I removed the part "Early in the history of the colony, crews would likely rotate, in a similar manner to a moon base or the ISS", because I find it extremely unlikely to have a regular personnel space travel between Earth and Mars. With the currently available transport technology those journeys consume vast amounts of money. Manned space flights cost several times the money compared with unmanned. With the same effort a young colony can be supported with so many things to make life easier. So, I am really in doubt about frequent manned space travel. It would strongly decelerate the development of the colony. -- Rfc 06:25, 18 August 2008 (UTC)
Rotating the entire population of colonists (How many in an early colony?) would not be possible. Scheduled resupply flights would be launched every 2-3 years. Since we are bringing equipment to Mars, and we want to return large amounts of samples to Earth, we could make use of this to transport people to Mars. The transport systems would be reusable, and rocket launches would only be required for fuel. Mars Landers could be made, at least in part, on Mars, And fuel for the return would almost certainly be made on Mars. Do not think of space travel as a Hi-Tech no-no. Think of the apollo spacecraft, which used less computing power then a pocket calculator. Wouldn't a pnuematic computer be up to the task? I am saying, maybe, 5-6 people being transported on an irregular basis. T.Neo 08:04, 18 August 2008 (UTC)
- That's an interesting concept. Maybe you can describe it in detail in a separate article. Such a transport could possibly swing between Mars's orbit and Earth's orbit, which requires rather little fuel. The lift from Earth's surface and the lift from Mars's surface into orbit are really big parts. Another really big part is keeping the travelers alive during the interplanetary journey (food, drink, air, radiation, zero gravity, ...). The transportation of 500 kg of living people requires approximately 10 times the mass of additional life support machinery and additional shielding. So, you have to carry 5000 kg. In other words, the transportation of people is 10 times as expensive as the transportation of samples. Maybe even more, I do not know the exact factor.
- If I would go to Mars, I wouldn't want to return to Earth and leave all that I have built there behind, risk another dangerous space flight, suffer from the stronger terrestrial gravity. For me, the settlement on Mars would be a new home, where I can build up a whole new world, just like the settlers on the American continent a few hundred years ago. Most of them didn't return to Europe, too. -- Rfc 16:50, 18 August 2008 (UTC)
Maybe colonists won't return, but scientists/geologists might want to "stop by" for a year or two, and make use of the existing base to do their research. Here is a mission plan for those scientists:
- One launch atop a Ares V class rocket puts the habitat, tether, etc into LEO.
- One launch of an Orion CEV. The CEV docks with the habitat.
- One launch of the Earth Departure Stage (EDS), derived from lunar missions. The EDS is docked with the habitat module, on the other side of the CEV.
- The EDS burns and places the Habitat/CEV on a Hohmann transfer orbit towards Mars.
- After the burn has ended, The tether unfolds and spins up the habitat to martian gravity, using the spent EDS as a counterweight. The habitat is inflated and "flat pack" walls and floors are set up inside. Hopefully the CEV LIDS dock can withstand 0.38g.
- Upon Mars arrival, the EDS is reeled back to the Habitat and the whole arrangement aerobrakes into Mars orbit. (It would be easier to cut the EDS loose, But I am thinking that some fuel might be left inside, useful for Trans Earth Injection.)
- A lander is launched from the colony to meet up with the Habitat. Fuel from the lander is pumped into holding tanks and/or the EDS. The lander lands near the colony, and the scientists meet up with the colonists and explore Mars.
Cargo is unloaded and utilized by the colony.
- After two years, the scientists launch back to the Habitat. They ignite either the EDS or another engine, and fly back to Earth, again using the EDS as a counterweight.
- Upon return, they cut loose the EDS and aerobrake into Earth orbit. The CEV returns the crew to Earth while the Habitat awaits a new mission.
- Sebsequent missions only need a new EDS and CEV, wth expenditure the same as a lunar mission.
-I dont like Project constellation at all, and I would much rather like to see DIRECT being adopted by NASA. The lander will have to be mainatained and repaired on Mars, but would be lo-tech, and would be kept inside a sintered regolith structure or a cave to keep it away from dust and radiation. The Habitat would be repaired and replenished in LEO, by an unmanned "cargo" CEV developed for flights to the ISS. An Aldrin cycler may seem a better bet, however it requires a massive presence on the Moon and is a waste of vital lunar ice. Mars colonists must be people like you, who want to colonize Mars. Not people like me, who just want to go there for a week, enjoy the view, pick up rocks and return home. T.Neo 08:04, 19 August 2008 (UTC)