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Here's a better plan:
First send a habitat to Mars, with lab and food and all that good stuff. Use a nuclear reactor to power a large Magnetoplasmadynamic (MPD) engine using liquid hydrogen propellant. VASIMR would be nice but it still hasn't worked, MPD doesn't have variable specific impulse but that's Ok. Lithium has been demonstrated with 11,000 second Isp, but the Glenn Research Center is now researching hydrogen. It requires a megawatt reactor, that will have to be built. This would allow the cargo mission to be launched on a single Ares V. Including spiral out of Earth orbit it may take 2 years to reach Mars, but that's also Ok for a cargo mission. Actually land the nuclear reactor with the hab.
Send the Mars Ascent Vehicle as a second launch, sent at the same time as the hab. Send it with an ISPP factory, tiny rover to deploy a power cable to the hab, and a fluoropolymer bag for LOX and liquid methane propellant, with a demployable carbon fibre basket to hold the fuel bladder. This lands the vehicle with the bladder and basket collapsed, reducing its size for the Mars heat shield. The MAV designed as a single stage with oversize fuel bladder so it acts as the TMI stage.
Then lift the Mars Transit Vehicle to ISS with a single Ares V. Include the vehicle with a nuclear thermal engine, and a Nomex umbrella heat shield for aerocapture at Mars. Launch the Mars lander and liquid hydrogen propellant on a second Ares V. Lift the astronauts in Orion, then go.
At Mars the MTV will aerocapture into Mars orbit. The crew lands in the lander, no orbital rendezvous. They of course land at the hab.
After a long stay they as ascend in the MAV. The MAV docks with the MTV and transits back to Earth. The MTV aerocaptures into Earth orbit and spirals (aerobrakes) down to dock with ISS. However, before the MTV aerocaptures the crew depart on Orion for direct entry to Earth.
This leaves the MTV at ISS for the second mission. That starts with a new MAV launch. The first MAV leaves the ISPP factory and power cable rover at the base on Mars so the second one can carry food and supplies. Send it to the first landing site, that is our Mars base.
A single Ares V carries a new lander and LH2 propellant to the MTV. Orion carries the crew, then they go.
This means 4 Ares V launches and 1 Ares I launch for the first mission, 2 Ares V and 1 Ares I launch for each subsequent mission.
If the space tourism guys ever get a reusable space taxi to work, then Orion could be left docked with the MTV as an emergency escape pod. The reusable space taxi could carry crew up and down from ISS.
The ultimate reusability is to build a fuel mine and depot on one of the moons of Mars. Refuel the MTV in Mars orbit. Then replace the MAV with a reusable Mars shuttle based on the DC-XA. That would give astronauts a rocket that could be used for suborbital hops to explore Mars as well as shuttle them back to the MAV. Then each future mission would require only 1 Ares V to lift propellant from Earth, and one space taxi ride. You could even carry food on the MTV and carry it down in the Mars shuttle with astronauts.
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Here's a better plan:
First send a habitat to Mars, with lab and food and all that good stuff. Use a nuclear reactor to power a large Magnetoplasmadynamic (MPD) engine using liquid hydrogen propellant. VASIMR would be nice but it still hasn't worked, MPD doesn't have variable specific impulse but that's Ok. Lithium has been demonstrated with 11,000 second Isp, but the Glenn Research Center is now researching hydrogen. It requires a megawatt reactor, that will have to be built. This would allow the cargo mission to be launched on a single Ares V. Including spiral out of Earth orbit it may take 2 years to reach Mars, but that's also Ok for a cargo mission. Actually land the nuclear reactor with the hab.
Send the Mars Ascent Vehicle as a second launch, sent at the same time as the hab. Send it with an ISPP factory, tiny rover to deploy a power cable to the hab, and a fluoropolymer bag for LOX and liquid methane propellant, with a demployable carbon fibre basket to hold the fuel bladder. This lands the vehicle with the bladder and basket collapsed, reducing its size for the Mars heat shield. The MAV designed as a single stage with oversize fuel bladder so it acts as the TMI stage.
Then lift the Mars Transit Vehicle to ISS with a single Ares V. Include the vehicle with a nuclear thermal engine, and a Nomex umbrella heat shield for aerocapture at Mars. Launch the Mars lander and liquid hydrogen propellant on a second Ares V. Lift the astronauts in Orion, then go.
