Mars Above, Mars Below

With Mars at opposition once again, astronomers around the world will soon be looking up for our best telescopic views of the Red Planet. But next weekend, I and a group of scientists will be turning our gaze downward for views of that alien planet. From March 9 to 11, Death Valley National Park will be hosting the first ever Mars and Mojave Festival, an event designed to showcase research into terrestrial analogs for the general public. The keynote speaker Friday night will be Chris McKay, talking at the main visitor center about NASA's Curiosity rover, currently on its way towards Mars.

For the last five years the U.S. national parks have becoming increasingly well-known as dark-sky preserves where visitors from all over the world can still easily see the full beauty of the Universe beyond our atmosphere. Since 2007 I've been traveling the parks helping to spread the message that "Half the park is after dark." The Mars and Mojave Festival, put on by the park service and the SETI institute, is the natural extension of this effort, showcasing the fact that the astronomy in many parks doesn't end when the Sun comes up. Activities during the festival include scientist-led hikes to Mars Hill and Ubehebe Crater in Death Valley as well as a free expo with Mars rover demos and video programs highlighting the science in the parks.

NASA scientists have used Death Valley and the American southwest as a stand in for Mars for decades. As a school kid in the early 1980s, I still remember seeing Carl Sagan walking around a mock-up of the Viking lander sitting in the Mars-like landscape of the Mojave Desert. Later, as an astronomer at Lowell Observatory in Flagstaff, Arizona, I could see Mars all around me as I went hiking in the Painted Desert and canyon country of Northern Arizona and Southern Utah. In 1999, after working with members of the Mars Exploration Rover team to turn the camera color calibration targets into working sundials for scientific outreach, I recall hiking through a narrow canyon and wondering what all these little hematite spheres were eroding out of the sedimentary rocks around me. A little over four years later when Opportunity got to Meridiani Planum, I found out.

But the search for terrestrial analogs to other worlds in our solar system goes back farther than NASA. When Percival Lowell pointed his telescope towards Mars during the oppositions of the early 1900s, he saw a world through the eyepiece the same color as the red rocks of the countryside around him (and through which I would hike a hundred years later). He noted that the red coloring of Mars seen through his telescope looked very similar to the red color of the nearby Painted Desert when viewed from atop the wooded San Francisco Peaks north of Flagstaff. In the fossilized wood of Petrified Forest National Monument in eastern Arizona he saw evidence of our planet's climate changing as we slowly desiccated just like he thought Mars had done. Today our spacecraft on and around Mars discover ever more evidence for Mars' past climate change, while U.S. national parks provide ample opportunity to see with our own eyes what we think are similar features on Earth. By providing us "ground truth" on Earth we can put what our robotic spacecraft reveal in context. (Hopefully, we will not make as many unwarranted extrapolations from the data as Percival did).

Thanks to work by folks at the SETI Institute and Death Valley National Park this upcoming weekend's festival is, hopefully, the first in a series of events highlighting this research to the general public. Just as night sky festivals like those at Bryce Canyon National Park have been highlighting and popularizing the latest astronomical results, one outcome of this event will be to shine a light on the work of planetary scientists. And what better time to do so than now with Mars in the sky, Curiosity on its way, a movie based on Edgar Rice Burroughs' John Carter on Mars novels set to open in theaters (although minus any mention of Mars in the title) and news of massive cuts to NASA's planetary science budget? Now is the time to see what a hundred years of planetary astronomy has revealed and see Mars by both day and night and in the sky and on the ground.