On Earth, the United States may be trading bitter accusations with Russia over Ukraine. But in space, it's a different story. The space collaboration between the two nations has survived other diplomatic kerfuffles. And there's no need to worry, NASA says. "We do not expect the current Russia-Ukraine situation to have any impact on our civil space cooperation with Russia, including our partnership on the International Space Station program," said Allard Beutel, a NASA spokesman. "It is in the best interest of all ISS partners not to allow disruption of operations that have maintained continuous human presence on orbit for over a decade."
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Former astronaut says both countries necessary for ISS
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NASA retired its space shuttle fleet in 2011
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Its astronauts have no way to get to and from the international space  station
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Russian Soyuz capsules ferry  U.S. astronauts
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U.S.
@placeholder and Russians train on each other's systems, but one country can't run the station alone, he said.
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U.S.
As for transporting astronauts, NASA said in November that it is seeking to partner with @placeholder companies for human trips to the station as well, by 2017.
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But for now, experts say the @placeholder-Russia relationship on space remains a marriage of convenience.