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#76 2014-06-14 12:06:23

RGClark
Member
From: Philadelphia, PA
Registered: 2006-07-05
Posts: 501
Website

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

The Project Morpheus lunar lander has succeeded better than NASA expected - or intended. It was supposed to be only for landing small, robotic probes on the Moon. However, by scaling it up three times or by connecting three original-sized ones together, it can serve as the descent stage of a manned lander, with a single copy of the original one serving as the ascent stage. This would be for a development cost of a few 10's of millions of dollars, orders of magnitude cheaper than the $10 billion Altair lunar lander.

The Morpheus lunar lander as manned lander for the Moon.
http://exoscientist.blogspot.com/2014/0 … anned.html


   Bob Clark


Nanotechnology now can produce the space elevator and private orbital launchers. It now also makes possible the long desired 'flying cars'. This crowdfunding campaign is to prove it:
Nanotech: from air to space.
https://www.indiegogo.com/projects/nano … 13319568#/

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#77 2014-06-14 12:43:10

RGClark
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From: Philadelphia, PA
Registered: 2006-07-05
Posts: 501
Website

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

The National Research Council just released a report on how to get to Mars. It considered that NASA’s plan of getting to Mars via the asteroid return mission as a stepping-stone might work. However, actually the NRC considers it a bad idea, with plans going to the Moon first being preferred:

NASA could not deliver humans to Mars, says new strategy report.
Published time: June 05, 2014 02:39
Landing humans on Mars is unattainable for NASA if the space agency’s current strategy and level of funding are not modified in the near future, according to a new congressionally-mandated report.

Of the three pathways to Mars that NRC suggested, two were associated with a return to the moon. A lunar landing and habitat would hone technologies that could later be employed on a Mars mission, the report said.
The Obama administration has publicly expressed distaste for continued, expensive moon landings. In outlining US space policy in 2010, President Barack Obama said, “I just have to say pretty bluntly here: We’ve been there before.”
The third option outlined by the report includes the Asteroid Redirect Mission, a plan still in the study phase but currently endorsed by the Obama administration.
Such a mission would send robotic spacecraft to essentially grab and re-orbit an asteroid passing near Earth, allowing astronauts to take samples of the rock.
That mission, though, is not preferred by authors of the report. Safety issues and development of “dead end” technologies render the asteroid mission inferior if NASA wants to reach Mars, it said.
The asteroid option “cannot provide the flight frequency required to maintain competence and safety,” the report posits.

http://rt.com/usa/163736-mars-nasa-funding-strategy/

In point of fact the current NASA idea of dismissing any return to the Moon is making it that much harder for us to understand how to get to Mars. The only reason for the perception we can’t return to Moon is the idea developing a manned lunar lander would be too expensive. But you need a lander anyway to land on Mars, and by developing a lunar lander you can also use that as a Mars lander. And if you break your mindset out of the box that the lunar lander has to look like the $10 billion Altair lunar lander, you grasp the lander can actually be developed at over a hundred times cheaper than that. Both the Masten XEUS lander and the NASA Morpheus lander can be made into manned landers at only a few 10's of millions of dollars in development cost.

So this self-imposed limitation on their own thinking is making it that we can’t get to Mars either.

  Bob Clark


Nanotechnology now can produce the space elevator and private orbital launchers. It now also makes possible the long desired 'flying cars'. This crowdfunding campaign is to prove it:
Nanotech: from air to space.
https://www.indiegogo.com/projects/nano … 13319568#/

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#78 2014-06-14 14:04:20

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,819
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Re: A Return to the Moon by the Apollo 11 50th Anniversary.

NASA doesn't want to go to Mars.  I thought that was obvious by now.  Why is this still a question? 

NASA does not want to send humans to Mars because (1) it is dangerous,  and (2) it is difficult.  They cannot make a big PR splash unless it is neither.  It is not.  It will still be difficult and dangerous for some time to come. 

NASA has not wanted to go to Mars with humans since Nixon's executive order in 1972 that killed all human spaceflight outside LEO.  When that order came down in the middle of the Apollo landings (planned all the way through Apollo 22,  with hardware already built !!!!),  they still had a mission on the books for humans to Mars in the 1980's,  and they were testing the NERVA engine that was to take them there. 

All of that was dead by 1974.  "Why build the rocket if we're not going to go?" was the rationale for killing everything associated with human spaceflight outside LEO.  The shuttle and the space station were "sops" to NASA to keep them busy.  Nothing more.  The "can-do" NASA of 1960 was dead by 1975.  It is still dead.  And the other countries' agencies are modeled on it.  All dead.  That's why nobody has gone. 

Although,  we learned an awful lot from both "sop" programs (shuttle and space station).  Including the fact that a human crew in a tiny space capsule for months one way to Mars would have died on that Mars mission back in the 1980's.  I repeat:  they would have died.  Even if the hardware had worked perfectly. 

