A Response to the "Life on Mars" Question

Scientists are trained to be skeptics. You really want to see all of the facts before you reach conclusions and, of course, you tend to want to reach your own conclusions and not accept those of others. So, I express some skepticism. This is not the first time people have claimed they have found evidence of life in meteorites or organic molecules that suggest biological activity.

Whether or not this will stand the test of time is what science is all about; it has to be repeated again and again. Very rarely does a scientist publish a set of data without having repeated it, sometimes 100 times or more. So this is certainly very exciting data, and is the type of thing we were not surprised about. Most people that work in the area of exobiology really believe that we are not unique in the universe.

There is no reason to suspect that Mars did not have the proper conditions for life to have evolved. Wherever you see water, you begin to think that life is possible. When you study the extreme environments here on Earth, you realize that almost every environment is populated. So the ability of life to adapt to these far-reaching environments is just incredible: from the boiling hot springs of Yellowstone, to the rock crusts in the arctic dry valleys, to the depths of the ocean.

About the only thing we haven't proven is whether or not organisms can survive in an aerosol (the clouds). That became a limiting factor for the Jovian (Jupiter) situation. If life was going to evolve there, it was going to evolve in an aerosol environment. But part of the difficulty on our part is devising experiments that can even measure whether or not life can exist in these aerosols because here on Earth gravity comes into play, once again.

So I don't think exobiologists would be surprised that life could exist in an aerosol environment, and it's not ruled out. But to prove it, they have to go back and find some evidence of real cell structure, perform experiments more than once on many cells, and hopefully, find other meteorites of similar age that they could use for comparison.