The importance of water was discussed earlier; however new light is brought onto the subject when thinking in the present. The main problem with water on Mars is the lack of pressure required to sustain liquid water. The decrease in pressure has come about over the course of billions of years as a result of atmospheric erosion and other potential causes. Currently our leading theory is atmospheric erosion; however, it is possible that it is not accountable for all loss of atmosphere. Research has shown that over 3.5 billion years up to four millibar of CO2 along with multiple centimeters of water can be lost due to solar winds. This change in atmospheric pressure was relatively fast and could have caused it to be very difficult for life to continue if it even existed to begin with. All of these problems paint a dismal picture for life on Mars today, but that doesn’t mean it’s completely impossible.
New light has been shed on the possibilities of life currently living on Mars both by our latest rover and by discoveries here on earth. On earth scientists have discovered Achaea and Bacteria in the Earth’s subsurface. These microbes live on hydrogen released from rocks and geothermal activities deep inside the earth (Chapelle). These realizations have given researchers hope that the same types of organisms could exist today on Mars. These are very promising options for life on not solely Mars, but also on other celestial bodies.
Of course there is the question of liquid water which must be realized, but what one will find is that even under a few feet of soil pressures begin to increase greatly. Under these pressures it is possible for water to exist as a liquid, especially in the warmer areas of geothermal activity that microbes could gain hydrogen from. The possibility that some form of life has come to live on Mars deep below the surface is quite likely. We have also found that water is present in the soil of Mars in the amount of up to two percent by weight (Wall).
When discussing life’s existence in places other than Earth, one will find one major issue which is the chance of life actually coming into existence. One hypothesis called abiogenesis describes a series of events which could under very specific conditions form life spontaneously from organic compounds. This hypothesis is one of few which set out to describe how life came to our solar system to begin with. In the case of Mars, one it will be one of the leading possibilities for the origination of life. In that case the chances of life actually coming about regardless of hospitable conditions is likely very low. This doesn’t mean life can’t exist on Mars, there have been more than four billion years for life to start and anything can happen in that amount of time. The situation on Mars is like having a lottery ticket for life, but the chances are slim that you will actually win.
From the information we currently have regarding the presence of past life on...