It’s a long way to the International Space Station (Image: NASA)

Living in space doesn’t come cheap. A report from NASA’s internal auditor, inspector general Paul Martin, says the space agency has underestimated the cost of keeping the International Space Station running until 2024. In particular, buying flights to the ISS from private companies rather than Russia is expected to increase costs.

Last week, NASA awarded contracts totalling $6.8 billion to Boeing and SpaceX, who will begin launching astronauts to the ISS on board private spacecraft in 2017. The agency currently buys rides on a Russian Soyuz craft for more than $70 million a seat, but is under pressure from US politicians to resume launches from US soil.

NASA expects its annual spend on the ISS to increase from $3 billion to $4 billion over the next 10 years, with the largest increase coming from transportation costs. Martin says these estimates are unrealistic, because NASA is using the Soyuz price as a baseline for private flights and is likely to have to pay Boeing and SpaceX more than it pays Russia.


It may also have to stump up for more un-crewed cargo missions to the station if international partners don’t maintain supply runs. The European Space Agency has already retired its cargo ships, and Japan and Russia have not yet committed to an extension past 2020.

Efforts to attract private research money to the ISS have also been unsuccessful. Martin thinks that private firms like pharmaceutical companies are put off by restrictions that grant the US government patent rights for any research done on the space station, and that NASA must push Congress harder for changes in legislation that would let firms retain their patents.