post Constellation plans

[halman]

We currently are spending about 6 billion dollars a year on manned space exploration. That is simply not enough. We need to budget at least 10 billion a year for at least the next 25 years if we want to see any real progress. By real progress I mean missions to the Moon that last at least a couple of months, are capable of drilling core samples a kilometer deep or more, and experiment with excavation and burial of habitat. Also, development of long-duration closed-loop life support systems, magnetic radiation shielding, and advanced propulsion systems. Construction of a new, improved space station, able to support multiple missions, including Moon, Mars, and Near Earth Objects.

When building step rockets, bigger is better. Because the larger the rocket, the better the efficiency. This is why I advocate a small, airborne launched crew shuttle used in conjunction with a very large heavy lift booster, as well as Orbital Transfer Vehicles.

We need to do space research in space, not by remote control on the ground, or in vacuum chambers. We need to learn how to deflect radiation, rather than absorb it. The high energy particles the Sun emits cause cascades of secondary radiation when they strike dense, heavy material, because that material has lots of neutrons. The crew on the International Space Station can spend months up there without serious exposure issues because they are inside the Earth's radiation shield, the Van Allen belts. These magnetic fields deflect the radiation into away from the surface, while acting to ground the energy at the planet's poles, if I understand the physics properly. This principle is the only way to effectively shield craft outside of the Van Allen belts over long periods of time, because the matter used in shielding eventually becomes radioactive itself, as a result of the constant bombardment.

Everyone is all excited about going somewhere in space, but space itself is a destination, one which we are just barely beginning to understand how to survive in. Inflatable habitats are great for being able to send them somewhere cheaply, but they are not going to be useful for any long-term existence in space, at least until we can shield the occupants from the various radiations in space. This is why digging in is so important, both on the Moon and on Mars, because that is the only way that we can be assured of having protection not only from radiation, but from incoming rocks, as well.

 

[Tritium]

We currently are spending about 6 billion dollars a year on manned space exploration. That is simply not enough. We need to budget at least 10 billion a year for at least the next 25 years if we want to see any real progress. By real progress I mean missions to the Moon that last at least a couple of months, are capable of drilling core samples a kilometer deep or more, and experiment with excavation and burial of habitat. Also, development of long-duration closed-loop life support systems, magnetic radiation shielding, and advanced propulsion systems. Construction of a new, improved space station, able to support multiple missions, including Moon, Mars, and Near Earth Objects.

When building step rockets, bigger is better. Because the larger the rocket, the better the efficiency. This is why I advocate a small, airborne launched crew shuttle used in conjunction with a very large heavy lift booster, as well as Orbital Transfer Vehicles.

We need to do space research in space, not by remote control on the ground, or in vacuum chambers. We need to learn how to deflect radiation, rather than absorb it. The high energy particles the Sun emits cause cascades of secondary radiation when they strike dense, heavy material, because that material has lots of neutrons. The crew on the International Space Station can spend months up there without serious exposure issues because they are inside the Earth's radiation shield, the Van Allen belts. These magnetic fields deflect the radiation into away from the surface, while acting to ground the energy at the planet's poles, if I understand the physics properly. This principle is the only way to effectively shield craft outside of the Van Allen belts over long periods of time, because the matter used in shielding eventually becomes radioactive itself, as a result of the constant bombardment.

Everyone is all excited about going somewhere in space, but space itself is a destination, one which we are just barely beginning to understand how to survive in. Inflatable habitats are great for being able to send them somewhere cheaply, but they are not going to be useful for any long-term existence in space, at least until we can shield the occupants from the various radiations in space. This is why digging in is so important, both on the Moon and on Mars, because that is the only way that we can be assured of having protection not only from radiation, but from incoming rocks, as well.

After reading everyone's posts,it appears that the knowledge and the technology exists to build a comprehensive manned space program.The large boulder in the road is money to pay for the implementation of such a program.

It also appears that in order to stimulate funding,we need to educate the public about the numerous reasons such a comprehensive program which included a Lunar,and Martian Colony,would be beneficial to humanity.

The continued use of the current shuttles,with upgrades and combined with heavy lift rockets and cargo capsules to build a new LEO space station which could then assemble,fuel,and repair large spaceships.These spacecraft would use VASMIR engines and generate magnetic deflection shields to protect the crew(which would be much larger than 7)from radiation outside the Van Alan Belt of the Earth.Orbital Transfer Vehicles ("space tugs") would tow the newly assembled craft to a higher orbit,where it could begin it's journey to Mars.And upon return,be captured,or transfer crew and cargo.A Lunar Colony would be built,using buried inflatable habitat modules.Drilling and mining ,harvesting water,helium,making fuel,growing food,and doing research to develop further advances.All of this leading to the construction of a Martian Colony,which would use much the same techniques as the Lunar Colony for it's establishment,and sustained self-sufficiency.

