April 17, 2011
Organics on Mars?
The basis of this article is that the Phoenix lander may have evidence supporting the existence of organic molecules on Mars. For the past 30 years, we have assumed there to be no organics at all, following the Viking lander's gas chromatograph/mass spectrometer experiment. The experiment started by heating the Martian soil sample to 500C, high enough to dissociate any organic molecules present and detect their constituents as gases. The only thing this experiment found, however, was chlorine compounds, thought to be remnants of cleaning fluid from Earth. The Phoenix's discovery of perchlorate at the Martian north pole challenges this long held assumption. Apparently, when heated, perchlorate dissociates into compounds that destroy organic molecules, explaining the results of the Viking's findings back in the '70s. I don't think this is reason to assume Mars has organics, but rather it just negates the negative findings of the Viking mission. The 2011 launch of the Curiosity Rover is going to search again for organics by introducing liquid water to the soil sample. This could be an important mission if it can detect simple organics like DNA or RNA or simple proteins.
Posted by rborden at April 17, 2011 01:34 PM
It seems to me that the Phoenix mission really can only counteract the negative results that the Viking experiments found. Overall, after we thought that the organics found in the soil was due to chemical, and not biological, reactions, the outlook for life on Mars was very grim. If the Phoenix mission can continue to find more optimistic evidence, such as the ice layer that it has already found, the 2011 launch could potentially seal the deal for whether or not life is to be found on Mars.
Posted by: sekoch at April 18, 2011 01:23 PM
I agree that this should not be taken too seriously as evidence of organics on Mars, because it simply explains and contradicts the Viking findings. I think that it will be hard to convince people of organic compounds on Mars, because just like the findings of the Viking mission there is too much doubt due to chemical, rather than biological, reactions being more likely to cause the results of experiments. However, I think these findings do offer some hope, and that we should continue to search for organic materials on mars, because finding such materials would have a great impact on the search for life beyond earth.
Posted by: emschnei at April 18, 2011 04:37 PMLogin to leave a comment. Create a new account.