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Tue 4 Jan, 2005 07:05 am
Let's assume there is great urgency to establish a Mars colony by 2012. Even a small, high risk, permanent colony by 2012 on Mars, means we need to start cutting metal soon. The craft needs to be bigger and more massive than the systems that took 12 men to the moon. We have few improvements that have proven reliability other than the solid booster rockets, and better computers. Unproven technology should be in two tugs that can shorten the trip but allow the main craft to land safely on Mars, even if the tugs fail.
Final assembly and fueling likely needs to occur at the ISS = International Space Station even though this is high risk for the ISS and compromises most of it's functions. The ISS is not stressed to allow blast off of a large craft, so launch means drift slowly apart for hours, before lighting the main engines briefly. The first of two unmanned nuclear powered tugs can then attach by a long tether, and begin towing the manned craft toward Mars. The next day the second tug is attached by long tether. If this works well, they will 2/3 of the way to Mars in perhaps 100 days. The tugs will now begin decelerating the main craft until about one hour from touch down (we will not orbit Mars) One tug will be towed by the main craft to the surface of Mars to be used as an energy source for the colonists. The second tug will pull on the tether to keep it away from the flame of the main engines which are needed to further decelerate and facilitate a gentle landing. The 2nd tug will cut loose about 100 miles above the surface of Mars, do a sling shot maneuver to allow it to reach escape velocity of Mars, so it can travel to it's next assignment.
A nuclear reactor with no shielding on one side is an ion engine. It can produce considerable electricity which can run a second ion engine, and send a small amount of power over the long tether to the manned craft. Please comment, refute and/or embellish. Neil
I don't believe a sustainable colony could be built in that time frame. Just getting there in one piece is a major obstacle. Look how much trouble they have maintaining a rinky-dink space station. I don't see it at all, under any circumstance.
An ion engine cannot produce enough thrust for planetary takepff and landing. They do have very high specific impulse, though, and are currently in use for satellite station keeping. Nuclear heat exchange engines would be excellent for this mission, though. One was built and static tested as Project Nerva in the 50s. I believe it may have been discontinued by Congress for budgetary reasons.
edgarblythe is likely correct, but we won't know what is possible unless we have the intense motivation to try. Some of the best technology is likely secret.
I don't think there is an upper theoretical limit for ion engines, but I did assume the ion drive tug would begin it's job in low Earth orbit, and that the manned craft would have to tow/ drag/ dangle one of the tugs to the surface of Mars, where it would be used as an energy source for the colony. Since the 50s design is a nuclear reactor, it may be practical to combine the best of three systems into the tugs. The system I heard about used graphite to slow the neutrons in the reactor and as the reaction mass. I suppose the output fell off as the graphite was lost from the engine, so the Mars colonist would eventually (at considerable radiation exposure) need to replace the graphite. Ordinary carbon soot should surfise for a stationary reactor, if a deposit of graphite was not found on Mars.
If I am thinking of the same project, it polluted Earth's atmosphere with lots of radio active isotopes, so it could now only be operated, unmanned in orbit or higher. This makes testing difficult, but not impossible. The long tether is to protect the manned Mars craft from the radiation from the poorly shielded reactor. Neil
Quote:edgarblythe is likely correct, but we won't know what is possible unless we have the intense motivation to try. Some of the best technology is likely secret.
But nobody is trying to accomplish this
I didn't say I was against a colonizing effort, however.
Seven years to launch and land on Mars? Not going to happen. There are no set plans to even return to the Moon at present (in spite of a sort of commitment from the President in Jan last year).
The emphasis will be on the military applications of space from now on. Check out the Federation of American Scientists at:
goto
At least i won't settle down their....just a tour is OK..
Hi Mr Stillwater: I agree, but if we plan to go in 2019, not much will happen until 2012. We humans need to motivated by an unrealistic deadline. I also agree that there is presently a shortage of motivation for the public, the politicians and even the aerospace industry, which stands to make huge profits.
When and if we go to Mars, the brainstorming done far in advance will be partly what makes the colony a success. Colony has the big advantage that plans for a return trip can be made long after the colony is established. Unmanned probes prove that we can start delivering supplies to the colonists on short notice. Neil
I'll go if there are no republicans or rightwingnuts...and I'm sure they'd be happy to pay my way.... :wink:
just so that you know, martian atmosphere cannot provide enough oxygen yet, and how do you expect us to supply oxygen for years which is how long the journey is probably gonna take.
Welcome to able2know yjxbigrick: I agree, even genetically modified humans likely cannot breath the atmosphere of Mars, and with present technology it will take perhaps two years to reach Mars. Operational tests however are probable this year on propulsion systems that will get us to Mars in 200 days. Extra oxygen will be one of the larger items in the supplies needed. On Mars, oxygen can be extracted from water, assuming some can be found near the colony, and there is sufficient energy.
The poles of Mercury may be a better places for colonys, But the Mercury trip requires twice the propulsion energy and/or twice the time of Mars. Neil
Well Mercury and Venus are out of the question in the foreseeable future, but mars can be colonized. Yet its still to big a leap to reach 2012, i mean weve had the moon there and we've had men there, and we still havent colonized it. Not to metion(said before) the type of money needed. With only 3 contries even capable of spaceflight(China, America, and Russia) not a chance. China just launched, Russia not enough funds to do anything that big/unprobable, America spent in Middle East. I mean even now the Russian and America space programs are in decline, since where else are they.
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