Question

we found out there's water in mars. if we don't find any life in mars will that not be a blow to biochemical theory of origin of life? after all mars and earths were similar at earlier stage of creation.

Answer 1

not necessarily. just as an example - the temperatures on mars vary from -100c to 130c (more or less). this fact pose a problem: both in the extremes itself, and the temp. variation. just think about a bacteria that is used to 37c, and when we are pyrexic - to 40c or so (a mere 3c) it is not as effective enzymatically

Answer 2

Sorry this answer is incorrect, surface temperatures on mars vary from 186K (-87C) to 293K(20C) with the mean being 210K(-63C). there is also life on earth that can quite easily survive these temperatures. there are bacteria deep within the earths crust, miles down in solid rock that matabolise single molecules in decades. if mars does not contail life then it could be justfied with the reasoning that mars may not have had the correct chemicals in its oceans at the correct time for the formation of early life.
this would not disprove the biochemical theory, it would just mean that there are factors that were present on earth not mars.
A very exciting question though, I do hope we see an answer in our lifetimes

Answer 3

by the way you can check the numbers i have quoted on wolframalpha.com search for mars

Answer 4

Not necessarily. Logically, biochemistry requires the presence of water for life to exist, but having water does not mean that life has to exist. So finding an absence of life on Mars or any other planet with water does not invalidate a biochemical theory for the origin of life.

Answer 5

Water is not the only substance needed for life. For us we need carbon, oxygen, nitrogen etc. Some organisms could exist with methane replacing carbon.
Water doesnt equal life, just means we have a component to create life

Answer 6

Some scientists have discovered that organisms can use arsenic instead of... their DNA base I think it was, so now we have to remember to test for arsenic too

Answer 7

Yup arsenic is viable too

Answer 8

there are many theorys in xenobiology concerning different possible ways of life forming, including nitrogen instead of carbon based life aswell as the examples give above. If you have interest in the subject google xenobiology