Reports from the International Space Station are that plankton, the tiny creatures typically found living in the earth's oceans, subject to wherever the currents go, have been living on the outside of the hull.

Russian cosmonauts said they discovered traces of plankton that were alive, despite being exposed to the harsh, airless and solar radiation-filled vacuum of space.

That would be more of a remarkable find if the Russians' American shipmates didn't challenge the assertion microscopic sea life is anchored to the orbiting laboratory, explains a report by Forbes.

Actually, the explorers on the space station reportedly haven't said anything about the difference of opinion over the discovery; instead, the differing versions of what's going on overhead are being debated through the media, with competing quotes from space agency representatives here on Earth.

"Results of the experiment are absolutely unique. We have found traces of sea plankton and microscopic particles on the illuminator surface. This should be studied further," Vladimir Solovyev, chief of the Russian ISS orbital mission, told Russia's state-owned ITAR-TASS news agency.

The Russian report suggests the plankton and other previous discoveries have shown such organisms can survive and even grow outside the space station.

"Results of the scope of scientific experiments which had been conducted for a quite long time were summed up in the previous year, confirming that some organisms can live on the surface of the International Space Station (ISS) for years amid factors of a space flight, such as zero gravity, temperature conditions and hard cosmic radiation. Several surveys proved that these organisms can even develop," the Russians announced.

Meanwhile, the National Aeronautics and Space Administration has told reporters any talk of ocean organisms flourishing where other Earth life can't is up in the air.

"As far as we're concerned, we haven't heard any official reports from our Roscosmos (Russia's space agency) colleagues that they've found sea plankton," NASA spokesman Dan Huot was quoted in a story by Space.com. "What they're actually looking for is residues that can build up on the visually sensitive elements, like windows, as well as just the hull of the ship itself that will build up whenever they do thruster firings for things like re-boosts. That's what they were taking samples for. I don't know where all the sea plankton talk is coming from."

NASA scientists have said it's possible plankton could be a contaminant that hitched a ride from Earth when the space station modules were lifted into orbit.

The surface of the International Space Station, which has spent nearly 6,000 days in Earth orbit since its assembly began in 1998, is heavily polluted, largely from the engine residue created by delivery spacecrafts.