Very,very cool.Let's git er done! :ugeek:

 

[edkyle99]

We currently are spending about 6 billion dollars a year on manned space exploration. That is simply not enough. We need to budget at least 10 billion a year for at least the next 25 years if we want to see any real progress.

I agree completely!

Unfortunately, political realities being what they are, it seems that NASA will not be seeing big budget increases. The Agency, it appears, needs to plan for lower-cost programs. Right now, that means ISS and LEO-only for humans.

I would like to see NASA work up a lower-cost program proposal for lunar exploration. One approach, as I've suggested, might be to stretch out the missions, flying infrequently perhaps through the use of a LEO propellant depot. Another approach might be to shrink the hardware, reducing mass and limiting functionality, etc. Perhaps the "commercial" approach could offer another cost-reduction method.

Good engineering also addresses the cost question. What ideas might readers of this forum have in that regard?

- Ed Kyle

 

[Tritium]

We currently are spending about 6 billion dollars a year on manned space exploration. That is simply not enough. We need to budget at least 10 billion a year for at least the next 25 years if we want to see any real progress.

I agree completely!

Unfortunately, political realities being what they are, it seems that NASA will not be seeing big budget increases. The Agency, it appears, needs to plan for lower-cost programs. Right now, that means ISS and LEO-only for humans.

I would like to see NASA work up a lower-cost program proposal for lunar exploration. One approach, as I've suggested, might be to stretch out the missions, flying infrequently perhaps through the use of a LEO propellant depot. Another approach might be to shrink the hardware, reducing mass and limiting functionality, etc. Perhaps the "commercial" approach could offer another cost-reduction method.

Good engineering also addresses the cost question. What ideas might readers of this forum have in that regard?

- Ed Kyle

To stop spending money for war,and the weaponry of war.

 

[pathfinder_01]

We currently are spending about 6 billion dollars a year on manned space exploration. That is simply not enough. We need to budget at least 10 billion a year for at least the next 25 years if we want to see any real progress.

I agree completely!

Unfortunately, political realities being what they are, it seems that NASA will not be seeing big budget increases. The Agency, it appears, needs to plan for lower-cost programs. Right now, that means ISS and LEO-only for humans.

I would like to see NASA work up a lower-cost program proposal for lunar exploration. One approach, as I've suggested, might be to stretch out the missions, flying infrequently perhaps through the use of a LEO propellant depot. Another approach might be to shrink the hardware, reducing mass and limiting functionality, etc. Perhaps the "commercial" approach could offer another cost-reduction method.

Good engineering also addresses the cost question. What ideas might readers of this forum have in that regard?

- Ed Kyle

The thing is with technology you might not need to reduce functionality at all. For instance the Sarturn V 3rd stage weight about 25,000 pound empty. A Delta IV heavy could put a stage that massed that much into LEO if it were empty. With a fuel depo the problem then becomes how do you get about 118 tons of proplent into LEO. If Nasa builds a heavy lift like the Saturn V(about 200,000 pounds to leo), you could get 2 lunar trips for each heavy lift launch. Although the Heavy lift will be expensive, the Delta IV will be cheap. Even if the heavy lift were as expensive as the shuttle, you still get more bang for the buck this way.

 

[pathfinder_01]

We currently are spending about 6 billion dollars a year on manned space exploration. That is simply not enough. We need to budget at least 10 billion a year for at least the next 25 years if we want to see any real progress.

I agree completely!

Unfortunately, political realities being what they are, it seems that NASA will not be seeing big budget increases. The Agency, it appears, needs to plan for lower-cost programs. Right now, that means ISS and LEO-only for humans.

I would like to see NASA work up a lower-cost program proposal for lunar exploration. One approach, as I've suggested, might be to stretch out the missions, flying infrequently perhaps through the use of a LEO propellant depot. Another approach might be to shrink the hardware, reducing mass and limiting functionality, etc. Perhaps the "commercial" approach could offer another cost-reduction method.

Good engineering also addresses the cost question. What ideas might readers of this forum have in that regard?

- Ed Kyle

The thing is with technology you might not need to reduce functionality at all. For instance the Sarturn V 3rd stage weight about 25,000 pound empty. A Delta IV heavy could put a stage that massed that much into LEO if it were empty. With a fuel depo the problem then becomes how do you get about 118 tons of proplent into LEO. If Nasa builds a heavy lift like the Saturn V(about 200,000 pounds to leo), you could get 2 lunar trips for each heavy lift launch. Although the Heavy lift will be expensive, the Delta IV will be cheap. Even if the heavy lift were as expensive as the shuttle, you still get more bang for the buck this way.

