WASHINGTON – NASA made big news last week when it chose Boeing and SpaceX to build the capsules that will carry American astronauts to the International Space Station beginning in 2017. Making a smaller splash the same week was a report by the NASA Inspector General on the challenges of keeping the station aloft for a new generation of astronauts to visit.
NASA and the White House want to keep the space station in orbit until at least 2024, and the IG's report last week said the agency has found "no major obstacles" to that goal. But the report did note "several areas of risk" that could make the job harder. Here are three of them:
1. Insufficient power to keep running. NASA relies on solar arrays to power the station and motors to keep those arrays pointed at the sun. Perhaps because of a surprising amount of space debris, those arrays and motors are degrading "faster than expected."
2.A limited capacity to get big new parts – such as solar arrays – to the station. NASA has solved its small cargo and re-supply problems with new commercial carriers. It has not replaced the space shuttle as a way to haul big things into orbit
3. A station operating budget NASA says will grow from $3 billion a year to $4 billion by fiscal year 2020. Based on past spending, the IG says that is "overly optimistic" and not enough money.
These examples don't include what the Inspector General calls "the inherent risks" of space travel. For example, NASA puts the odds at 1-in-42 of the station being hit in any six-month period by space debris big enough to penetrate and cause loss of pressure. Extending the station's life cuts those odds to 1-in-4.
Finally, NASA says a primary research area for the station is the effect of long-term space travel on humans. Going to 2024 won't provide enough data to resolve all those questions, either, the IG says, so NASA needs to prioritize.