I hope that video streaming for future interstellar conferences will be standard as I suspect many people outside the US can't attend. Some comments which came to mind after watching the videos:
- Not much was said about the space radiation problem for humans (it is estimated a human can only survive up to 2 to 3 years in space in a standard spacecraft). This problem will have to be solved before long human deep space missions are considered. Otherwise probes will continue to do most exploring for us for the foreseeable future. Even a trip to Mars several months long poses a radiation health issue for the crew. The passive and active shield systems for the spacecraft will have to protect at least the human habitat in the spacecraft from dangerous space radiation and bring it down to at least 30mSv/year (workplace maximum radiation dose standard). At sea level, cosmic radiation exposure is 0.3mSv/year, at an altitude of 3Km it is 1.2mSv/year in Europe. There is a rundown on the problem discussed here. For any future manned interstellar mission (including deep solar system) this is a high priority research topic.
- As mentioned previously in this blog, it is unlikely interstellar travel will kickoff unless a replacement for chemical rockets is found to place hardware from ground to Low Earth Orbit. The expected large amount of hardware required for interstellar missions will make the cost too prohibitive. So although it is interesting to discuss interstellar missions which most likely won't happen for at least another 50-100 years, unless the more pressing problems are solved first, it is unlikely there will be interstellar missions for a very long time. Space Drives or Gravity Control Propulsion would be a game changer, this should be another high priority research topic. Even if a space elevator is built here on Earth, it doesn't solve the problem for Low Planetary Orbit to ground and vice versa transfers on other planets.
- Warp Drives and Wormholes: as mentioned previously these are allowed in General Relativity only but denied by Quantum Physics. Experiments related to these will continue to yield negative results. General Relativity is a classical model of the background dynamic quantum vacuum which works very well at describing Nature however the research so far hasn't shown how Quantum Physics would allow warp drives and wormholes to be physically possible.
Update: There's an interesting wiki article as well on the space radiation issue worth a read: Health threat from cosmic rays.
Update: The Space Elevator Conference is on at the moment in Seattle. Last time I checked the state of the art fabrication process could only make carbon nano tube fibres a few centimetres long in the lab. These fibres need to be yarned into a cable long enough to reach geosynchronous orbit for the space elevator tether. A steel cable doesn't have enough tensile strength and at a length of 35786 Km will just break. Interesting to keep an eye where they are up to. To me this is Plan B if Space Drives or GCP turn out to be unviable because space elevators require a considerable amount of infrastructure to work while a hypothetical GCP enabled ship would not and would be free to manoeuvre around a planet (a big advantage). Also keep an eye out for the Skylon Project (Plan C), cargo transport is limited but the vehicle itself is quite neat and is really a big improvement over the Space Shuttle if they can get it working. The space elevator and the Skylon Project (not quite) are currently the only viable alternatives to chemical rockets regarding getting hardware into orbit from Earth that are feasible.