Opal is the gemstone for those born in the month of October, but Mars scientists may claim it as the treasure of 2008. Inside the largest canyon in the whole solar system, opal minerals stretch in a pinkish cream swath, just to the right of a crater filled with dunes.
You may dream of jewelry, but this discovery has far greater value. Finding opal in the canyon means that water was on the surface of Mars about 1 billion years longer than previously thought. The long-term presence of water is essential to life as we know it. Maybe the canyon had rivers and small ponds for a few billion years. Could it have been an environment for life? Knowing that would be worth more than gold!
High-Resolution Imaging Science Experiment, Mars Reconnaissance Orbiter
Image credit: NASA/JPL-Caltech/University of Arizona