 

[Tritium]

We currently are spending about 6 billion dollars a year on manned space exploration. That is simply not enough. We need to budget at least 10 billion a year for at least the next 25 years if we want to see any real progress.

I agree completely!

Unfortunately, political realities being what they are, it seems that NASA will not be seeing big budget increases. The Agency, it appears, needs to plan for lower-cost programs. Right now, that means ISS and LEO-only for humans.

I would like to see NASA work up a lower-cost program proposal for lunar exploration. One approach, as I've suggested, might be to stretch out the missions, flying infrequently perhaps through the use of a LEO propellant depot. Another approach might be to shrink the hardware, reducing mass and limiting functionality, etc. Perhaps the "commercial" approach could offer another cost-reduction method.

Good engineering also addresses the cost question. What ideas might readers of this forum have in that regard?

- Ed Kyle

The thing is with technology you might not need to reduce functionality at all. For instance the Sarturn V 3rd stage weight about 25,000 pound empty. A Delta IV heavy could put a stage that massed that much into LEO if it were empty. With a fuel depo the problem then becomes how do you get about 118 tons of proplent into LEO. If Nasa builds a heavy lift like the Saturn V(about 200,000 pounds to leo), you could get 2 lunar trips for each heavy lift launch. Although the Heavy lift will be expensive, the Delta IV will be cheap. Even if the heavy lift were as expensive as the shuttle, you still get more bang for the buck this way.

This is the way we'll get er done folks.One idea,one step,another idea,another step.Just keep moving,thinking,growing towards the goal!

 

[edkyle99]

To stop spending money for war,and the weaponry of war.

We all look forward to the end of the wars, but I'm not sure that squeezing one of the two budgets (NASA or Department of Defense) will necessarily benefit the other under this Administration. The Obama White House has already canceled a number of high-profile Pentagon programs. Now it is doing the same with NASA.

Keep in mind, too, that the largest share of U.S. space spending is actually in the DoD budget.

- Ed Kyle

 

[neutrino78x]

You don't have to build the Starship Enterprise to make a permanent US Territory on Mars. See Mars Direct. Two heavy lift launches for each group of people; the first one goes to Mars to generate the fuel for the return trip; the second one brings the people, and enough fuel for a one way journey. You could do it with smaller vehicles that only get launched to LEO, also, then assemble in orbit and go to Mars. Although Robert Zubrin says in his book that it takes less delta V to just directly there.

--Brian

 

[Tritium]

You don't have to build the Starship Enterprise to make a permanent US Territory on Mars. See Mars Direct. Two heavy lift launches for each group of people; the first one goes to Mars to generate the fuel for the return trip; the second one brings the people, and enough fuel for a one way journey. You could do it with smaller vehicles that only get launched to LEO, also, then assemble in orbit and go to Mars. Although Robert Zubrin says in his book that it takes less delta V to just directly there.

--Brian

It doesn't have to be U.S. Territory.
We have to start thinking of ourselves as "Earthlings".
In other words,we are the species of mankind.
It will take all of us,together,to do this.
And yes,multiple launches,assembled in space,large crews,advanced landers which can land and take off,then get re-supplied,then land again,and take off again.Larger and larger ships to bring more and more people and equipment to each colony throughout the system.

 

[HopDavid]

You don't have to build the Starship Enterprise to make a permanent US Territory on Mars. See Mars Direct. Two heavy lift launches for each group of people; the first one goes to Mars to generate the fuel for the return trip; the second one brings the people, and enough fuel for a one way journey. You could do it with smaller vehicles that only get launched to LEO, also, then assemble in orbit and go to Mars. Although Robert Zubrin says in his book that it takes less delta V to just directly there.

--Brian

So what do you get after 40 years of Mars Direct? Maybe 20 habs. Nothing remotely close to a viable colony and no exports back to Earth.

The 21st century Nixon will look at the several hundred billion dollar price tag and ask what we're getting for the money. The president and congress will quietly ax this 21st century Apollo. A few space enthusiasts will holler but most folks won't even notice.

Mars Direct isn't a sustainable architecture.

 

[Tritium]

You don't have to build the Starship Enterprise to make a permanent US Territory on Mars. See Mars Direct. Two heavy lift launches for each group of people; the first one goes to Mars to generate the fuel for the return trip; the second one brings the people, and enough fuel for a one way journey. You could do it with smaller vehicles that only get launched to LEO, also, then assemble in orbit and go to Mars. Although Robert Zubrin says in his book that it takes less delta V to just directly there.

