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Life on Mars?

Some of us feel that it is quite likely that, at least in the past, there has been life on Mars. There are several
observations that seem to point in that direction.
Some years back we got indefinite results from the first measurements that were made on Martian soil. The nutrient
solution which was dripped on the soil contained a mixture of both right and left handed amino acids. Now living organisms
on Earth discriminate between the two. They take the left handed amino acids but not the others. And if, on Mars, we
had dripped two separate nutrient solutions, one with right handed amino acids and one with left handed amino acids, and
if one had been used but not the other, then we might have surmised that their use was through biological metabolism and
not through some unknown chemical reaction. It would also have been nice to know, by which one they chose, whether or
not they might be relatives of ours. A similar nutrient solution was dripped on the soil of Antarctica where the
temperature is similar to that on Mars but where we know that the microorganisms are alive and well. And the results there
were the same as on Mars.
Although at the present time the atmospheric pressure on Mars is so low that the boiling point of water there is colder
than the freezing point, it wasn't always so. Mars must have had a heavier atmosphere in the past or there couldn't have
been liquid water there. And there is abundant evidence that in the past there were both rivers and lakes on Mars. Also,
with a heavier and wetter atmosphere, Mars would have had a warmer climate than it has now.
But perhaps the most convincing evidence that there has been life on Mars is the redness of the Martian rocks. In the
distant past, the rocks on the Earth were not red. The red is largely iron oxide which dates only from the time when our
photosynthetic relatives had succeeded in dumping out enough toxic waste to give us an oxidizing atmosphere. The Universe
at large has a reducing atmosphere, and before the blue green algae and the rest had dumped out all this oxygen, the
iron in our rocks was soluble in water and washed down into the ocean. There a microorganism named Pedomicrobium used the
oxygen from the rocks to oxidize the iron and put it away in the bottom of the sea so that we could make Chevvys and
We know how we got an oxidizing atmosphere, but without photosynthesis, how did Mars? It has been suggested that
through photodissociation of the water molecules in the upper Martian atmosphere the hydrogen was allowed to escape. That
would leave the oxygen behind. But we're closer to the Sun than Mars is, so why didn't it happen here? It's true that on
Mars the hydrogen would have had escape velocity, but so does it here in our upper atmosphere.
When we check again for life on Mars, it is to be hoped that we will separate the right handed and left handed amino acid
nutrient solutions and drip them on the soil at the bottom of the deepest canyon where the temperature should be a little
warmer and where moisture might be a little more plentiful.