New Mars Forums

Heaps more stuff added. Some very interesting discussions going.

Why not throw in your own thoughts? Check us out at: http://cleanslate.editboard.com/topics-f2

Hope to see you there!

I'm pretty sure the human body can't tell the difference between gravity created naturally or artificially. Physically, they are both identical. Unless your talking about short radius arms. But for sufficiently long radii; I'm pretty sure the body will find it indistinguishable from natural gravity.

What about using compressed CO2 in combination with an RTG? The excess heat could be used to expand the CO2 for more efficiency and power, while cooling the RTG at the same time without the need for large radiators. The CO2 would be compressed with an electric compressor running off the RTG. Sounds pointless but the benefit would be a more compact RTG system and better power density.

I imagine average combustion pressures would be much higher though.

Has steam power been discussed here before?

Wow, I have never heard about this. Do you have any more info on this, SpaceNut? Would it be worth performing a similar experiment on Mars? What sort of information can be obtained?

I'm disappointed that the idea of mars cars powered by compressed CO2 is so quickly dismissed. Powering cars with a compressed version of the local atmosphere would be a simple and elegant method of propulsion; if it could be made to work. Is there anyone here that could look into the physics a little further?

Concerning that last comment; is Griffin just trying to scare the US into speeding the Lunar program (or perhaps hoping for re-focus towards Mars), or does he truly believe that China will beat the US?

Alternative Theory (not sure if I subscribe to it, but sounds intriguing):

"The human body will adapt to remain healthy in its environment.

Yes, a man in zero-g will experience muscle and bone loss, and his heart may shrink, but this is because large energy-hungry muscles aren't needed to get around in zero-g. If his body kept these things, what useful purpose would they serve in an environment where it is impossible to fall and you get around by floating instead of walking?

The astronauts encounter problems because the change from full-g to zero-g is so sudden. Their bones demineralize so fast that their bodies have trouble getting rid of the liberated calcium. But they survive the adaption process, and once adapted, live quite healthily in zero-g.

The confusion on this matter arises because the current definition of 'healthy' requires a minimum bone and muscle mass (among other things) based on observed norms, which of-course, are biased towards terrestrial living."

Yeah, but thoroughly testing it on the ground first isn't a bad idea. Better than not bothering at all.

I agree. Considering Zubrins studies, what sort of mission could be achieved using three launches of the Ares V using the pre-developed Lunar EDS as the departure stage?

Perhaps the Lunar EDS could be scaled easily to meet MarsDirect requirements?

cIclops is right. If all goes to plan, flying these Ares-V's should be just as routine as flying the Shuttle has been... We could easily fly 5 of these things a year, more if we consider that they are unmanned (less safety risk).

So the real question is, what shall we do with the excess launch capacity?

Thanks cIclops.

What I intend to find is how far the launch window can be extended if given the option of earth departure at both conjunction and opposition.

The data on available launch windows for a conjunction class mission is excellent. Now I just need something similar for opposition class missions.

My intention is to graphically represent when launch opportunities open and close through the years 2020 to 2040, perhaps by using green and red bands of colour in a linear progression.