Sol 116 saw a news conference at the American Geofysical Union’s Fall Meeting in San Francisco, California. The big news we all had been waiting for turned out to be no more than an exhortation to be more patient. As Science takes time to do it right and precise. And right now any organics measured by SAM might be either of three things:
- inadvertently taken from Earth, even if we tried to clean Curiosity really well
- raining down from Outer Space onto the surface of Mars (by meteorites)
- formed on Mars in the environment that was there, so indeginous.
Right now they don’t know.
Patience and they will try to find out by many more tests and measurements.
That was a bit of a downer, after waiting for several weeks to hear what the ‘one for the history books’ that John Grotzinger talked about during an interview
150 reporters and bloggers were present. The most spectacular news was that we landed on an ancient riverbed. So flowing water on Mars was once again proven.
The saga of the Mars rover Curiosity was the opening press conference at the AGU meeting.
Michael Meyer – project scientist started off with telling us that Curiosity landed on an ancient riverbed and that was the first box on a list of what Curiosity was supposed to do to be ticked off by the Curiosity team. Then Michael went on to talk about Rocknest and the measurements there. The Curiosity rover took many scoops at Rocknest for a soil analysis at Rocknest. This did give us an unprecedented look at the diversity of the soil of Mars.
The other people present to talk about the Curiosity mission are:
Ken Edgett, PI van MAHLI from Malin Space Sciences Systems
Ralf Gellert, PI of CHEMIN of the University of Guelph
Paul Mahaffy PI of SAM, Goddard Space Flight Center in Maryland
John Grotzinger, PI of the Curiosity mission.
Ken Edgett starts with showing a ‘self portrait’ of Curiosity by the rover arm, while standing at Rocknest where Curiosity was parked for 6 weeks and scooped sand 5 times. The 5th scoop is what Paul will talk about. Scoops can be seen inside by the MAHLI. The sand was very fine as what we were looking for. grain size is about the same size as artificial sweeteners. So smaller than suger, but larger than flour. Some sand is about the same size as the coarse salt on a pretzel. (One wonders whether Ken had breakfast before doing this conference as he is talking food all the time.)
Ralf Gellert talks about what the APXS saw. The team wanted to have ‘ordinary’ soil. Nothing too unusual as it wanted the soil sampled to be average. The measurements were made inside the scoop pit in the sand and also inside Curiosity with the chemical laboratory in her belly. Compared to the soil found by the MER rovers we see much overlap of what we found at their regions. Therefore we conclude that this soil at Rocknest is average for Mars.
Paul Mahaffy talks about that both laboratory instruments inside Curiosity, Chemin and SAM, got their first measuring jobs on Mars. The volatiles released from the soil by ChemCam did not give us organic compounds, even if we do see organic compounds in the results of the tests on Mars.
So either Curiosity did not land on Mars clean enough to measure Mars as she finds it, which could mean that the Planetary Protection rules for her mission are perhaps not met by this Mars rover, or we don’t know what to think about this second announcement of ‘yes, we found organic compounds, but please disregard them’.
Water vapor was produced by SAM’s test. CO2 ofcourse was found as the atmosphere of Mars is 95% CO2. At Rocknest the Deuterium to Hydrogen ratio is much heavier than Earth Water. There is s seasonal change in the ratio of Deuterium to Hydrogen on Mars. The sample is really oxidizing. The Oxygen could come from a Chloride. We don’t know yet which compound exactly. Also Carbon was found at Rocknest. They are trying to make sure that the Carbon measured is really from Mars. The Carbon could be from inorganic origen. (But also from organic origen, or Paul Mahaffy would not mention this).
John Grotzinger starts his part of the presentation by stating that we all have to have patience if we want to know what Mars is made off. The team made sure that the material was really from Mars but also that it was not sticky (e.g. by water mixed into the soil) and would clog the inside of the rover. This soil was a practice or proving round for the instruments. All what John is telling us is demonstrating to us one thing for certain:
They are being very conservative, it seems.
I understand that they want to make sure that Curiosity is measuring the soil on Mars. And not just the organic materials that fall to Mars with meteorites and that must be part of the soils that the wind blows around Mars. John tells us that we must be sure that it is nothing else, but really the measurement of what we scooped.
Also Curiosity and all its instruments is a very complicated machine with a ‘ten-thousand page manual’ according to John. So far we have only tested our ‘car’ on Mars. The future will tell us whether we have something truly earth -shaking found by Curiosity. In short: Science takes time and we need to have patient to hear what really comes out of all the science done by Curiosity.
How are you going to figure out whether these measured organics are indigenous to Mars? is the first press question. John tells us that they will make a measurement and we know that the instrument is performing very well. However even if we tried to get it as clean as we can before we send it to Mars. However, something might have hitch hiked to Mars within the Curiosity instrument set. Next to that is the possibility that organic molecules might be from outer space raining down on Mars. We need to make sure that what we measure is something that was formed on Mars in the environment we are sampling.
Ofcourse many other questions came from the press, and also from the general public via chat, still this was the gist of what this press conference was all about. Regarding organic compounds on Mars, stay tuned as this mission is not even 4 months old, at least 20 more to go for the main mission, and perhaps many, many more months, even years after that.
Self portrait by the Robotic Arm on Curiosity, while she was parked at Rocknest for 6 weeks.