--Brian

So what do you get after 40 years of Mars Direct? Maybe 20 habs. Nothing remotely close to a viable colony and no exports back to Earth.

The 21st century Nixon will look at the several hundred billion dollar price tag and ask what we're getting for the money. The president and congress will quietly ax this 21st century Apollo. A few space enthusiasts will holler but most folks won't even notice.

You have no vision,and no faith in anything.We will see the need to establish colonies in space,to preserve our species,and once we "GET IT" we will work as a "United Earth" to preserve our species,and to reach ever farther into our solar system.There will be countless benefits as a result,and profits will be seen as never before.You short-sighted materialistic folks really make me wish I could wake you from the depths of your world view,which is limited,and antiquated.

Mars Direct isn't a sustainable architecture.

 

[edkyle99]

The thing is with technology you might not need to reduce functionality at all. For instance the Sarturn V 3rd stage weight about 25,000 pound empty. A Delta IV heavy could put a stage that massed that much into LEO if it were empty. With a fuel depo the problem then becomes how do you get about 118 tons of proplent into LEO. If Nasa builds a heavy lift like the Saturn V(about 200,000 pounds to leo), you could get 2 lunar trips for each heavy lift launch. Although the Heavy lift will be expensive, the Delta IV will be cheap. Even if the heavy lift were as expensive as the shuttle, you still get more bang for the buck this way.

The S-IVB stage, at least the Apollo 17 AS-514 S-IVB stage (including its Instrument Unit), weighed 16.2 tonnes (35,721 lbs) after its TLI burn, including residuals. It carried about 75.13 tonnes of propellant into its initial parking orbit, for a total 91.24 tonne stage weight in orbit. It boosted a combined 48.601 tonne CSM/LM spacecraft mass from LEO toward the Moon. Thus Saturn V had to lift roughly 140 tonnes to the initial low earth parking orbit.

Let's back up from that 48.601 tonne Apollo TLI mass for a minute and try to re-create Apollo, for argument's sake.

Using a modern upper stage designed just for the TLI task, and powered by a more efficient RL10 cluster (450 sec specific impulse rather than the 421 sec J-2 ISP), would reduce the parking orbit requirement from 140 tonnes to only 111 tonnes! The TLI propellant mass would be reduced to only 56 tonnes from Apollo 17's roughly 77 tonnes.

How to get the 111 tonnes to LEO? Shuttle-derived might get there, but the effort will require funding. With the already-funded RS-68A upgrade, Delta IV Heavy LEO capability is supposed to increase to 27.5 tonnes. Four D4 Heavy launches augmented by one smaller vehicle launch could meet the 111 tonne requirement. Five D4 Heavies would easily top the mark (and nearly match Saturn V). Either way, five launches, and the development of a new propellant depot system, are needed.

This plan either requires a surge launch approach to minimize propellant boil-off or the development of a new heavy lifter. That means new pads and/or big money, increasing the cost of launching Delta 4 or paying for launching very small numbers of very big rockets. So let us now consider an all-storable propellant "Plan B".

Russia's Briz M upper stage engine provides the world's most efficient storable propellant specific impulse, as I understand it, at about 326 seconds. The best in the U.S. is, I believe, the Delta 2 upper stage at about 319 seconds.

If the U.S. could develop a 326 sec ISP storable propellant TLI stage engine, a 48.601 tonne TLI mass would require use of a 100 tonne gross mass TLI stage loaded with 92.2 tonnes of storable propellant (something roughly the size and mass of a loaded Titan 2 first stage). The total LEO mass requirement climbs to nearly 149 tonnes, 9 tonnes more than for an Apollo mission, but the cryogenic boil-off concerns vanish. Six Delta 4 Heavy launches are now needed, but without a launch surge requirement, the flights can occur at a more leisurely, affordable pace. It one lunar mission were performed every other year, NASA would only have to fund three Delta 4 Heavy launches in any given annual budget! That's less payload to LEO than that now provided by NASA's soon-to-be-retired Shuttle fleet - and for less money (at least on the launch-cost side)!

Problem solved! To the Moon!

- Ed Kyle

 

[pathfinder_01]

If the U.S. could develop a 326 sec ISP storable propellant TLI stage engine, a 48.601 tonne TLI mass would require use of a 100 tonne gross mass TLI stage loaded with 92.2 tonnes of storable propellant (something roughly the size and mass of a loaded Titan 2 first stage). The total LEO mass requirement climbs to nearly 149 tonnes, 9 tonnes more than for an Apollo mission, but the cryogenic boil-off concerns vanish. Six Delta 4 Heavy launches are now needed, but without a launch surge requirement, the flights can occur at a more leisurely, affordable pace. It one lunar mission were performed every other year, NASA would only have to fund three Delta 4 Heavy launches in any given annual budget! That's less payload to LEO than that now provided by NASA's soon-to-be-retired Shuttle fleet - and for less money (at least on the launch-cost side)!

Problem solved! To the Moon!

- Ed Kyle

From what I have heard, a lox/kerosene engine could do it. Plus Kerosene has no boil off problems. In addition the TLI stage would likely be lighter empty than if it used hydrogen.

Another thought, if you launched the Lander with either the decent or accent stage empty you and refuel at the moon you could save mass. The fuel at the moon could be moved via a solar powered electric tug. I wouldn’t want to take the risk of not having any propellant in the Lander in case you have an Apollo 13 moment. However you could save weight this way. You could also refuel the Lander at the depot in earth orbit saving again on the amount of mass needed to be put in Leo allowing the use of a smaller launcher.

Also how much propellant is needed to escape from the moon? Could a decent stage provide enough delta V to escape from the moon allowing the service module to contain only enough propellant to brake into lunar orbit?

I think the amount needed to be inserted in orbit at the moon could be less than 48 tons without giving up too much.
As for one flight every other maybe not. If a rocket that puts up 50-80 tons a launch is developed you could put the 92 tons of propellant in two launches. There is funding for HLV research at the moment and I wouldn’t be surprised if funding becomes available. A shuttle derived HLV could be easily developed in that range. Now you could have at least one mission a year and this rocket could be useful for supporting the ISS.

 

[HopDavid]

You have no vision,

Since I don't share your vision, I have no vision. OK.

and no faith in anything.We will see the need to establish colonies in space,to preserve our species,and once we "GET IT" we will work as a "United Earth" to preserve our species,and to reach ever farther into our solar system.

I believe we should colonize to preserve our species and reach ever farther into the solar system.

But what does congress think? Do you think that one fine morning our representatives will wake up and see the light?

And then they will shovel 100s of billions into one of the more boneheaded and wasteful architectures for human settlement of space?

There will be countless benefits as a result,and profits will be seen as never before.You short-sighted materialistic folks really make me wish

Your intense wishfulness won't change congress. Sorry to break the news.

I could wake you from the depths of your world view,which is limited,and antiquated.

You have no clue what my world view is.

 

[edkyle99]

If the U.S. could develop a 326 sec ISP storable propellant TLI stage engine, a 48.601 tonne TLI mass would require use of a 100 tonne gross mass TLI stage loaded with 92.2 tonnes of storable propellant (something roughly the size and mass of a loaded Titan 2 first stage). The total LEO mass requirement climbs to nearly 149 tonnes, 9 tonnes more than for an Apollo mission, but the cryogenic boil-off concerns vanish. Six Delta 4 Heavy launches are now needed, but without a launch surge requirement, the flights can occur at a more leisurely, affordable pace. It one lunar mission were performed every other year, NASA would only have to fund three Delta 4 Heavy launches in any given annual budget! That's less payload to LEO than that now provided by NASA's soon-to-be-retired Shuttle fleet - and for less money (at least on the launch-cost side)!

Problem solved! To the Moon!

- Ed Kyle

From what I have heard, a lox/kerosene engine could do it. Plus Kerosene has no boil off problems. In addition the TLI stage would likely be lighter empty than if it used hydrogen.

LOX/kerosene would be denser than LOX/LH2, but there would still be a boil-off problem with the LOX. Storables would be denser than both. The LOX would weigh nearly twice as much as the kerosene, so would require more launches than the kerosene in a depot architecture, getting us back to the surge-launch problem.

...
As for one flight every other maybe not. If a rocket that puts up 50-80 tons a launch is developed you could put the 92 tons of propellant in two launches. There is funding for HLV research at the moment and I wouldn’t be surprised if funding becomes available. A shuttle derived HLV could be easily developed in that range. Now you could have at least one mission a year and this rocket could be useful for supporting the ISS.

I would love to see funding for launch vehicle development, but we've just seen NASA's only launch vehicle development programs canceled. In the current political environment, I've accepted the fact that heavy lift isn't going to happen - at least not any time soon. That's why I'm "thinking small", using existing launch vehicles with an architecture that can operate with low-launch rates over many months for each mission.

- Ed Kyle

 

[rockett]

I would love to see funding for launch vehicle development, but we've just seen NASA's only launch vehicle development programs canceled. In the current political environment, I've accepted the fact that heavy lift isn't going to happen - at least not any time soon. That's why I'm "thinking small", using existing launch vehicles with an architecture that can operate with low-launch rates over many months for each mission.

