17 noviembre 2008

Early life in Mars

If you got here looking for words about life in Mars at present times, you got to the wrong place, this post is about investigations have been made around early life in Mars in the period between 4.5 and 3.5 billions years ago.

This post is based on the notes I took during a speach given by Frances Westfall from CNRS Orleans-France on 11th November in Cosmocaixa, Alcobendas, Madrid, Spain.

Why are they researching whether there was life in Mars ages ago? Why is it relevant? Is there any evidence? Any indication? If there was, why did did it disappear? .... It looks an interesting list of questions, right? Don't have expentations, most of then are still un-answered.

First traces or evidences on Earth are aged 3,5 billion (american billion, a thousand million) years ago but those traces already show a non-primitive form of life, it must be an earlier life according to the scientifics but nothing older has been found because of tectonic motion destroyed any evidence of such period of life. Scientifics, of course, are not happy with that and they developed a theory - that is why they are scientifics :-)

Considering that Mars and Earth are about same age - in cosmologic scale - and they had a similar geological childhood, it could be likely that life arose in Mars, developed there and, then, disappeared.
It is also apparent that Mars used to have quite a volcanic activity, represented by Olympus Mars volcano sized in 600 Km diameter and 26 km height, enourmous compared to the largest on Earth. In spite of such volcanic activity, the tectonic motion never appeared in Mars so evidences and traces of early life could be there, not on the surface but deeper.

One more relevant piece of information. Early forms of life were, obviously, very primitive, small and, as a result, extremely difficult to detect, in fact there are only three places on Earth where early life has been found and properly analysed. Once the trace of early life is found, one can collect the fragment and analyse it at the laboratory - this is the way it is done on Earth - or, alternatively, one can bring the analysis machines to the place where the evidence is located.

So, what are the scientifics planning?
They are planning a mission to Mars to locate traces of early (4 to 3,5 billions years ago) life on Mars, drill some meters, extract the rock fragment and, then analyse it on-site with the a machine that will be brought there for that specific purpose or, as second option, return to Earth and analyse it here. It must be said that a return mission has not happened yet.
Plans for on-site mission are around 2015 and return mission 20025. So, I hope, we all will remember this post when the announcement of early life discovery on Mars will be made by TV then.

No hay comentarios: