Use commercial to get to moon

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DarkenedOne

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NASA's architecture for getting back to the moon involved 3 different space craft, the crew capsule, the EDS, and the lunar lander.

SpaceX's crew capsule seems to be a smaller version of Orion. With a few modifications it could serve as a downsized version of Orion. That leaves only two elements left for a moon mission would be an Earth Departure Stage and a Lunar Lander.

SpaceX's crew capsule is smaller than Orion, so it will probably be able to deliver 2-3 people, but that seems good to me at least for a moon base.

Choosing this path has great benefits over the Constellation Program in that both cost and risk would be greatly reduced. The only remaining question is whether or not SpaceX crew capsule will pan out. Only time will tell.
 
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Crossover_Maniac

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In the next two or three years, the VASIMR rocket will be tested on the space station. There's no reason why a heavy lifter could be used to ferry astronauts from LEO to LLO.
 
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rockett

Guest
DarkenedOne":3slnyx95 said:
NASA's architecture for getting back to the moon involved 3 different space craft, the crew capsule, the EDS, and the lunar lander.

SpaceX's crew capsule seems to be a smaller version of Orion. With a few modifications it could serve as a downsized version of Orion. That leaves only two elements left for a moon mission would be an Earth Departure Stage and a Lunar Lander.

SpaceX's crew capsule is smaller than Orion, so it will probably be able to deliver 2-3 people, but that seems good to me at least for a moon base.

Choosing this path has great benefits over the Constellation Program in that both cost and risk would be greatly reduced. The only remaining question is whether or not SpaceX crew capsule will pan out. Only time will tell.
Wonderful idea, but I have a few questions:
1. LEO only requires a minimum amout of radiation shielding because the capsule is still within the Earth's magnetosphere. How are you going to handle additional radiation exposure?
2. I thought the Dragon could carry up to 7 people. Why only 3-4? http://www.spacex.com/dragon.php
3. Are you thinking direct landing on Earth afterward or in-orbit rendezvous? If direct landing the Dragon would require a MUCH heavier heat shield. Return from LEO is usually around 7.6 km/sec, but lunar return is 10-11 km/sec if I recall correctly. If you rendezvous in orbit, it will require more fuel.
 
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rockett

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Crossover_Maniac":1bfl9j00 said:
In the next two or three years, the VASIMR rocket will be tested on the space station. There's no reason why a heavy lifter could be used to ferry astronauts from LEO to LLO.
True VASIMR will be tested on the ISS, but according to Bolden, we won't see heavy lifter until 2020 to 2030. Maybe I don't quite understand what you are saying. What does that have to do with VASIMR?
 
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edkyle99

Guest
DarkenedOne":2d22x07g said:
NASA's architecture for getting back to the moon involved 3 different space craft, the crew capsule, the EDS, and the lunar lander.

SpaceX's crew capsule seems to be a smaller version of Orion. With a few modifications it could serve as a downsized version of Orion. That leaves only two elements left for a moon mission would be an Earth Departure Stage and a Lunar Lander.

SpaceX's crew capsule is smaller than Orion, so it will probably be able to deliver 2-3 people, but that seems good to me at least for a moon base.
SpaceX is not building a crew capsule, at least not yet. It is building a cargo transfer capsule that could, conceivably, be developed into a crew capsule if someone provides the funding. In addition, Dragon is a short-hop LEO spacecraft, not a deep-space machine. A lot more money would be needed to develop it into the latter machine. Note, for example, that the COTS Dragon is not docking to ISS, but is being berthed by a robot arm. There are no robot arms in deep space! Dragon's heat shield would have to be beefed up for lunar return, etc.

I'm not saying it is impossible, just that it would take more time and money than most realize.

As for using commercial to create a lunar mission, there are ways to do it I think. Personally, I'm liking a concept that involves use of hypergolic storable propellant for all beyond-LEO propulsion, including the trans-lunar injection stage. A storable TLI stage could be orbited and gradually filled with 90-100 tonnes of propellant by commercial launch service companies to achieve an Apollo-class capability. Because it would be storable, the TLI stage could orbit for many months, years even, while being filled, without worrying about propellant boil-off. This could allow a slow mission rate that could be tailored to available funding. Instead of two missions per year, NASA could think about one mission every two years, or thereabouts (though the depot-filling launches would occur steadily, every few months or so). No new launch vehicles or launch infrastructure would be required! This architecture wouldn't support a lunar base unless lots more funding appeared out of the Congressional ether, but there are plenty of sortie exploration missions that could be performed for many years. Humans have only stopped at six sites on the Moon after all.

- Ed Kyle
 
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DarkenedOne

Guest
edkyle99":110plxh5 said:
SpaceX is not building a crew capsule, at least not yet. It is building a cargo transfer capsule that could, conceivably, be developed into a crew capsule if someone provides the funding. In addition, Dragon is a short-hop LEO spacecraft, not a deep-space machine. A lot more money would be needed to develop it into the latter machine. Note, for example, that the COTS Dragon is not docking to ISS, but is being berthed by a robot arm. There are no robot arms in deep space! Dragon's heat shield would have to be beefed up for lunar return, etc.
SpaceX has stated from the beginning that their eventual goal was to be in the human spaceflight business. The Falcon 9 was designed from the beginning to fulfill all of the requirements for a manned mission. The dragon was also designed from the beginning to ferry both people and cargo complete with a heat shield and reentry capability. SpaceX has stated that they will develop the dragon crewed version after they finish developing the dragon cargo version.

It is also true that the Dragon was not designed for deep space missions. however the Moon is generally not considered deep space as it is only 5 days away. The Dragon definitely has the endurance for a back and forth trip.

Your right about the heat shield and docking, but I believe that they can make the necessary modifications.


edkyle99":110plxh5 said:
I'm not saying it is impossible, just that it would take more time and money than most realize.

As for using commercial to create a lunar mission, there are ways to do it I think. Personally, I'm liking a concept that involves use of hypergolic storable propellant for all beyond-LEO propulsion, including the trans-lunar injection stage. A storable TLI stage could be orbited and gradually filled with 90-100 tonnes of propellant by commercial launch service companies to achieve an Apollo-class capability. Because it would be storable, the TLI stage could orbit for many months, years even, while being filled, without worrying about propellant boil-off. This could allow a slow mission rate that could be tailored to available funding. Instead of two missions per year, NASA could think about one mission every two years, or thereabouts (though the depot-filling launches would occur steadily, every few months or so). No new launch vehicles or launch infrastructure would be required! This architecture wouldn't support a lunar base unless lots more funding appeared out of the Congressional ether, but there are plenty of sortie exploration missions that could be performed for many years. Humans have only stopped at six sites on the Moon after all.

- Ed Kyle
While storing fuel in space is a intermediate ability that needs to be developed especially for deep space missions, I do not believe it is necessary for going to the moon.

With an earth departure stage current vehicles are easily able to make it to the moon. Space Adventures is offering to fly people around the moon and back for $100 million per person. They intend to do it the same way NASA wanted to with Constellation except at a much smaller scale and without the lunar lander. The Soyuz only weighs about 5000kg meaning it will only take about a 10000to 15000kg Earth Departure Stage to take it to the moon. The EDS would be launched separately on an existing heavy lift rocket, dock with the Soyuz, and then take it into lunar orbit and back.

Of course I am sure that NASA will not take up the offer because it relies on the Soyuz, but the same concept would work well for the Dragon at a comparable cost.
 
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DarkenedOne

Guest
rockett":2tp3571z said:
Wonderful idea, but I have a few questions:
1. LEO only requires a minimum amout of radiation shielding because the capsule is still within the Earth's magnetosphere. How are you going to handle additional radiation exposure?
True, however this was not so much a problem for Apollo because they passed through it pretty quickly.

rockett":2tp3571z said:
2. I thought the Dragon could carry up to 7 people. Why only 3-4? http://www.spacex.com/dragon.php
I do not know the exact number. The Dragon can carry 7 people to and from the station. In order to get to the moon you would need significantly more endurance.

rockett":2tp3571z said:
3. Are you thinking direct landing on Earth afterward or in-orbit rendezvous? If direct landing the Dragon would require a MUCH heavier heat shield. Return from LEO is usually around 7.6 km/sec, but lunar return is 10-11 km/sec if I recall correctly. If you rendezvous in orbit, it will require more fuel.
I believe that it would not be that difficult to beef up the heat shield.
 
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neutrino78x

Guest
Could an Earth Departure Module that you attach to the Dragon in LEO also land the Dragon on the Moon?

Can we do ISRU to generate fuel for the return trip on the Moon?

--Brian
 
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Crossover_Maniac

Guest
rockett":edonsb59 said:
Crossover_Maniac":edonsb59 said:
In the next two or three years, the VASIMR rocket will be tested on the space station. There's no reason why a heavy lifter could be used to ferry astronauts from LEO to LLO.
True VASIMR will be tested on the ISS, but according to Bolden, we won't see heavy lifter until 2020 to 2030. Maybe I don't quite understand what you are saying. What does that have to do with VASIMR?
Heavy lift is a bit of an ill defined term. I was referring to a Delta-IV Heavy or Atlas V unless the Falcon-9 Heavy is successful.
 
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pathfinder_01

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Crossover_Maniac":1c31uiy6 said:
In the next two or three years, the VASIMR rocket will be tested on the space station. There's no reason why a heavy lifter could be used to ferry astronauts from LEO to LLO.
Vasimr will not replace chemical boosters for moving people to the moon. They are a great way to move cargo, but depending on how much cargo you have and how much power, it will take weeks to get to the moon. I think the claim is 3 weeks for a lunar tug. That is too long for people esp. during the trip through the van allen belt. Vasimir could be a good way to move people to mars or places futher out.

The current rockets you mentioned would probably be unable to send a capsule with people to the moon and put them in LLO. However you could divide the payload in such a way that they could(might take 3-6 launches or more) or build propelent depots or use electric propulsion to move everything but the capsule.

A heavy lifter IMHO would be nice but something smaller than a Saturn V. Something able to put 60-80 tons into LEO. That could be enough to enable a manned moon mission in two launches. Or put up a small space plane(or other item) to increase ISS downmass. Or launch something big to the ISS. I think there is a role for comercial, so if a payload can be lifed by a commerical booster then it should, but I think the government could handle moving large pieces of payload until a market appears.
 
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Crossover_Maniac

Guest
pathfinder_01":1h5p4pfp said:
Crossover_Maniac":1h5p4pfp said:
In the next two or three years, the VASIMR rocket will be tested on the space station. There's no reason why a heavy lifter could be used to ferry astronauts from LEO to LLO.
Vasimr will not replace chemical boosters for moving people to the moon. They are a great way to move cargo, but depending on how much cargo you have and how much power, it will take weeks to get to the moon. I think the claim is 3 weeks for a lunar tug. That is too long for people esp. during the trip through the van allen belt. Vasimir could be a good way to move people to mars or places futher out.
Ships designed trips outside of LEO would have to have more radiation shielding for solar flares anyway. Whatever will protect a ship from a flare will protect it from the Van Allen Belt. The trip time can be diminished by using thin-film solar panels to power VASIMR. The amount of power per weight ratio are six time lighter than current solar panels or nuclear systems. Added power means a higher amount of thrust and a decrease in trip time.
 
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pathfinder_01

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Crossover_Maniac":hrp1yvud said:
pathfinder_01":hrp1yvud said:
Crossover_Maniac":hrp1yvud said:
In the next two or three years, the VASIMR rocket will be tested on the space station. There's no reason why a heavy lifter could be used to ferry astronauts from LEO to LLO.
Vasimr will not replace chemical boosters for moving people to the moon. They are a great way to move cargo, but depending on how much cargo you have and how much power, it will take weeks to get to the moon. I think the claim is 3 weeks for a lunar tug. That is too long for people esp. during the trip through the van allen belt. Vasimir could be a good way to move people to mars or places futher out.
Ships designed trips outside of LEO would have to have more radiation shielding for solar flares anyway. Whatever will protect a ship from a flare will protect it from the Van Allen Belt. The trip time can be diminished by using thin-film solar panels to power VASIMR. The amount of power per weight ratio are six time lighter than current solar panels or nuclear systems. Added power means a higher amount of thrust and a decrease in trip time.
The trouble here is that a chemical rocket has way more thrust than any electrical propulsion system. Electric propulsion has more isp. Given enough time an electrically powered rocket can be faster than a chemical one. The trouble is it is only a few days to the moon for a chemical rocket while it is weeks to the moon for a electric one. The moon just is too close for electrical propulsion to gain a speed advantage. Other advantages is not needing to carry weeks worth of supplies and\ or recycling systems. Plasma is great for cargo to the moon, not people.

Electric rockets are low thrust\high isp. This is why a chemical rocket can beat it to the moon, but on a longer trip to mars the electric one can equal or even beat the chemical. It is sort of like a corvette and a hybrid in a race. The corvette could out accelerate the hybrid, but the hybrid car would be able to cover more distance with equal fuel.

An chemical rocket generates all the power needed to get to the moon in say ten minutes. An electrical rocket works constantly slowly accelerating the decelerating the craft to it's destination. Given enough time it could accelerate to a speed much faster than a chemical one. It is just that on a trip to the moon there is not enough time. The only real advantage vasmir would have on the trip is it would use less propellant. Nice for cargo that doesn't need life support. Not nice for people.

As for the danger of radation, three things go into how dangerous radiation is. The type, amount, and how long you are exposed. The less time you are exposed the better. Lowing the amount is helpful, but lowering the time is far more.
 
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DarkenedOne

Guest
pathfinder_01":1tgftq0w said:
Vasimr will not replace chemical boosters for moving people to the moon. They are a great way to move cargo, but depending on how much cargo you have and how much power, it will take weeks to get to the moon. I think the claim is 3 weeks for a lunar tug. That is too long for people esp. during the trip through the van allen belt. Vasimir could be a good way to move people to mars or places futher out.

The current rockets you mentioned would probably be unable to send a capsule with people to the moon and put them in LLO. However you could divide the payload in such a way that they could(might take 3-6 launches or more) or build propelent depots or use electric propulsion to move everything but the capsule.

A heavy lifter IMHO would be nice but something smaller than a Saturn V. Something able to put 60-80 tons into LEO. That could be enough to enable a manned moon mission in two launches. Or put up a small space plane(or other item) to increase ISS downmass. Or launch something big to the ISS. I think there is a role for comercial, so if a payload can be lifed by a commerical booster then it should, but I think the government could handle moving large pieces of payload until a market appears.
Current chemical rockets are able to get a small human spacecraft to the lunar orbit. The Soyuz for example weights about 5000kg. It can be launched into lunar orbit if it docks with a earth departure stage like NASA was planning on doing with Constellation. A 15000kg Earth Departure Stage could easily put the Soyuz into lunar orbit. In fact Space Adventures is offering to do that for a moon trip.

The problem is the lunar module which weighs much more. The Apollo lunar module is probably as small as you want to get and it weighed 15000 kg.

In the interest of cost it would probably be best to develop a reusable lunar tug to ferry cargo and habitats as well as the lunar module to the moon. It would use high isp, low thrust electric propulsion. Of course it would take over a month to get there but that is ok.

Once everything is in place a capsule such as the Soyuz or SpaceX can take off, dock with a Earth Departure Stage, rocket into lunar orbit, dock with a lunar module that was waiting for it, then proceed to the lunar surface.
 
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edkyle99

Guest
DarkenedOne":7hlw0z1z said:
While storing fuel in space is a intermediate ability that needs to be developed especially for deep space missions, I do not believe it is necessary for going to the moon.

With an earth departure stage current vehicles are easily able to make it to the moon. Space Adventures is offering to fly people around the moon and back for $100 million per person. They intend to do it the same way NASA wanted to with Constellation except at a much smaller scale and without the lunar lander. The Soyuz only weighs about 5000kg meaning it will only take about a 10000to 15000kg Earth Departure Stage to take it to the moon. The EDS would be launched separately on an existing heavy lift rocket, dock with the Soyuz, and then take it into lunar orbit and back.

Of course I am sure that NASA will not take up the offer because it relies on the Soyuz, but the same concept would work well for the Dragon at a comparable cost.
The CCCP tried, but never fully developed, this concept (unmanned tests flown as Zond capsules boosted by Blok D stages). I wonder why Russia hasn't tried it again, since Proton has grown up sufficiently to provide more orbital mass. I also wonder if China isn't working up to this type mission.

It is a neat stunt, one that might garner interest among Earthlings too young to remember Apollo, but no one would pay attention to the second mission, or the third, and so on.

People need to land, on the Moon. More than one geologist needs to walk there, dig there in more than one place. Someone needs to go see the frozen water and sift it through their gloved fingers.

- Ed Kyle
 
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pathfinder_01

Guest
edkyle99":341mizq8 said:
DarkenedOne":341mizq8 said:
While storing fuel in space is a intermediate ability that needs to be developed especially for deep space missions, I do not believe it is necessary for going to the moon.

With an earth departure stage current vehicles are easily able to make it to the moon. Space Adventures is offering to fly people around the moon and back for $100 million per person. They intend to do it the same way NASA wanted to with Constellation except at a much smaller scale and without the lunar lander. The Soyuz only weighs about 5000kg meaning it will only take about a 10000to 15000kg Earth Departure Stage to take it to the moon. The EDS would be launched separately on an existing heavy lift rocket, dock with the Soyuz, and then take it into lunar orbit and back.

Of course I am sure that NASA will not take up the offer because it relies on the Soyuz, but the same concept would work well for the Dragon at a comparable cost.
The CCCP tried, but never fully developed, this concept (unmanned tests flown as Zond capsules boosted by Blok D stages). I wonder why Russia hasn't tried it again, since Proton has grown up sufficiently to provide more orbital mass. I also wonder if China isn't working up to this type mission.

It is a neat stunt, one that might garner interest among Earthlings too young to remember Apollo, but no one would pay attention to the second mission, or the third, and so on.

People need to land, on the Moon. More than one geologist needs to walk there, dig there in more than one place. Someone needs to go see the frozen water and sift it through their gloved fingers.

- Ed Kyle
Zond at best was partially sucessful. Soyuz lacked the lift to drag ratio of apollo and could not renenter from the moon directly. They would have needed a tricky skip on the atmophere kind of thing. Possible, just not so straightfoward and perhaps a bit more risky.
 
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Crossover_Maniac

Guest
pathfinder_01":1n2zlic9 said:
The trouble here is that a chemical rocket has way more thrust than any electrical propulsion system. Electric propulsion has more isp. Given enough time an electrically powered rocket can be faster than a chemical one. The trouble is it is only a few days to the moon for a chemical rocket while it is weeks to the moon for a electric one. The moon just is too close for electrical propulsion to gain a speed advantage. Other advantages is not needing to carry weeks worth of supplies and\ or recycling systems. Plasma is great for cargo to the moon, not people.

Electric rockets are low thrust\high isp. This is why a chemical rocket can beat it to the moon, but on a longer trip to mars the electric one can equal or even beat the chemical. It is sort of like a corvette and a hybrid in a race. The corvette could out accelerate the hybrid, but the hybrid car would be able to cover more distance with equal fuel.

An chemical rocket generates all the power needed to get to the moon in say ten minutes. An electrical rocket works constantly slowly accelerating the decelerating the craft to it's destination. Given enough time it could accelerate to a speed much faster than a chemical one. It is just that on a trip to the moon there is not enough time. The only real advantage vasmir would have on the trip is it would use less propellant. Nice for cargo that doesn't need life support. Not nice for people.

As for the danger of radation, three things go into how dangerous radiation is. The type, amount, and how long you are exposed. The less time you are exposed the better. Lowing the amount is helpful, but lowering the time is far more.
Ad Astra actually published a study in which it would take 180 days to get from LEO to LLO using current solar electric propulsion. For the same mass, six times the power could be generated by thin-film meaning six times the thrust and acceleration. This reduces that trip time from 180 days to 20 days. Trip time from LEO to LLO for Apollo was around three days. That's not that much of a difference, not with some of the recent advances in radiation shielding technology.
 
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pathfinder_01

Guest
Crossover_Maniac":2lq7pbqn said:
Ad Astra actually published a study in which it would take 180 days to get from LEO to LLO using current solar electric propulsion. For the same mass, six times the power could be generated by thin-film meaning six times the thrust and acceleration. This reduces that trip time from 180 days to 20 days. Trip time from LEO to LLO for Apollo was around three days. That's not that much of a difference, not with some of the recent advances in radiation shielding technology.
The thing is the thrust of an electric rocket is determined by the amount of propellant expelled in a given time. You will either need an engine capable of handling six times more power, or six smaller ones to do it, or some combination of more engines. Either way odds are the mass of your craft has just increased which will slow it down a bit.

The other thing is the trip is a little more than 6 times longer than a chemical rocket. You now need 6 times the amount of food, water, oxygen, CO2 scrubing canisters ect. Or you will need to add water and reusable CO2 removal which take power, space, and equipment.

Using the ISS as an example a 6 day round trip to the moon with a crew of four would require: 24 gallons of drinking water for the crew and about 91 pounds of food(of which about 1 pound a day per person is containers). You could easily fit this much into a capsule. With a 6 day trip it probably cost less mass to use C02 scrubbing canisters and regenerate them when you get to a station in LLO or moon base or Lagraine point or just use the old disposable ones that the shuttle and craft before it use.

If you take 40 it jumps to about 160 gallons of water for a 40 day round trip and about 608 pounds of food. You have added over 1/4 ton worth of mass to the flight. And now need to be able to store all the stuff somewhere. Which means a bigger capsule or storage unit. You also probably need to bring a regenerative CO2 scrubbing system and consider water recyling.

In terms of radiation, you crew will be exposed to 6 times more radiation than a chemical one. In fact with radiation the longer you are exposed to it the worse the effects so a short dose is preferred over a longer one. And to my knowledge it is still impractical to bring enough radiation shielding to protect the crew from all radiation.

Unless you can cut the trip time down to about 5 days there just isn't much to gain from using a slower rocket to move people.
 
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DarkenedOne

Guest
edkyle99":2zyrwlkh said:
The CCCP tried, but never fully developed, this concept (unmanned tests flown as Zond capsules boosted by Blok D stages). I wonder why Russia hasn't tried it again, since Proton has grown up sufficiently to provide more orbital mass. I also wonder if China isn't working up to this type mission.

It is a neat stunt, one that might garner interest among Earthlings too young to remember Apollo, but no one would pay attention to the second mission, or the third, and so on.

People need to land, on the Moon. More than one geologist needs to walk there, dig there in more than one place. Someone needs to go see the frozen water and sift it through their gloved fingers.

- Ed Kyle
Historically NASA has been dominated by the fixed launch cost of their vehicles. Like the guy in charge of the shuttle program said it cost 200 million dollars per month just for the shuttle to operate. That is about 2.4 billion a year. It really does not change much if there are 4 flights or 12 flights.

However using commercial launchers negates the need for these incredibly expensive launchers that NASA builds so that more money can be spent on actual exploration. If the cost to get to the lunar surface we can conceivably build a moon base that is sustainable like the ISS, but probably at first a great deal smaller.
 
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DarkenedOne

Guest
Crossover_Maniac":f4ox23x5 said:
Ad Astra actually published a study in which it would take 180 days to get from LEO to LLO using current solar electric propulsion. For the same mass, six times the power could be generated by thin-film meaning six times the thrust and acceleration. This reduces that trip time from 180 days to 20 days. Trip time from LEO to LLO for Apollo was around three days. That's not that much of a difference, not with some of the recent advances in radiation shielding technology.
ESA's SMART-1 space probe was able to reach the moon in 1 month and 2 weeks with ion propulsion. The ion drive had a mass of 29 kg, required 1.2 kilowatts, and consumed 82 kg of Xenon. The mass of the probe was 287kg without propellant.

By comparison NASA wanted to ship about 34000kg using about 60000kg of propellant.

That is an immense improvement, especially since the costs of getting to orbit are so high.
 
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DarkenedOne

Guest
pathfinder_01":1uhtxre0 said:
The thing is the thrust of an electric rocket is determined by the amount of propellant expelled in a given time. You will either need an engine capable of handling six times more power, or six smaller ones to do it, or some combination of more engines. Either way odds are the mass of your craft has just increased which will slow it down a bit.

The other thing is the trip is a little more than 6 times longer than a chemical rocket. You now need 6 times the amount of food, water, oxygen, CO2 scrubing canisters ect. Or you will need to add water and reusable CO2 removal which take power, space, and equipment.

Using the ISS as an example a 6 day round trip to the moon with a crew of four would require: 24 gallons of drinking water for the crew and about 91 pounds of food(of which about 1 pound a day per person is containers). You could easily fit this much into a capsule. With a 6 day trip it probably cost less mass to use C02 scrubbing canisters and regenerate them when you get to a station in LLO or moon base or Lagraine point or just use the old disposable ones that the shuttle and craft before it use.

If you take 40 it jumps to about 160 gallons of water for a 40 day round trip and about 608 pounds of food. You have added over 1/4 ton worth of mass to the flight. And now need to be able to store all the stuff somewhere. Which means a bigger capsule or storage unit. You also probably need to bring a regenerative CO2 scrubbing system and consider water recyling.

In terms of radiation, you crew will be exposed to 6 times more radiation than a chemical one. In fact with radiation the longer you are exposed to it the worse the effects so a short dose is preferred over a longer one. And to my knowledge it is still impractical to bring enough radiation shielding to protect the crew from all radiation.

Unless you can cut the trip time down to about 5 days there just isn't much to gain from using a slower rocket to move people.
It is just like how it is here on earth. The key to cost savings is to ship humans and supplies separately. People are shipped by plane, which is the most expensive, but fastest for of transportation. Supplies on the other hand are shipped by truck, rail, or ship. These forms of transportation are slow, but they are the most cost efficient.



The cargo can be launched from cheaper, less reliable, commercial rockets. Cargo does not require life support. Cargo does not require radiation shielding. Cargo does not require artificial gravity. Cargo does not require any consumables. There is no problem with cargo in space for long durations.
 
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edkyle99

Guest
DarkenedOne":vdvrp61k said:
edkyle99":vdvrp61k said:
People need to land, on the Moon. More than one geologist needs to walk there, dig there in more than one place. Someone needs to go see the frozen water and sift it through their gloved fingers.
- Ed Kyle
Historically NASA has been dominated by the fixed launch cost of their vehicles. Like the guy in charge of the shuttle program said it cost 200 million dollars per month just for the shuttle to operate. That is about 2.4 billion a year. It really does not change much if there are 4 flights or 12 flights.

However using commercial launchers negates the need for these incredibly expensive launchers that NASA builds so that more money can be spent on actual exploration. If the cost to get to the lunar surface we can conceivably build a moon base that is sustainable like the ISS, but probably at first a great deal smaller.
Those "commercial" outfits will have their own fixed program costs. ULA, for example, gets something like $1-ish billion per year just to keep its launch pads and rocket factories open, whether it launches or not. (The Air Force said this week, BTW, that those fixed costs are going to increase significantly in the wake of the Constellation Cancellation.) The Shuttle program fixed costs are not just for the launch, but also for the astronauts, etc., something that ULA doesn't have to worry about (yet).

In broad, general terms, it costs X dollars to put a kilogram into orbit, regardless of who does the launching. NASA's real problem is that each Shuttle launch sends a lot of kilograms (more than 100,000 of them) into orbit, and thus costs a lot of dollars. The real reason that "commercial" crew launch would, or should, cost less is that ISS crew spacecraft are going to weigh one-tenth as much as a Shuttle orbiter. They should therefore cost one-tenth as much to launch, but that remains to be seen. NASA does not, for example, have to build a brand new Shuttle orbiter for each flight.

Going to the Moon is another matter. Although there are some clever ways to minimize the orbited mass needed for each lunar landing mission, the unavoidable truth is that a lot of mass, roughly the weight of 1.3 to 1.5 Shuttle-orbiters, is needed for each landing. Three-fourths of that mass is propellant. Another unavoidable truth is that more than one costly expendable spacecraft is needed for each lunar mission. Complex spacecraft, manned or unmanned, tend to cost on the order of a large fraction of a billion dollars per mission, each. In order to get to the Moon within existing budget limits, NASA will need to do the following.

1. Leverage the fixed costs of existing, or soon to exist, launch systems by using them for crewed missions.
2. Reduce annual budgets by reducing the total mass orbited each year compared to STS or Constellation.
3. Design slow-rate missions to efficiently use that mass.

One way to meet these requirements would be to use a storable LEO propellant depot that could gradually be filled over the course of many months, if not years. The depot could support a lunar landing mission once every 18 to 24 months, for example. Another way would be to launch lunar mission elements in pieces using existing cryogenic stages directly to L1, allowing the storable propellant elements to gradually assemble there, from where a lunar landing could periodically be staged.

Using these methods could allow an Apollo-class lunar mission to be staged with only five or six Delta 4 Heavy-class launches. If those launches could be spread over a couple of years (think about needing only one launch every four months), NASA could afford the mission - and the launch pad and crews would be able to support non-NASA missions during the launch campaign "gaps".

- Ed Kyle
 
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Valcan

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"Using these methods could allow an Apollo-class lunar mission to be staged with only five or six Delta 4 Heavy-class launches. If those launches could be spread over a couple of years (think about needing only one launch every four months), NASA could afford the mission - and the launch pad and crews would be able to support non-NASA missions during the launch campaign "gaps"."

Apollo is USELESS TODAY. we dont need apollo missions wana wave the flag say hey look at me go ahead use your own funds. We NEED a true pressence in space we need to MINE the moon not visit say hey check this out and leave.
 
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neutrino78x

Guest
DarkenedOne":1rfc5mmi said:
The cargo can be launched from cheaper, less reliable, commercial rockets. Cargo does not require life support. Cargo does not require radiation shielding. Cargo does not require artificial gravity. Cargo does not require any consumables. There is no problem with cargo in space for long durations.
Exactly, that's one of the major advantages of a Mars Direct, ISRU approach. You could use automated missions to set up the solar power and a robotic device to scoop up the lunar soil and generate fuel. Then you could send humans, with fuel for only one way, and they would use the fuel generated on the moon to go back.

Although this author on The Space Review feels that Lunar ISRU would not work well.

Still, even if you don't use the ISRU method, your idea is sound, in my opinion. We can take our time sending automated machines to set things up, then the humans are sent afterward.

--Brian
 
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edkyle99

Guest
Valcan":kil0i79h said:
"Using these methods could allow an Apollo-class lunar mission to be staged with only five or six Delta 4 Heavy-class launches. If those launches could be spread over a couple of years (think about needing only one launch every four months), NASA could afford the mission - and the launch pad and crews would be able to support non-NASA missions during the launch campaign "gaps"."

Apollo is USELESS TODAY. we dont need apollo missions wana wave the flag say hey look at me go ahead use your own funds. We NEED a true pressence in space we need to MINE the moon not visit say hey check this out and leave.
Apollo-class doesn't mean "flags and footprints". It means sortie missions. These missions can be longer-duration efforts than Apollo. There are good reasons to do such exploration missions. Humans have only seen six areas, all near the equator on the Earth-facing side of the Moon. Only one of the moon walkers was a geologist. The rest were essentially test pilots.

In case you haven't noticed, NASA isn't going to be given enough money to do a lunar base, let alone start mining the place! I would prefer sortie over nothing at all, which is the current post-Constellation plan.

- Ed Kyle
 
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neutrino78x

Guest
edkyle99":3q7k98gv said:
In case you haven't noticed, NASA isn't going to be given enough money to do a lunar base, let along start mining the place! I would prefer sortie over nothing at all, which is the current post-Constellation plan.
There is no reason sorties cannot lead to a developed base. However, I would suggest that NASA would not be doing any mining; that would be done by commercial interests. ISRU and mining are different. In fact, I'm not sure I would want any mining to be done on the Moon. It would bring up the question of where the profit should go, since, in my opinion, as the Moon orbits the Earth, it should belong to mankind collectively. So, is the UN going to get the profits from mining? I see the Moon as being like Antarctica; the places I think we should colonize/mine are Mars, the asteroids, moons of other planets, etc.

--Brian
 
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