- Ed Kyle

Has anybody thought about ULA licensing construction of Ariane 5s? They have done that with military aircraft for decades. It would give us something until we could do better...

 

[EarthlingX]

I would love to see funding for launch vehicle development, but we've just seen NASA's only launch vehicle development programs canceled. In the current political environment, I've accepted the fact that heavy lift isn't going to happen - at least not any time soon. That's why I'm "thinking small", using existing launch vehicles with an architecture that can operate with low-launch rates over many months for each mission.

- Ed Kyle

Has anybody thought about ULA licensing construction of Ariane 5s? They have done that with military aircraft for decades. It would give us something until we could do better...

A little background on this question, from SpaceRef, 2001 :
Spacelift Washington: International Space Transportation Association Faltering; The myth of $10,000 per pound

Frank Sietzen, Jr.
Sunday, March 18, 2001

WASHINGTON - Boeing and Lockheed Martin have declined again to join a proposed international space launch trade group, this column has learned. And without at least one of the major U.S. space launch firms as members, the proposed organization, the International Space Transportation Association, will be unable to get underway. The decision effectively ends any chance of establishment of the ISTA in the near term, according to Doug Heydon, former President of Arianespace Inc. and original supporter of the concept of a global trade association for space launch service providers.

 

[pathfinder_01]

LOX/kerosene would be denser than LOX/LH2, but there would still be a boil-off problem with the LOX. Storables would be denser than both. The LOX would weigh nearly twice as much as the kerosene, so would require more launches than the kerosene in a depot architecture, getting us back to the surge-launch problem.

...
As for one flight every other maybe not. If a rocket that puts up 50-80 tons a launch is developed you could put the 92 tons of propellant in two launches. There is funding for HLV research at the moment and I wouldn’t be surprised if funding becomes available. A shuttle derived HLV could be easily developed in that range. Now you could have at least one mission a year and this rocket could be useful for supporting the ISS.

I would love to see funding for launch vehicle development, but we've just seen NASA's only launch vehicle development programs canceled. In the current political environment, I've accepted the fact that heavy lift isn't going to happen - at least not any time soon. That's why I'm "thinking small", using existing launch vehicles with an architecture that can operate with low-launch rates over many months for each mission.

- Ed Kyle

I think the boil off problem could be manageable and the density problem perhaps solved by shipping oxygen in a solid state. A propellant depot could have equipment to keep the oxygen in a liquid state. Complex for sure but if don't develop technology in the way Apollo did we are stuck in LOE. Since the propellant depot is not going anywhere much more insulation could be used than in a rocket. If I am reading things right there are oxygen tanks on the ground with boil of rates of .12% a day. Granted I think that the boil of rate probably increases as the tank empties and you get no where near that claim but most of the claims I read where less than 1% a day. I even had once source claim as low as .016% for a tank in leo without a sun shade and that you could use the boil of of liquid hydrogen to refrigerate the oxygen. I also suspect that liquid nitrogen might work as well because it is colder than oxygen. http://www.dunnspace.com/cryogen_space_storage.htm. I just wish I could verify his information.

Also the more efficient the rocket fuel the propellant the less mass of it we need to ship(of course the weight of the insulation\tankage could cut into that....). If I am reading things right LOX/Kerosene is a bit more efficient than hypergolics.

Anyway back to our 48.6 ton CM/LM craft and using your stored hypergolic propelents. How much lunar injection propelent would be saved if 5,198 pounds or 2.5 short tons of accent stage proplent were removed from the amount needed both to be sent to the moon and braked into lunar orbit? How much could be saved if 9 tons(the decent module propelent?)

How much could be saved if decent engine on the lander could be used in full or in partial to help return the astronauts to earth if the proplent transfer failed? In this senrio I am imagining a CM that only had enough propelent to brake into lunar orbit but not return without a fill up.

Just to keep it simple we could use the 1960ies propelents and engines...I think we could probably do better today. My goal is to keep the astronaunts safe while removing some proplent mass. If you could refuel at the moon you don't need to carry the fuel to return with you, but should you not be able to refuel you do. If you could lower the mass from 48 tons you don't need to so much propelent for your Lunar injection stage and if you don't need to brake the mass of the propelent removed you gain some more. Finaly if the command module didn't need to carry the full amount needed for the return trip you gain again. Ofcourse this is offset by needing to ship proplent to the moon, but I think that even if you used a chemical booster it could be worth it.

