Mars covered in toxic chemicals that can wipe out living organisms, tests reveal
Source: Guardian
July 6, 2017
Discovery has major implications for hunt for alien life on the red planet as it means any evidence is likely to be buried deep underground.
The chances of anything coming from Mars have taken a downward turn with the finding that the surface of the red planet contains a “toxic cocktail” of chemicals that can wipe out living organisms.
Experiments with compounds found in the Martian soil show that they are turned into potent bactericides by the ultraviolet light that bathes the planet, effectively sterilising the upper layers of the dusty landscape.
The most hospitable environment may lie two or three metres beneath the surface where the soil and any organisms are shielded from intense radiation. “At those depths, it’s possible Martian life may survive,” said Jennifer Wadsworth, a postgraduate astrobiologist at Edinburgh University.
Read more: https://www.theguardian.com/science/2017/jul/06/mars-covered-in-toxic-chemicals-that-can-wipe-out-living-organisms-tests-reveal
Wow, this is a game-changer for all those wanting to visit or live on Mars.
= new reply since forum marked as read
I didn't show you this picture and we don't even know each other...
A picture like that can't be faked
We live on a planet that offers a toxic environment we don't think about. My friend once wondered how much radiation we have been exposed to by the time we are in their 30's. If toxic chemicals and other materials weren't naturally included in our environment, would carbon-based life ever die? On top of that, mankind has found ways to intensify what the planet already has. And even more, we are bathed in space radiation every single day. Critters from Earth would probably thrive on Mars 
"Life...will find a way."
--Ian Malcolm, "Jurassic Park"
Consider the sea anemone. One of the nastier pieces of work in the briny deep, the sea anemone has exactly one job: to fire venom-tipped darts at any passing fish small enough to fit in its mouth. The venom paralyzes its victim, enabling the sessile sea anemone to drag it to its doom.
Well...any victim but this one.
Clownfishes are absolutely immune to sea anemone venom, and use fields of sea anemones as a defensive tool - anything that might want to eat a clownfish has to get past the anemone first, which it can't do.
Or take this lovely little species of bacteria, Thermus aquaticus:
T. aquaticus thrives at 70 degrees Celsius and will survive at 80 degrees Celsius. (You, however, cannot.) This bacteria was discovered living in geyser reservoirs in Yellowstone National Park. Before it was discovered, scientists believed no living being could survive above 50 degrees C because one of the critical enzymes organisms need to survive quits working in most organisms at 50 degrees C. No one told T. aquaticus.
Here's my point. We simply do not know enough about life in the universe to rule out the possibility that perchlorate respiration exists. On earth, perchlorate salts are used as rocket oxidizers, and we have many species that die when exposed to oxygen. Why COULDN'T there be organisms on Mars that breathe perchlorate rather than oxygen?
Looking at it another way...given what perchlorate is used for on Earth, if we can find ammonia and aluminum on Mars, and mine enough perchlorate to meet the need, return spaceflight from Mars may be possible.
