The International Space Station, long a symbol of international cooperation in space even among former adversaries, could become the next pressure point as the US tries to raise the stakes for Moscow after Russia's takeover and annexation of Crimea.
On Wednesday, Michael O'Brien, NASA's associate administrator for international and interagency relations issued a memo to the agency's staff suspending bilateral contacts with Russia unless a specific activity has been given an exemption.
"This suspension includes NASA travel to Russia and visits by Russian Government representatives to NASA facilities, bilateral meetings, email, and teleconferences or videoconferences." wrote Mr. O'Brien. A copy of the memo was posted on the website SpaceRef.com.
Bilateral contacts related to the operation of the space station are exempt, as are meetings held outside of Russia that involved additional countries – such as those that might be include the participation of the station's other main partners, Canada, Europe, and Japan.
NASA's move is something of a diplomatic Post-it note; the two countries' space programs aren't engaged in many bilateral activities. Indeed, should operation of the space station come directly into play, the US and the other partners have the most to lose.
They have the heaviest investment in the $150 billion orbiting outpost, and they cannot get into space without Russia, which has served as America's taxi service for delivering and retrieving US crew members from the space station, as well as delivering cargo to the station.
So far, the Ukraine crisis has not interrupted US-Russia cooperation on the space station. But with the issuance of NASA's memo Wednesday, the question everyone is waiting to see answered is how Russian President Vladimir Putin responds.
"Is he going to be a rational international leader, or is he going to going to go the way of the egomaniac autocrat?" asks Joan Johnson-Freese, a professor at the US Naval War College in Newport, R.I., and a specialist on space-security and space-policy issues.
The motive behind including the Russians in the space station in first place stemmed partly from the country's experience with its own space station, Mir. But it also stemmed from a desire after the fall of the Soviet Union to keep Russian rocket scientists from finding work in countries whose intentions toward the US were anything but honorable.
NASA's move comes as no surprise, says Dr. Johnson-Freese.
Congress has banned NASA from working with China because of concerns about technology transfers and human rights. If NASA were to continue to work with Russia, that would say, "It's OK to take over someone else's sovereign territory," she says.
"If the United States wants to avoid looking extremely hypocritical, this was going to be coming," she says.
One US astronaut and two cosmonauts arrived at the station March 27 after a two-day trip aboard a Russian Soyuz capsule. On April 9, Russia is slated to launch a Progress resupply craft to the station.
Even so, Wednesday's memo is expected to intensify the debate in Congress over restoring NASA's ability to launch astronauts from US soil. With the end of the US space shuttle program in 2010, Russia became the only country in the partnership able to transport crew members.
"We've always known that dependence carries risks," Johnson-Freese says. But the risk "has been exponentially magnified" by recent events.
NASA has contracted with commercial providers such as Space Exploration Technologies, Sierra Nevada Corporation, and Boeing to develop launch systems that can carry humans. The agency will eventually select one for actual transportation contracts.
But some lawmakers have been lukewarm about the commercial approach, and the agency has been directed to continue developing a multipurpose launch system for low-Earth orbit and deep-space exploration.
The first flight for "commercial crew" initially was envisioned for 2015, but funding hasn't kept pace. Now the first flights aren't anticipated until 2017. Meanwhile, each seat on a Soyuz runs about $71 million, up from $51 million when the US first began buying seats after the shuttle program ended, according to an analysis by the National Space Society, which supports commercial development of space.
The Obama administration's fiscal 2015 budget request seeks $848 million to keep the commercial-crew program on track for 2017. And advocates would like to see Congress restore $171 million withheld from the program during the current fiscal year.