 

[EarthlingX]

Lori Garver about future NASA plans, from SpaceRef :

Speech by NASA Deputy Administrator Lori Garver - Women In Aerospace Breakfast March 4, 2010

Date Released: Friday, March 12, 2010
Source: NASA HQ

It's my pleasure to be here today. This organization has been important to me throughout my career. It's been a major resource and support group (something that has come in handy at different points in my career), and I have met many people through WIA who have become lifelong friends and colleagues. WIA held my baby shower for Wes (Pam Mountjoy) and when he was 8 days old, Wes attended his first WIA event at the National Air and Space Museum (he received at least one marriage proposal that night - don't tell Paula Korn he turns 18 on Tuesday (where he will again be attending a space event with his mother and father...)

 

[rockett]

A little background on this question, from SpaceRef, 2001 :
Spacelift Washington: International Space Transportation Association Faltering; The myth of $10,000 per pound

Frank Sietzen, Jr.
Sunday, March 18, 2001

WASHINGTON - Boeing and Lockheed Martin have declined again to join a proposed international space launch trade group, this column has learned. And without at least one of the major U.S. space launch firms as members, the proposed organization, the International Space Transportation Association, will be unable to get underway. The decision effectively ends any chance of establishment of the ISTA in the near term, according to Doug Heydon, former President of Arianespace Inc. and original supporter of the concept of a global trade association for space launch service providers.

Good grief! Sometimes I think we are our own worst enemy when it comes to getting things done...

 

[halman]

Investment in space technology is not going to come about because of the desire to establish colonies on Mars. That will happen when the wealth created by utilizing space as an industrial zone reaches the point where the colonization of Mars will represent only a small fraction of what is being spent in space.

As long as space exploration is viewed as purely scientific research, in the same category as the Large Hadron Collider, we will not see a substantial increase in spending. What is needed is a shift in perspective, a recognition that the automobile industry is not going to rescue the American economy. What has been spent saving two American car companies would have gone the majority of the way toward developing a two-stage to-orbit space shuttle to be used purely for carrying people into Low Earth Orbit.

There is about 6 trillion dollars in investment capital currently tied up in equity markets. Shifting some of that into space development should not be difficult, if we can present a united front advocating the creation of jobs in the aerospace industry, the development of new products for use on Earth, and the environmental benefits of lifting heavy industry off of Earth into space. Space has got to be viewed as an arena for industrial development first, before we purpose colonizing Mars, the Moon, or the stars.

Talk of building colonies on the Moon, or terraforming Mars scares away the people who are willing to invest in start-up technology, because they see no return for their investment. We have to emphasize the possibilities of zero-gravity manufacturing, free energy, and resources which can be harvested without environmental costs or the opposition of the locals. Those who focus on the romantic prospects of space exploration, the living on other planets, are preventing the focus on the business prospects of space exploration. The development of space for industrial purposes will result in many of the technologies needed for extra-terrestrial colonization being perfected by industry at their cost to enable the creation of factories in space, mines on the Moon, and missions to Near Earth Objects to prospect for resources.

 

[neutrino78x]

So what do you get after 40 years of Mars Direct? Maybe 20 habs. Nothing remotely close to a viable colony and no exports back to Earth.

The 21st century Nixon will look at the several hundred billion dollar price tag and ask what we're getting for the money. The president and congress will quietly ax this 21st century Apollo. A few space enthusiasts will holler but most folks won't even notice.

Mars Direct isn't a sustainable architecture.

Mars Direct is a highly sustainable architecture. You are again assuming that we are only doing science on Mars. My purpose for going to Mars is not science, but colonization. After 40 years, I expect there to be private land owners on Mars, trading with each other.

See this Robert Zubrin paper on the economic viability of a Mars colony.

The habs link together. After several missions, you should have a good sized base, and you can start sending larger ships, with colonists. You sell the land from Earth, generating billions of dollars. You also sell Mars rocks and regolith to collectors, etc. You may find concentrated mineral deposits which you can sell to Earth, etc.

Zubrin's book, The Case for Mars, goes into great detail about this.

--Brian

 

[edkyle99]

I think the boil off problem could be manageable and the density problem perhaps solved by shipping oxygen in a solid state. .... If I am reading things right there are oxygen tanks on the ground with boil of rates of .12% a day. Granted I think that the boil of rate probably increases as the tank empties and you get no where near that claim but most of the claims I read where less than 1% a day. I even had once source claim as low as .016% for a tank in leo without a sun shade and that you could use the boil of of liquid hydrogen to refrigerate the oxygen. I also suspect that liquid nitrogen might work as well because it is colder than oxygen. http://www.dunnspace.com/cryogen_space_storage.htm. I just wish I could verify his information.

