Bert posted:

Let me ask you this does Mars atmosphere
have an ozone layer?

Not like the Earth's. There is a small amount of Ozone in the
atmosphere of Mars (about 0.03 ppm at the surface), but its shielding
effects are fairly small.


Without a ozone
layer there is no protection against ultraviolet radiation.

Life originating in seas and oceans might also have some protection by
being under water.

Has the Martian atmosphere some oxygen?

Yes, it does, although again, the amount is fairly small (Martian
Atmospheric composition at the surface: 95.32% Carbon Dioxide, 2.7%
Nitrogen, 1.6% Argon, 0.13% Oxygen (diatomic), 0.03% Water Vapor, ect.).


--
David W. Knisely
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

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