At Mars the MTV will aerocapture into Mars orbit. The crew lands in the lander, no orbital rendezvous. They of course land at the hab.
After a long stay they as ascend in the MAV. The MAV docks with the MTV and transits back to Earth. The MTV aerocaptures into Earth orbit and spirals (aerobrakes) down to dock with ISS. However, before the MTV aerocaptures the crew depart on Orion for direct entry to Earth.
This leaves the MTV at ISS for the second mission. That starts with a new MAV launch. The first MAV leaves the ISPP factory and power cable rover at the base on Mars so the second one can carry food and supplies. Send it to the first landing site, that is our Mars base.
A single Ares V carries a new lander and LH2 propellant to the MTV. Orion carries the crew, then they go.
This means 4 Ares V launches and 1 Ares I launch for the first mission, 2 Ares V and 1 Ares I launch for each subsequent mission.
Here's the problems:
1. 4 Ares V will only support a 3/4 crew mission (see MD/SEI plans) - six are needed for a robust 3 year expedition.
2. The MTV is just a Hab with engines, it will need refueling and restocking after each mission. The extra mass needed to ensure it's reusable will cost more than it's worth. Better to launch a new, improved one each time.
3. MPD engines require an ENORMOUS amount of power - typically a MW for a 200 N thruster - so a far more powerful reactor would be needed. AFAIK nuclear reactors that work in both gravity and zero gravity don't exist yet.
4. Taking the MTV to ISS (at 51°) is a waste of propellant.
5. LOX/CH4 needs to be stored in low boil off containers. (why not use the MAV tanks?)
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I hope its not going to be generations! I hope to see an era of rapid progress like the early 20th century. Lets just perfect the technology for living on Mars and just go their. Mars is not the place for testing such technology for if it fails people die. Deterimine the reliabilty of the equipment before hand before sending any people. I think if we have until 2031, that is plenty of time to test the equipment, and by that time we should be ready to plant the first colony. We're not going to spend billions of dollars to go to Mars just to see if something works. That is basically my problem with the design reference mission as well, it doesn't use technology which could make it cheaper, it instead wastes billions of dollars going the cautious route until we can be sure we can produce propellent to fuel the return stage. I really don't think we need to be in the vicinity of Mars to test this equipment. I also think the Apollo 10 mission where they almost landed the lunar lander and aborted to see if it works was a waste of money. The might as well have landed the thing and would have had one lunar mission more to justify the expense of Apollo.
I think we should accept some risk. Even a successful colony would have some deaths occuring on Mars. People die on Earth, why shouldn't they also die in space and on Mars. The trick is to see to it that the deaths don't jeapordize the mission, and when missions fail, you just try to fix what is fixable and then you go on. People will die in space and on Mars, if we can't accept that then we shouldn't go there.
Generations of the transportation system, not people. Before Apollo there were two generations in the US system: Gemini and Mercury. After Apollo there was Shuttle and now Constellation. A Mars mission will require additional spacecraft (MTV, lander) and maybe a new inspace propulsion rocket (NTR). It seems unlikely that Mars colonists will be traveling in this generation of equipment.
2031 is a provisional, reference date for a Mars expedition, not a technical one. With enough funding it can be much sooner. If there's a better, cheaper technology fine, but so far there's no contenders. Going to the Moon is still at the edge of current technology, it will expensive and risky. There's more than enough risk already. Currently every crew that launch into space has about a 2% risk of dying. Ares I will reduce that risk by a factor of ten, but a lunar mission will still have about 5% risk, isn't that more than enough? Going to Mars will be more so.
cIclops there are times when I wonder if you are ever able to criticize NASA at all ? I'm not saying you're a Lackey but you hand out a heck of a lot of praise for an agency which got itself stuck in LEO since Apollo. NASA has made great leaps and bounds in un-manned flight like the Voyagers, the MERs on the red Planet, but when it comes to Manned flight the agency has been going backwards since putting American folk on the Moon. You claim Ares-I aka 'The Stick' will increase safety by a factor of Ten. Do you know this for sure or are you just parroting one of those Cheer leading slogans ? You don't need to look for foreign critics when dealing with the issues with The-Stick. Even many Americans are unhappy with these new rocket lines of Stick, former astronauts have criticized it and some people compared it to a giant German hand grenade. I have not seen a good design yet for NASA's manned reusable Mars lander propelled by a NTR . The pics and stats for landing spacecraft and orbiters are varying by many metric tons every time I see a new print to the media by NASA, some of the habitation modules seem to be based more on science fiction than science fact, astronauts may at least need something like a 300 kW nuclear power module but on one of their sites I saw them talking about stuff like Artifical Gravity and Anti-Matter !?!? . Going to Mars will be no joke, it will be putting brave astronauts at risks and one of the things NASA does not deal with properly is the critical issue of a Mars ascent vehicle and the fundamentals of MAV and the ERV systems. It's true that the Soyuz lost people in the first five years of the program but there has been zero of life since despite eight in-orbit emergency. It is a rocket that has been mocked and ignored the West, yet it has a wonderful record, and helped the manned space supremacy for the Russians and even kept the US space program alive after the Shuttle disaster (Ares-I is going to be based on Shuttle components). NASA could have also went the EELV route, a rocket like LM's Atlas-5 lifts a payload comparable to Stick and the Atlas rockets have had success rate of 100% Boeing also had been working on a Delta Heavy Lift.
By the way, your 2031 date is way off the latest from Griffin says America will land people on Mars in 2037
That's 30 years off and with that kind of timetable it looks like Mars is further away than it ever was.
'first steps are not for cheap, think about it...
did China build a great Wall in a day ?' ( Y L R newmars forum member )
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cIclops there are times when I wonder if you are ever able to criticize NASA at all ? I'm not saying you're a Lackey but you hand out a heck of a lot of praise for an agency which got itself stuck in LEO since Apollo. NASA has made great leaps and bounds in un-manned flight like the Voyagers, the MERs on the red Planet, but when it comes to Manned flight the agency has been going backwards since putting American folk on the Moon. You claim Ares-I aka 'The Stick' will increase safety by a factor of Ten. Do you know this for sure or are you just parroting one of those Cheer leading slogans ? You don't need to look for foreign critics when dealing with the issues with The-Stick. Even many Americans are unhappy with these new rocket lines of Stick, former astronauts have criticized it and some people compared it to a giant German hand grenade. I have not seen a good design yet for NASA's manned reusable Mars lander propelled by a NTR .
Yang please try to argue facts or discuss ideas, not resort to ad hominems.
NASA is the only space agency to ever leave LEO, it has done amazing things, only RKA comes close. Is developing and flying the world's only reusable human launch system and the largest, most complex human spacecraft ever built, going backwards? Which space agency should be praised instead, that poorly disguised arm of the Chinese military and communist party propaganda called CNSA?
NASA claims that Ares I will be ten times safer than Shuttle, not me. Yes, there has been some criticism of it as there is of every NASA project, but what is the evidence that it won't be that much safer? (see the Ares I forum for more details)
For details of an NTR based architecture see DRM 3.0.
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1. 4 Ares V will only support a 3/4 crew mission (see MD/SEI plans) - six are needed for a robust 3 year expedition.
According to Zubrin only 4 crew are needed.
2. The MTV is just a Hab with engines, it will need refuelling and restocking after each mission. The extra mass needed to ensure it's reusable will cost more than it's worth. Better to launch a new, improved one each time.
Nope. A hab has life support (oxygen and water recycling), guidance, toilet and sink, kitchen, exercise equipment, etc. And the MTV would be optimized for zero gravity. That throw away mentality is why the space program is in such poor shape.
3. MPD engines require an ENORMOUS amount of power - typically a MW for a 200 N thruster - so a far more powerful reactor would be needed. AFAIK nuclear reactors that work in both gravity and zero gravity don't exist yet.
I see no problem with operating in both gravity and zero gravity.
4. Taking the MTV to ISS (at 51°) is a waste of propellant.
Earth departure doesn't matter if you're at the equator, an inclined orbit, or even polar. The only difference is getting into orbit. Using ISS gives you a construction shack, maintenance dock, and transfer terminal when a reusable space taxi becomes available.
5. LOX/CH4 needs to be stored in low boil off containers. (why not use the MAV tanks?)
Using the MAV as the TEI stage requires extra large tanks. Propellant for TEI departure will be greater than for Mars landing. Besides, if you put the LOX bladder inside the liquid methane bladder, it will cool the methane. Then you only need one refrigeration pump. Oxygen boils at -182.96°C at one atmosphere pressure, I don't have figures for Mars pressure. Methane boils at -161.6°C. Mars atmosphere is cold, Mars Pathfinder recorded temperatures between -7°C in the afternoon to -78°C at night. It's thin atmosphere transfers heat slowly. If you're still worried about boil-off, surround the outer bladder with an air mattress type of thing with multiple layers of aluminized fluoropolymer film, and inflate with argon gas from Mars atmosphere. Separating argon will make the ISPP factory more energy intensive, but as you pointed out the reactor for MPD requires a hell of a lot of power anyway. The inflatable fuel tank reduces weight and reduces size that must be protected by a heat shield during Mars atmospheric entry.
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Yes, non radioactive hydrogen gas is used as the propellant, however in designs such as NERVA it flows through the reactor core so it transports radioactive particles. This radioactive exhaust would quickly circulate in the atmosphere and spread a long distance.
There are other designs which isolate the H2 gas from the core and that should eliminate this problem. Such an engine still needs a large hot reactor core, it will be very difficult to stop radioactive contamination if it falls to the ground. Better not to ignite it until it's safely in orbit, say 1000 kms up.
Space actually begins at 125 km up. Even the Shuttle doesn't go up to 1,000 km in its typical orbit! I think all it should be required to do is reach an orbit, the point is to increase the payload to the Moon and Mars, if we make chemical rockets do more of the work in space, we forgo some advantages of nuclear rockets. Besides, if we listened to the environmentalists all the time we'd forgo all nuclear power sources. I think the best thing for the environment is getting humans into space, and those environmentalist nuts try to stop us at every turn.
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Zubrin is undoubtably a brilliant engineer, however simply quoting his name is insufficient. For short missions of a few weeks or months, 4 or even 3 crew should be fine. 900 days is too long to manage without risk of an accident or illness, a crew of 4 has far less redundancy than a crew of 6.
Almost all the MTV mass is supplies and fuel, they will need to be replaced. Reusing a vehicle after two aerobrakings and three years of deep space use is far too risky. There's nothing "throw away" about it, it's simply too expensive.
AFAIK nuclear reactors need different cooling system when there is no gravity.
Launching the same payload to ISS at 51° from US sites needs more propellant. The cost of ISS crew time and putting all the necessary equipment and parts on board to refurbish and test the MTV would be enormously expensive. When launch costs are low enough to support a "construciton shack" it will still be cheaper just to launch from the ground. Working on the ground will be cheaper than orbit for a long long time.
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A nuclear rocket wouldn't operate in zero gravity, as it would be accelerating.
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Zubrin is undoubtably a brilliant engineer, however simply quoting his name is insufficient. For short missions of a few weeks or months, 4 or even 3 crew should be fine. 900 days is too long to manage without risk of an accident or illness, a crew of 4 has far less redundancy than a crew of 6.
A crew of 2 scientists and 2 engineers is sufficient. One complaint with astronauts is any medical doctor would be constantly poking them with medical experiments to keep himself busy. Their experience with Mercury/Gemini/Apollo doctors was not positive. I don't even know who the 6th crew member is supposed to be.
Most of the MTV mass is not supplies or fuel. However, did you realize the manufacturing cost of a Soyuz spacecraft is as great as launch cost for the rocket that lifts it? That includes manufacturing of the launch vehicle, fuel, and launch services. Stop dismissing spacecraft manufacturing cost, it is significant.
Nuclear reactors use a different cooling system for the vacuum of space than they do here on Earth. Pressurized coolants operate without gravity, they work by pressure. The thin atmosphere on Mars will have similar cooling issues as space. As for design, stop complaining tell the nuclear engineers to just get to work.
The old ISS inclination issue has been an excuse ever since NASA partnered with the Russian Space Agency. Reality is since the late 1960s NASA intended its space station to orbit at 400km altitude and 50° inclination. The station currently orbits at 396-407km altitude and 51.6° inclination. Russia's participation only increased inclination by 1.6°, that's insignificant. That change was to pass over the Svobodniy cosmodrome. Ironic considering they still use Baikonur at 45.63° latitude.
The cost of ISS crew time and putting all the necessary equipment and parts on board to refurbish and test the MTV would be enormously expensive.
To use a line from a member of another forum, I have to call bullshit. You can't use ISS construction as an example, refuelling and replenishing the MTV would simply be a matter of docking the new propellant thank, and crawling in through the hatch to replenish food in the kitchen. That can be done easily in an hour. Simple and inexpensive. The key is to not design it the way ISS is designed.
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The mass needed for a mission is roughly proportional to crew size. Seems to be one Ares V per crew member
Is a medical specialist not needed for a three year journey involving 500 days of surface exploration in a hostile environment? Engineering and Science are probably the key functions that need to be distributed across the crew. So in theory someone with knowledge of both and a medical kit would be enough
Following the rule of making critical systems redundant, two people then would be the absolute minimum (plus two kits). As these are key areas, it seems logical to have specialists for each one, applying the redundant rule again gives four crew.
In addition medical & command skills are important, as well as the needs for knowledge of the flight systems, life sciences, fossils, geology, chemistry, atmospheric science, propulsion, communications, computers, navigation, rovers, ISRU, nuclear surface power, psychology, group dynamics, cooking etc etc. All that surely requires one more generalist crew member. Add the backup and there's the magic six. Given the enormous cost of such a mission and its duration, ensuring sufficient skills and knowledge are available is essential to its success.
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The mass needed for a mission is roughly proportional to crew size. Seems to be one Ares V per crew member
Is a medical specialist not needed for a three year journey involving 500 days of surface exploration in a hostile environment? Engineering and Science are probably the key functions that need to be distributed across the crew. So in theory someone with knowledge of both and a medical kit would be enough
Following the rule of making critical systems redundant, two people then would be the absolute minimum (plus two kits). As these are key areas, it seems logical to have specialists for each one, applying the redundant rule again gives four crew.
In addition medical & command skills are important, as well as the needs for knowledge of the flight systems, life sciences, fossils, geology, chemistry, atmospheric science, propulsion, communications, computers, navigation, rovers, ISRU, nuclear surface power, psychology, group dynamics, cooking etc etc. All that surely requires one more generalist crew member. Add the backup and there's the magic six. Given the enormous cost of such a mission and its duration, ensuring sufficient skills and knowledge are available is essential to its success.
Let me introduce a new concept here:
There are Launch Rockets and Space Rockets.
Launch Rockets are used to get payloads into Low Earth Orbit, the property of Launch Rockets are that they have high thrust to weight ratios, they need this in order to overcome Earths gravity and air resistance - for example in order to accelerate upwards at 9.8 meters per second squared from Earth's surface, your rocket needs to accelerate at 2g. (1g to overcome Earth's gravity and 1g to accelerate upwards at 9.8 meters per second squared, meglecting air resistance.) Now if you factor in air resistance, then that force increases as you increase your velocity relative to Earth and decreases as you increase your altitude. Now the problem with the Design Reference Mission is that it uses Upper Stage Launch Rockets to get to Mars, the problem is that this is hugely wasteful of material propellent, and payload to Low Earth orbit. Much of that chemical propellent lifted into Low Earth Orbit could otherwise go mission critical payloads to Mars orbit and surface as well as provisions and supplies for extra crew members. For a mission planned for 2031, using a Launch Rocket to go from Low Earth Orbit to Low Mars Orbit is just plain stupid, and we are stupid if we fail to develop the appropriate Space Rocket that will most efficiently deliver our Mars Payload from Low Earth Orbit to Low Mars Orbit.
There are several kinds of space propulsion rockets that could conceivably be employed, there is the Plasma Rocket, the Fusion Rocket, the Ion Rocket, and the Nuclear Fission Rocket. Of those four, we so far have Nuclear Fission Rockets and Ion Rockets. I believe there were some experiments with plasma rockets, and a fusion rocket of some sort may be possible, reaching the ignition point for fusion isn't a strict requirement, the extra energy that fusion brings to add to the plasma will increase the efficiency of the propulsion by that much. The main problem with Space Rockets are that they have low thrust to weight ratios, but they make up for this by being very efficient in the amount of propellent they consume to achieve their total change in velocity. Such propulsion systems are "energy hogs", and thus require at least a nuclear reactor to generate the high amounts of energy required. Building a Space Rocket is a project in itself, but if we are going to wait to 2031, we have the time to build one. So don't tell me that after 24 years we still are going to use 6 Ares V Rockets with their upper stage Launch rockets to get to Mars. Such a high price per mission is going to make the whole project attractive to budget balancers and cost cutters for elimination. Also such a high price for interplanetary travel leaves space travel in the province of governments, and what we really need to do if we are going to live in the 21st century for real is to bring those costs down. We want to enable private companies and rich individuals or individuals with rich sponsors to be able to get to Mars and other locations and eventually all of us.
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Planning for the Scientific Exploration of Mars by Humans (doc 7MB) - February 2008
The Human Exploration of Mars Scientific Analysis Group (HEM-SAG) derived human science reference missions using constraints provided by engineers affiliated with the 2007 Mars Architecture Team (B. Drake et al., NASA JSC) (edit: this is the unreleased DRM 5.0)
For the first three human missions: three different sites or the same site?
Three independent sites.For the first three human missions should they be: “short stay (~30 days)” or “long Stay (~500 days)”?
Three long-stay (~500 days) missions to maximize scientific return.How much surface mobility, in terms of radial distance from landing site, would be required to perform the required science?
Human mobility (horizontal)/pressurized human rover >200 km radial (Perhaps >500 km).What would be the subsurface access requirements?
Vertical subsurface access (drilling) ~300 m at one site for access to subsurface liquid water zones, if available; less (5-50 m) at multiple sites on traverses. Selective recoverable coring, e.g., polar climate coring to depth of 300 m.How would we implement a search for extant life vs. a search for fossil life? (Assessing the human of human explorers on the search for extant life)
Very carefully. The search for extant biology must be an important scientific goal/objective of human exploration. Humans have a great deal of experience in carrying out aseptic sampling of exteme environments on Earth to carry forward in this endeavor
Human in-situ analyses on Mars vs. returning samples to Earth for analyses (Mass of instrumentation/equipment transported from Earth to Mars for in situ analyses on Mars versus amount of sample mass to be returned to Earth)
Human habitat/work station: In situ sample analysis and cataloging: Analyses that could not be performed on Earth, e.g., tests for extant life.
Samples would include rocks, drill cores, surface/atmospheric dust, ice, atmospheric gas.
Sample conditioning and preservation would be essential.
Human habitat LAB instruments for multiple objectives: Geology, Atmosphere/Climate and Biology/Life.
Emplacement of network stations for Geophysics, Atmosphere/Climate and even Biology/Life would be essential beyond initial landing site (200-400 km radial from landing site) to be operated during and after humans return to Earth.How much sample mass should be returned to Earth?
Mass of samples returned to Earth >250 kg.
See also:
Geophysics: Human Exploration Goals and Objectives (doc 8MB) - February 2008
Therefore, when humans explore Mars, it would be prudent to follow our experience in the first great wave of the human exploration of other planetary bodies, the Apollo Lunar Exploration Program. We should plan for a program, not a single landing. We should build in broad capabilities from the start, to take advantage of what we learn at each step along the way. We should understand that the true lasting legacy is not just going to Mars, but what can actually be accomplished by humans when they are there, and the scientific results that they can obtain. Using these simple guidelines as a broad compass will lead us to a successful human exploration of Mars, and a legacy that will outlast us all.
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For the first three human missions: three different sites or the same site?
Three independent sites.
Oh (*&#(*&#(%*!!!!!!!!!
There was a question of whether to conduct exploration of multiple independant sites with human explorers, or whether to explore with unmanned probes then build a base at a single location with human explorers. That question has already been answered: exploration with unmanned probes has already been done. That means NASA has committed itself, it is now constrained to build a base at one single location. After president George H. W. Bush gave his speach in 1989, then NASA's 90-day report, Robert Zubrin and David Baker produced the Mars Direct plan in 1990. If we followed it we would have had humans on Mars by 1999.
An ideal launch window was Mars close approach, 2003. There won't be another close approach until 2287. There are perihelic oppositions of Mars every 15 to 17 years, but they won't be as close. We should be planning the first mission for 2018 to 2020, not 2031.
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When and where did NASA commit to building a single Mars base? DRM 5.0 has no basing concepts defined, only a Habitation module for each mission. Just because the MEPAG scientists want three independent sites visited doesn't mean that a central base can't be constructed. These scientific sites can be visited with sortie missions (as in lunar exploration) or by long distance rovers or hoppers. There's 58 sites listed, so there may be three or more clustered within range of a single base that would be equivalent.
2018 would be great, got a few hundred billion dollars to spare?
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No, a few hundered billion dollars would be used on the 90 day plan. 8)
Use what is abundant and build to last
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Yea, well, NASA appears to be proceeding with the 90-day report whether we like it or not. That report was before ISS was built. It called for a space station, orbital fuel depot, permanent lunar base with mines to extract oxygen from lunar regolith, tankers to bring oxygen back to Earth orbit, and a giant nuclear power spacecraft to go to Mars and back. It would take 26 months round trip but only half the crew would descend to the surface, and they would only spend 2 to 4 weeks on the surface. Well, nuclear power would be a good thing, but not a giant spaceship, not only half the crew down, and not a short stay. NASA has seen the light somewhat, they now talk about everyone on the surface and long stay. However, ISS is nearly complete, work on expendable rockets and a spacecraft that can only be called Apollo on steroids, and plans for a permanent lunar base. I saw a piece on the Discovery Channel of a lunar truck that is nearing completion, that will do construction work for the lunar base. Now DRM 5 calls for expendable habitats for each mission. We're getting the 90-day report in pieces.
Hey, GCNRevenger, you wanted the Gas Core Nuclear Rocket, hence your name. George W. Bush is a strong advocate for nuclear power, but has less than a year left to his mandate. How about lobbying NASA and more importantly Dubya's staff to develop a nuclear TMI stage. Either gas core or solid core. It would be really, really good, and time is running out.
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The new VSE Lunar plan won't be Apollo 2.0, because it can't be... the damage to NASA's credibility might well be fatal. And, while the crew and cargo vehicles might resemble Apollo's, they will have far more capability with Orion's 6mo orbital loiter, Altair's ~20MT cargo payload, and so on.
As far as expendable habitats, whats wrong with that? All the Mars plans call for expendable HABs, just some of them call for the HABs to be clustered at a single site and then get labeled a "base." It is entirely reasonable to discuss the scientific payoffs of global manned exploration with fully expendable sortie missions earlier rather than waiting for a central base to have access to the same sites much later.
Build a nuclear engine now? Actually, I am opposed to that, at least for the moment. A solid-core NTR engine would be nice, but the benefits are marginal compared to the costs. A GCNR engine would be swell, but that would break the bank for NASA I'm afraid, best to hold off on that sort of thing for now.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
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If we don't build bases on Mars, the costs of exploring it will remain high, and we'll never be able to go anywhere else.
"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane
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Oh I agree, Commodore, in the long run anyway...
...But in the short term, while the details and equipment for a Mars base are build developed (heavier reactor, ISRU plant, reuseable lander/hopper) we shouldn't stop sending missions. And if we aren't quite ready for a base yet, then they could be global sortie missions.
It would also help keep up the publics' interest.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Thre is no long run, short run stuff. If you explore Mars with expendable equipment, there will never be a permanent base, there will never be exploration anywhere else in the solar system, and Mars exploration itself will be short lived: flags and footprints. Built a permanent base with the first ever human mission to Mars, or forget human exploration all together.
As for cost, let me quote you some figures. The Russian Energia launch vehicle was available at a cost of $120 million per launch plus the cost to restore infrastructure. That includes the Energia upper stage, and is a hard price quoted to NASA, but it was in March 1994 dollars. I estimated an updated price, for 2008 it would be $160 million to restore infastructure, and $170 million per launch. These prices are in millions, with an 'M". NASA is now spending how much for development of Ares V? What will the per launch cost be?
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Thre is no long run, short run stuff. If you explore Mars with expendable equipment, there will never be a permanent base, there will never be exploration anywhere else in the solar system, and Mars exploration itself will be short lived: flags and footprints. Built a permanent base with the first ever human mission to Mars, or forget human exploration all together.
As for cost, let me quote you some figures. The Russian Energia launch vehicle was available at a cost of $120 million per launch plus the cost to restore infrastructure.
Of course there is a short and long run, even if the long run is the second phase of Mars exploration. That's already happened many times, with the early global voyages of the Portuguese followed by Spanish colonization. Antarctic exploration followed the same pattern. A similar split will happen with the exploration of the Moon. Why should Mars be any different? We learn from the inefficiencies of the past and have better technology, so the process ought to happen faster. But Mars is a BIG step not only in distance but also in cost and technology. There will probably be three or more phases: initial sorties, outpost / base then colony.
Forget Energia, it will never fly a third time. It would cost more than $120m (even in PPP rubles) to develop a modern flight control system for it, let alone restoring the entire program. It's old technology and its launch capacity is too small.
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
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Thre is no long run, short run stuff. If you explore Mars with expendable equipment, there will never be a permanent base, there will never be exploration anywhere else in the solar system, and Mars exploration itself will be short lived: flags and footprints. Built a permanent base with the first ever human mission to Mars, or forget human exploration all together.
As for cost, let me quote you some figures. The Russian Energia launch vehicle was available at a cost of $120 million per launch plus the cost to restore infrastructure. That includes the Energia upper stage, and is a hard price quoted to NASA, but it was in March 1994 dollars. I estimated an updated price, for 2008 it would be $160 million to restore infastructure, and $170 million per launch. These prices are in millions, with an 'M". NASA is now spending how much for development of Ares V? What will the per launch cost be?
Um, but isn't MarsDirect that you subscribe to all expendable and bad and stuff, Robert? There is no provision for reuseability at all in Zubrin's plan.
It will take much longer for NASA to be ready to build a base and required equipment that supports global/near-global access to Martian sites of interest, and we will have already developed everything we need for a sortie-type expendable mission. So why wait? The first several missions would fly while NASA develops the stuff we need for a base, particularly since the R&D money would be freed up from the basic Mars architecture. It would probably help to confirm, with a manned landing, where we want to put our base anyway, right?
And come on, Energia? Thats just "Red-worshiping" and/or "gaetanomorono-grade" anti-NASA nonsense, the Russians are just trying to save face. Energia is dead.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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If you don't like Energia just because it's Russian, then you come up with a way to dramatically slash costs. Remember NASA currently pays at least 10 times what any task is worth. After Columbia the cost of the Shuttle jumped 50%, and I'm not convinced any of the work was worth any increase in cost. Removing a ramp of foam, putting some cameras on the shuttle; come on, that's just operations. The tile repair kits and inspection boom were good, but once built they're built; no excuse for on-going increased costs. And those things should have been built right at the beginning. In fact NASA had flown a small ball inspection camera, the boom is primarily for repairs. Since the had the boom to hold astronaut feet while conducting repairs, they might as well put a camera on it for inspection as well. But the increase in annual cost was just price gouging by contractors. We're never going to get anywhere as long as this price gouging continues. I've come to the conclusion that American major space contractors (all of whom are military contractors) consider NASA to be a make-work project, they don't value NASA objectives at all. So it's time to find alternatives. SpaceX is making a good try within the US, but Energia is the only existing HLLV that can be resurrected. If you don't like either of those, how are you going to cut costs to 10% while at the same time increasing quality and reliability, and increasing launch rate?
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Energia was also the product of Soviet defense contractors, only theirs performed under the threat of a one way trip to Siberia.
American defense contractors answer to stockholders, millions of Americans of all walks of life who all depend on maximum profit to fund retirement, college, ect.
"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane
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We're never going to get anywhere as long as this price gouging continues. I've come to the conclusion that American major space contractors (all of whom are military contractors) consider NASA to be a make-work project, they don't value NASA objectives at all. So it's time to find alternatives. SpaceX is making a good try within the US, but Energia is the only existing HLLV that can be resurrected. If you don't like either of those, how are you going to cut costs to 10% while at the same time increasing quality and reliability, and increasing launch rate?
I don't like Energia primarily because I don't think we can trust the Russians, whether the rocket could be successfully resurrected or not. And just how far gone does a rocket need to be before you consider it beyond "resurrecting?"
And Shuttle's cost jumped 50%? That would probably be due to the lower flight rate for a system that is virtually all fixed costs and the increase in detailed inspection & maintenance to eek out the last little bit of reliability they can in The Worlds Most Complex Machine during its twilight years so that a third Shuttle disaster doesn't deep-six NASA.
About the contractor gouging, its really a self-regulating system, give or take: the big aerospace contractors can charge a high price, but they can't ask for more than NASA has to give, otherwise the contractor doesn't get any money. Yes the big contractors have basically a monopoly on manned flight hardware, but likewise NASA is the only customer for their expensive wares.
It goes both ways... ultimately it yields a tight budget for NASA, but not beyond affordability.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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