Phoenix Mars Mission
"MECA characterizes the soil of Mars much like a gardener would test the soil in his or her yard. By dissolving small amounts of soil in water, the wet chemistry lab (WCL) determines the pH, the abundance of minerals such as magnesium and sodium cations or chloride, bromide and sulfate anions, as well as the conductivity and redox potential. Looking through a microscope, MECA examines the soil grains to help determine their origin and mineralogy. Needles stuck into the soil determine the water and ice content, and the ability of both heat and water vapor to penetrate the soil."
There are two microscopes: "The optical microscope will have a resolution of 4 microns per pixel, allowing detection of particles ranging from about 10 micrometers up to the size of the field of view (about 1 millimeter by 2 millimeters). Red, green, blue, and ultraviolet LEDs will illuminate samples in differing color combinations to enhance the soil and water-ice structure and texture at these scales. The atomic force microscope will provide sample images down to 10 nanometers - the smallest scale ever examined on Mars. Using its sensors, the AFM creates a very small-scale "topographic" map showing the detailed structure of soil and ice grains."
I think this is really smart science: I don't expect that we'll see anything crawling our of the sample, but being able to look at something tells us a great deal about it.
And, I still wonder what we'd have seen, if a microscope had been trained on the soil sample that acted so oddly when a Viking lander dropped it into a nutrient solution. Scientists decided that it was weird chemistry in the Martian soil: not microorganisms. I'm being a bit unfair, but the impression I got was that they figured, since bugs on Earth wouldn't have acted that way, bugs on Mars wouldn't.
Update May 26, 2008:
Another First: Phoenix Lander Descent Photographed
(from Phoenix Mars Mission, used w/o permission)
"Camera On Mars Orbiter Snaps Phoenix During Landing"
Phoenix Mars Mission (May 26, 2008)
"May 26, 2008 A telescopic camera in orbit around Mars caught a view of NASA's Phoenix Mars Lander suspended from its parachute during the lander's successful arrival at Mars Sunday evening, May 25.
"The image from the High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter marks the first time ever one spacecraft has photographed another one in the act of landing on Mars."
- "Phoenix Mars Mission and Another Blog"
(May 26, 2008)
- Phoenix Lander on Mars: Safe, and Sending Photos Home"
(May 25, 2008)
- "Phoenix Receives Final Instructions, Prepares for Mars Landing"
(May 25, 2008)
- "Phoenix Attempts Landing on Mars Tomorrow"
(May 24, 2008)