Last week NASA held a workshop in Houston to begin the long process of selecting a landing site for a future human mission to Mars. Ellen Ochoa, director of the Johnson Space Center, and John Grunsfeld, Associate Administrator for the Science Mission Directorate at NASA Headquarters in Washington, D.C. opened the meeting, and from their remarks it was clear they believe the agency has both the technical ability and the motivation to take on such an ambitious project.
Even though the launch is still about 20 years off, with the first Mars expedition planned for around 2035, the workshop represents a first official step. One of its objectives was to identify what robotic missions need to be sent, and what data need to be acquired, in order for the agency to choose a landing spot. A second goal was to identify what resources would be present at the proposed landing sites and how to obtain them.
NASA officials showed preliminary mission scenarios, while emphasizing that human exploration of Mars is not planned as a single mission, but a series of three to five expeditions, each with a crew of four to six, lasting about 500 Martian days each. All would land in the same exploration zone, or EZ. The plan includes the construction of a surface field station to be located in the center of the exploration.
The crews will live off the land to the largest extent possible, and pressurized rovers would allow them to venture as far as 100 kilometers, or more than 60 miles, from their base for periods up to 14 Martian days. The astronauts will have to learn how to live and work on Mars for extended periods, and will be as independent logistically as possible.
The most important resource for the astronauts will be water, which can be used not only for life support, but also for radiation shielding, plant irrigation, and manufacturing of rocket propelland for the return trip to Earth.
The landing site within the exploration zone will have safety and operability restrictions. It should be located within 50 degrees north or south latitude of the equator to avoid extreme cold and maximize lighting. It also should be free of large boulders and steep slopes, and not prone to large dust storms.
Nearly 50 suggestions for possible exploration zones were presented at the meeting, and future workshops will be needed to whittle down the list. Some of the more remarkable locations were inside Valles Marineris, in Hebrus Valles (my own presentation), where the astronauts could make use of caves, and in Apollinaris sulci, which includes yardangs (keel-shaped crests or ridges of rock, formed by the action of the wind, usually parallel to the prevailing wind direction). Other suggestions included previous robotic landing sites such as Gale Crater or the Viking 1 landing site in Chryse Planitia.
All of the talks from the workshop are now online, and in this clip you can see a NASA animation of how the Mars surface station might look. The video will be updated based on results from the workshop.