On Jul/31/2020 at 13:03, David Spain wrote :
On 2020-07-30 8:36 PM, JF Mezei wrote:
[snip]
The other worry, especially in a COVID context is how to ensure humans
who goto mars never return anything that could potentially wipe out
human ciovilization?

Just because the ground where a robotic lander has found only dead life
doesn't mean that there isn't something alive elsewhere, especially if
any digging happens at the colony to get water and whatever is needed to
make methane and O2.


That's why I'm not a big fan of sample return directly to Earth instead
of the ISS or its replacement, commercial or otherwise. But I'm the
cautious type. Some folks are willing to die on Mars, either for the
right or wrong reasons....

Personally, I think the risk of bio-contamination is very small, even if
there is life on Mars. If you bring back a sample containing living
organism from Mars, and accidentally spill its contents in the wild, I
would think that the probability that such a spill would do harm on
Earth is about the same as the risk of an asteroid wiping out humanity.
You don't find viruses that can contaminate plants and animals, it is
much more unlikely to find something that thrive on Mars and in Earth
inhabitants. That said, I do think that we should allocate more
resources to searching celestial objects that could impact Earth and to
strategies to react to the threat if we do find a major impactor coming
towards Earth. We should also handle with care any sample brought back
from Mars. Even if the risk is very low, the consequences could be very
high.


Alain Fournier