- CheMin's examination of Rocknest samples found the composition is about half common volcanic minerals and half non-crystalline materials such as glass. SAM added information about ingredients present in much lower concentrations and about ratios of isotopes. Isotopes are different forms of the same element and can provide clues about environmental changes. The water seen by SAM does not mean the drift was wet. Water molecules bound to grains of sand or dust are not unusual, but the quantity seen was higher than anticipated.
SAM tentatively identified the oxygen and chlorine compound perchlorate. This is a reactive chemical previously found in arctic Martian soil by NASA's Phoenix Lander. Reactions with other chemicals heated in SAM formed chlorinated methane compounds -- one-carbon organics that were detected by the instrument. The chlorine is of Martian origin, but it is possible the carbon may be of Earth origin, carried by Curiosity and detected by SAM's high sensitivity design.
Exciting, but "One for the history books" might have been overstating these findings.
When watching the live feed, they seemed to indicate that they now have a tried and true working scientific laboratory on Mars and this was what should make history. That's what I gathered at least. They've test drove the rovers capabilities and will now "kick the tires" a few more times and head for the hills to do some real experimentin'.
From the scientist's perspective, it is one for the history books, so I don't think he was speaking in hyperbole. I think the problem is that most people will never actually read a history book (beyond college), and thus, they don't have a good perspective on what's historical. Launching a robot to another planet to analyze chemistry is amazing feat; reporting that it worked would be enough to make it a historical mission, let alone that it actually discovered anything interesting. In the future, hopefully these types of missions will be routine; if so, they will all credit Spirit, Opportunity and Curiosity (among others).
I would imagine that some people got a stern talking too regarding the "one for the history books" comment. That said, I also imagine that it has helped more than hurt. We've all been talking and writing about it and wouldn't have to the same degree had the statement not been made. Even now there will be follow up interviews from major outlets only because of the statement. It's a dangerous card to play, and though I don't think it was intentional, they played it well imo. Now they've got our full attention and we all wait with great anticipation for new findings. Interesting times we live in, for sure.