Suppose a spacecraft is conducting research on Mars, or any other planet. There is a chance (albeit small) that some microscopic organism living on that strange planet will make the crossing with the spacecraft returning to Earth. We do not know whether an alien organism, bacteria or virus is healthy for humanity.
Answer
This question is very important for the future International Mars Sample Return mission to Mars. The European space agency ESA (and therefore also Belgium), NASA and the Japanese counterpart are working together on this mission.
Dust, rocks, ice and atmospheric gas would return to Earth in a special laboratory that is more complex than the laboratories where the most dangerous viruses are studied. Scientists only get their hands on the Mars samples after a thorough bacteriological and toxic examination.
The space agencies are therefore aware of the danger of bringing unknown Martian life to Earth. Conversely, they are also very aware of the danger of contaminating Mars with Earthly life!
Answered by
Dr Christian Muller
Earth and space sciences
Ringlaan 3 1180 Brussels
http://www.aeronomy.be/
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