Scientists shocked to discover plankton on exterior of International Space Station

For those who believe there could be life in space, this discovery is huge: Scientists have reportedly found traces of plankton on the outside of the International Space Station.

Russian scientists discovered the plankton while studying samples from the exterior of the ISS — samples they only found because they were doing a routine cleaning of the ISS' windows. Scientists are now baffled about how these marine organisms made their way into space.

Vladimir Solovyev, head of ISS's Russian segment and orbital mission, told RT the plankton traces prove that life in space is possible for some organisms — the plankton survived even in subzero temperatures and without oxygen. "The results of the experiment are absolutely unique," Solovyev told Russia's Itar-Tass. "This should be studied further."

The even stranger part of the story is that the Russian scientists discovered the plankton aren't native to Baikonur, Kazakhstan, from where the Russian modules of the station blasted off. The scientists speculate that air currents may have carried the plankton into space.

NASA has not yet commented on the plankton discovery.