The International Space Station (ISS). | Copyright: NASA
Cologne (Germany) - Less than a month ago, Russian news agency ITAR-TASS made international headlines, reporting on the discovery of living and thriving sea plankton on the outside-surface of the International Space Station (ISS) by Russian cosmonauts. The news caused a heavy controversy and mystery. In the absence of a scientific paper and because it had no further information itself, even NASA challenged the report about the discovery. Now, the German frontier-science news magazine GreWi.de has the first official statement made by the German Aerospace Center (DLR) that supports the original report at least in parts.
Just days after the original report was published NASA-spokesman Dan Huot told Space.com: "As far as we're concerned, we haven't heard any official reports from our Roscosmos colleagues that they've found sea plankton. (...) I'm not sure where all the sea-plankton talk is coming from. The Russians did take samples from one of the windows on the Russian segment, and 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."
Following the original reports GreWi unsuccessfully tried to get official statements from different sources such as ESA, it was GreWi-reader Tanja Wulff who contacted the German Aerospace Center (DLR) via Facebook - and finally got the following reply by DLR-spokeswoman Alisa Wilken:
"At an extravehicular activity Russian cosmonauts took samples from the outside of the Russian module. Those samples were then analyzed in a laboratory on Earth. Within this sample bacterial DNA was discovered.
However, the method by which the samples were analyzed in this case is disputed, as it can not detect all kinds of bacteria and it also can not test whether the discovered bacteria are living and thriving or not.
Also the biomass that can be extracted from such samples is strongly limited so that at the moment no further tests could have been conducted on it. To do this, more samples would bee needed."
So there was and almost likely still are microorganisms on the outside of the ISS.
The question however is: what exactly are they, are they living and thriving, how did they got there and where do they come from?