ULA's propellant depot proposal included rapid transfer of propellant from LEO to an L-point depot to reduce boil off, which occurs more rapidly in LEO. If ULA couldn't design an all-LEO depot mission using LOX/LH2, I doubt it can be done easily.

Hypergolic storables eliminate the ticking clock "use it or lose it" propellant storage problem, and make a LEO depot achievable.

A challenge would be propulsion. A few years ago, the U.S. a pump-fed engine that would have worked, the LR91-AJ-11 engine used by the Titan IV second stage. It provided 48 tonnes thrust at 316 sec ISP. NASA would have to resurrect that engine, or something similar, to power a TLI stage. NASA also needs to save and preserve the AJ10-series pressure-fed engine program, very soon, to provide propulsion for crew and landing modules.

- Ed Kyle

 

[halman]

Constellation was a scam, the most expensive rocket possible with the least investment in Research And Development. It did not even try to move away from using shuttle/Apollo support infrastructure, it was simply a sop to popular sentiment for space exploration while avoiding increasing spending.

Thankfully, that scam was seen through, and it is in the process of being exposed, so that it will be stopped. But Congress has been in on the deception from the git-go, and is interested in keeping jobs in home districts, not in doing what is right.

What would be right is easy to describe, Heavy Lift Launch Vehicles, capable of putting 100 tons or more in Low Earth Orbit, using kerosene and lox, because we know how to, and don't need every possible once of thrust to get three guys to the Moon and back. Hydrogen is used because it is the ultimate, but it is expensive, and difficult to handle, and is hard to store. If our second stage is going to use kerosene and liquid oxygen, than we will need a bigger first stage. We won't need a third stage, because we won't be going any higher than LEO. If we need to send something somewhere, we build a ship to take it there, instead of trying to launch it from Earth.

When we go somewhere, we do it by sending what we are going to need, not what we can pack into a single can which we hurl all the way from Earth. So, we assemble stuff in LEO, and then haul it to the Moon in a rocket that we will use over and over again. We have got to get this Apollo kind of thinking out of our minds, because it is an impediment to selling the case for space exploration. If we are going to go somewhere, why do we have to throw things away to get there? We don't do that going anywhere else, do we? We have got to stop talking about scraping together a mission that requires fuel to be processed where we are going, by robots, before we get there, so that we will have some way to get back, because that makes us look desperate to get away from the people who are going to pay for all of this.

Development has to be sustainable, goal oriented, and potentially profitable, or it is not going to happen. I want more than anything else to see a human presence on the Earth's moon, but that is not what I am going to agitate for, because people don't see any money in that right now. But if we are talking about processing material mined on the Moon in space to sell on Earth, then their ears perk up. What kind of things, they wonder?

Foamed metals, annealed for several weeks, reinforced with carbon filaments, maybe, or foamed ceramics, ditto, and ditto, which would be lightweight, strong, and durable. It costs thousands of dollars to replace a roof on a home, and that roof will only last 20 or 25 years, even if it is the best roofing material available. What if there were ceramic roofing tiles light enough to put on a roof without that roof having to be reinforced? What if those tiles would last 100 years? How much would they be worth? How much would a wrench that will float on water be worth, if it is several times stronger than any wrench made on Earth? What would a room-temperature super conductor be worth?

When we start talking about space this way, then people begin to get interested. They see that money could be made out there. They realize that we don't have to spend billions and billions of dollars with no hope of any return. Sure, it is going to take a while before anybody gets rich off of space, but it will happen. It will, that is, if we stop talking about using exotic fuels and highly advanced engineering just so that a few people can go to Mars. Someday.

If we want people to invest in space exploration, we have to talk about what we can do right now, with common, ordinary rockets, that burn stuff that doesn't have to be kept a couple of degrees above absolute zero to keep it from boiling away. We have to talk about energy being free, and what we can do in zero gravity that we already know about, and how things can be made up there that we cannot make here on Earth. Things that people will pay a lot of money for.Because money is what it is all about now, not national prestige, not one-upsmanship, but investment with the expectation of realizing a profit.

There is right around 6 trillion dollars in money that is invested in stock markets, bonds, and and other financial instruments in the world, and most of it is looking for a higher return. If we can only convince a small portion of that 6 trillion to invest in space, we will have heavy lift launch vehicles, crew shuttles, Orbital Transfer Vehicles, Lunar shuttles, and the lot, someday soon. We can get the technology for keeping people alive in space for long periods of time perfected, we can get methods of shielding against radiation developed, we can figure out how to do things out there. Once we learn those things, than it will be far easier and much cheaper to go to places like Mars, or Venus, and get killed learning how to survive there.