between the shuttle and Constellation programs,” he said. “It’s my understanding that NASA’s spending plan included a redirection of $150 million for new initiatives related to commercial crew and cargo transportation. It appears these funds are for entirely new activities that have not been formally presented or reviewed by Congress.”

Shelby also made clear during the hearing that he does not want NASA using money intended for Constellation to fund private-sector efforts to develop and demonstrate crewed systems. “I believe that manned spaceflight is something that is still in the realm of government, because despite their best efforts, some truly private enterprises have not been able to deliver on plans of launching vehicles,” he said, specifically referring to Space Exploration Technologies, the Hawthorne, Calif.-based company that has been pushing NASA and Congress expand the Commercial Orbital Transportation Services (COTS) program to include crewed demonstration flights.

It is unclear how Shelby‘s concern about the $400 million in space exploration money could impact NASA’s ability to obligate the larger stimulus package. One Senate aide said congressional appropriators “want to give the ranking minority member the option of signing off and being comfortable” with NASA’s spending plans. The aide said meetings were under way at press time to resolve the standoff.