I do have a few questions:
1. Have you looked into Ad Astra's VASIMR engine? They claim it would reduce the trip from the standard 6-8 months down to 39 days. NASA will be testing it on the International Space Station in 2015 I believe.
2. I know liquid-fueled thorium reactors are still not viable, but if they become viable would you consider building one on Mars?
3. What are the upper age ranges you are looking at for astronauts? I know you've mentioned that the lower age limit might be about 25, but I will be pushing 40 by the time the first trip to Mars is planned. Will that be too old? Or by the time the last mission is going I'll be about 50; is that too old?
4. You have said that you will encourage the astronauts not to have children when they get to Mars due to health and safety concerns, but accidents happen. What would it take for you to consider it safe for astronauts to start having children? Short of taking lab rats and other animals and studying the reproductive effects of microgravity or the low gravity of Mars, how are you going to determine the safety of or true settlement size needed for procreating and raising children on Mars? For that matter, what if people going to Mars form intimate relationships?
5.Are there any plans to intentionally introduce Terran lifeforms to the Martian environment, or attempt to breed organisms that can survive on Mars (e.g. photosynthetic single-celled organisms, high altitude or high latitude grasses, etc.)? In other words, what about beginning the terraforming process? This doesn't really require any advanced technology that is not already commercially available to begin experimenting with introducing some organisms.
6. You have said you want the astronauts to be training during the ten years leading up to the missions. For the first mission in 2023, I will probably still be in school for at least six of those ten years, and may have to do further training after that (all of which would be in training that could be incredibly useful skills for a small crew living on Mars). How would that affect my ability to qualify for the first mission?
7. Current astronauts are limited to being no taller than 6',3" (190 cm). Is there going to be a similar height restriction for this mission?
8. What about internet access and other forms of electronic communication/data transfer, especially for research and entertainment? Will they be available on Mars?
9. If a properly designed spacecraft were built that could be easily refueled, it could be left in orbit and the lander could touch down. That way the only thing needed for a return trip is a way to get into orbit again, and someway to generate fuel for this. (The VASMIR engine could really be useful for such a plan.) Would this idea be something you would consider?
10. What about doing a smaller version of Biosphere 2 or the Eden Project on Mars? It would be really nice to have something like this for peace of mind, not to mention food production and oxygen generation.
11. What about compost or other forms of recycling wastes? This could go along ways to helping provide the nutrients needed to sustain plant growth. What type of facilities will you be sending to support this?
12. How are you going to ensure the long-term psychological health of the crews? Considering confined environment psychology and the issues that have arisen in the past with similar situations (accidental or intentional) here on Earth, how do you propose to protect against this on Mars? I know it would be good for TV drama, but this could be disastrous, possibly lethal on Mars.
13. Are you going to implement an exercise regime similar to what astronauts in orbit go through for those living on Mars? With the reduced gravity there is still a chance that there will be bone demineralization and muscle loss.