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To: SunkenCiv
Minutes? Try days. Apollo 11 lasted 8 days, Apollo 17 lasted 12 days.

On the surface of a body, you solve the problem by going underground if the stay will be lengthy.

The problem with a manned mission anywhere other than the moon is your trip times are measured in months using chemical rockets. Basically, any serious proposal for going to Mars should involve nuclear propulsion to make the trip time and risk more manageable. As well as nuclear power on the surface because making consumables (air, water) on the surface will be necessary.

Also, it should be a semi-permanent self-sustaining outpost, since not just the travel time but the travel cost is exorbitant.

I don't see it in our national will anytime soon.

11 posted on 10/15/2017 6:32:10 AM PDT by hopespringseternal
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To: hopespringseternal
Days? Try minutes -- as I clearly stated, the Apollo missions' trip through the Van Allen Belts took minutes, and that's when they were in the most concentrated areas of radiation.

Nuclear propulsion is being studied by SpaceX, supposedly per Gwynne Shotwell, but it has the same limitations that it has always had. It's only good for shuttling things from orbit around one planet to orbit around another, requiring bigtime chemical propulsion boosters to get it to orbit in the first place, because the weight of the system offsets any potential increase in specifiic impulse. The only advantage if may offer will be to push probes to other star systems, yet it would still take a few lifetimes to accomplish the journey.

The argument that use of nuke prop would reduce consumables is found everywhere, but it is spurious, because that's such a tiny amount of the required payload. Cargo (such as habitats, greenhouses, and such) in larger quantity doesn't need to be sent with (or wait to be sent with) human passengers, nor does it have to get there on a strict timetable, or even wait for the favorable position of the two planets.

16 posted on 10/16/2017 1:08:28 PM PDT by SunkenCiv (www.tapatalk.com/groups/godsgravesglyphs/, forum.darwincentral.org, www.gopbriefingroom.com)
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