[troutman]

Pretty panoramas: Curiosity's scenic views of distant hills

http://www.planetary.org/blogs/emily...sols50-51.html

First science reports from Curiosity's APXS and ChemCam: Petrology on Jake Matijevic

http://www.planetary.org/blogs/emily...logy-jake.html

To a geologist, that string of four elements -- sodium, aluminum, silicon, potassium -- immediately makes one think "feldspar," and a particular flavor of feldspar (rich in alkali elements sodium and potassium) that I don't know if we've ever seen on Mars before. It's the commonest rock-forming mineral on Earth, the pink or opaque white or sometimes gray material in granite countertops. That, combined with the information that the rock is relatively low in magnesium, iron, nickel, and zinc, told every geologist listening to the call that Jake is a rock that formed from a rock melt that evolved, changed, from a straightforward melted Mars rock. (Or, that it was a melted rock made of material that had gone through some such process.) It's a rock that formed through processes that we know in Earth geologic environments, but not one we've ever seen on Mars.

The journalists on today's teleconference pushed Stolper hard for statements about what this rock says about Mars' history, about the environment that prevailed when Jake formed. His answers likely dissatisfied them; they were equivocal and noncommittal. But that was appropriate. The news today is that in investigating a common rock type (basalt) to cross-calibrate two instruments, they found an uncommon composition, something unique, something that requires a dynamic, evolving geologic environment of an as-yet-unknown nature, something that opens up a new space of possibilities for types of igneous geology that can be imagined for Mars' past.