Who cares if it can support terriasteral life or not?
it's Martian life we worry about!
Liquid Martian brines may be more common than once thought, but they are unlikely to play host to anything that looks like life as we know it, a paper in Nature Astronomy has found. Stable liquid water is considered as one of the necessary ingredients for life to emerge, but under current Mars conditions, it is both too cold …
That is exactly the problem. If you found a microbe on Mars you then have to determine if its indigenous or did it come along on your space craft (or some one else's space craft). Knowing that these places cannot support Earth microbes means that any that you find are more likely to be Martians.
> Who cares if it can support terrestrial life or not?
I think the point here was about the chances of biological contamination from Earth, something which is important if we ever plan to send humans up there. Sterilizing a machine is expensive but doable, but there is no way to sterilize a human (short of boiling it for an hour...).
"short of boiling it for an hour..."
Boiling meat for an hour does NOT sterilize it. For proper sterilization (making it shelf stable), you need to process in a pressure canner at 10 pounds for 75 minutes (pints) or 90 minutes (quarts). Processing time is the same for hot-pack or cold-pack.
... there are some pretty high-order animals here on Earth that can live in saturated brine solutions. The imaginatively named Brine Shrimp come to mind. They can even survive in quite cold temperatures. (Yes, I know, the "brines" on Mars aren't necessarily purely NaCl in water. They aren't here on Earth, either. And yet life seems to find a way ... ).
I was thinking something similar. Given the terrestrial environments life has been found in, it seems presumptuous to dismiss the possibility out of hand. This may be an environment outside the known parameters, but unless we have multiple examples of such environments here on Earth we can’t say terrestrial life couldn’t survive it, just that it hasn’t had a chance to.
Is this environment that much harsher than the brine lakes under the ice cap in the Antarctic?
I wouldn't expect terrestrial life. However, I am questioning the statement that Martian brines are "unlikely to play host to anything that looks like life as we know it". I rather suspect that if any life is found, it'll look and act an awful lot like life here on Earth ... Including being oxygen, carbon, hydrogen and nitrogen based, with a sprinkle of calcium and phosphorus, a dash of potassium, sodium, sulpher and chlorine, a bit of magnesium and a small pinch of other contaminants.
There are very few places on earth where life hasn't arrived.
Selection happens when there is pressure to survive so there is no reason why anything on earth would evolve to live in an environment which doesn't exist on earth.
Without looking into Scientific papers you can get an idea at
We will give them 212° Fahrenheit (1000° Celsius) is an unfortunate typo
Icon in homage to D. radiodurans
So life could be there but it's unlikely that the first humans on mars will be able to catch it and eat it. But let's face it, who thought that there could be life living deep under the ocean on volcanic vents? The idea was thought to be just crazy 50 years ago - but not today.
Biting the hand that feeds IT © 1998–2020