It would have been a race to see what actually killed them:  (1) microgravity diseases (and I do mean plural !!!),  (2) solar flare radiation,  or (3) fatal insanity from too-tight confinement.  But,  we have known how to send a crew to Mars successfully and safely (!!!!!) since about the mid-1990's,  mostly from knowledge gained off the ISS and some Russian stations. 

We didn't send a crew to Mars,  because NASA has not wanted to go,  nor have any of the presidents since Kennedy.  Nor has congress.  The public excuse is that it's "too expensive".  But that is a convenient lie maintained by a NASA who no longer wants to go,  and by a whole swarm of space program opponents.  Strange bedfellows,  those are,  don't you think?

It is simply not too expensive anymore.  It has not been "too expensive" ever since the advent of commercial satellite launch at about $2500/pound,  added to the on-orbit assembly by docking that we did for ISS.  And that price should fall a little further (factor 2-ish or at most 3-ish) as available launcher payload sizes grow to the 100 ton class.  Just DO NOT count on SLS to price-out that low!  IT WILL NEVER BE THAT CHEAP! 

Anymore,  nobody wants to go,  except visionaries like Musk,  Branson,  and some others.  None are government employees.  The long-established contractors (Boeing and Lock-Mart) make more money on dead-end gravy-train programs than they would ever make actually building the hardware to go to Mars.  That's why THEY don't want to go, either.  Together they're ULA,  so ULA doesn't want to go. 

I think we need some new contractors.  It's way past time to break the monopolies. 

Money has always talked far louder than the law,  common sense,  or any collective societal goals we have ever had.  You all know that!  So why is this (NASA wanting-or-not to go to Mars with humans) still a question?

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#79 2014-06-14 18:44:04

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

GW Johnson wrote:

NASA doesn't want to go to Mars.  I thought that was obvious by now.  Why is this still a question?

The what are those Orion capsules for? NASA is developing capsules designed to return astronauts from interplanetary missions.

GW Johnson wrote:

NASA does not want to send humans to Mars because (1) it is dangerous,  and (2) it is difficult.  They cannot make a big PR splash unless it is neither.  It is not.  It will still be difficult and dangerous for some time to come. 

NASA has not wanted to go to Mars with humans since Nixon's executive order in 1972 that killed all human spaceflight outside LEO.  When that order came down in the middle of the Apollo landings (planned all the way through Apollo 22,  with hardware already built !!!!),  they still had a mission on the books for humans to Mars in the 1980's,  and they were testing the NERVA engine that was to take them there. 

All of that was dead by 1974.  "Why build the rocket if we're not going to go?" was the rationale for killing everything associated with human spaceflight outside LEO.  The shuttle and the space station were "sops" to NASA to keep them busy.  Nothing more.  The "can-do" NASA of 1960 was dead by 1975.  It is still dead.  And the other countries' agencies are modeled on it.  All dead.  That's why nobody has gone. 

Although,  we learned an awful lot from both "sop" programs (shuttle and space station).  Including the fact that a human crew in a tiny space capsule for months one way to Mars would have died on that Mars mission back in the 1980's.  I repeat:  they would have died.  Even if the hardware had worked perfectly. 

It would have been a race to see what actually killed them:  (1) microgravity diseases (and I do mean plural !!!),  (2) solar flare radiation,  or (3) fatal insanity from too-tight confinement.  But,  we have known how to send a crew to Mars successfully and safely (!!!!!) since about the mid-1990's,  mostly from knowledge gained off the ISS and some Russian stations. 

We didn't send a crew to Mars,  because NASA has not wanted to go,  nor have any of the presidents since Kennedy.  Nor has congress.  The public excuse is that it's "too expensive".  But that is a convenient lie maintained by a NASA who no longer wants to go,  and by a whole swarm of space program opponents.  Strange bedfellows,  those are,  don't you think?

It is simply not too expensive anymore.  It has not been "too expensive" ever since the advent of commercial satellite launch at about $2500/pound,  added to the on-orbit assembly by docking that we did for ISS.  And that price should fall a little further (factor 2-ish or at most 3-ish) as available launcher payload sizes grow to the 100 ton class.  Just DO NOT count on SLS to price-out that low!  IT WILL NEVER BE THAT CHEAP! 

Anymore,  nobody wants to go,  except visionaries like Musk,  Branson,  and some others.  None are government employees.  The long-established contractors (Boeing and Lock-Mart) make more money on dead-end gravy-train programs than they would ever make actually building the hardware to go to Mars.  That's why THEY don't want to go, either.  Together they're ULA,  so ULA doesn't want to go. 

I think we need some new contractors.  It's way past time to break the monopolies. 

Money has always talked far louder than the law,  common sense,  or any collective societal goals we have ever had.  You all know that!  So why is this (NASA wanting-or-not to go to Mars with humans) still a question?

GW

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#80 2014-06-15 14:42:21

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,819
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Re: A Return to the Moon by the Apollo 11 50th Anniversary.

I'm sorry,  but you are wrong about the Orion capsules,  Tom. 

Those will NEVER be adequate by themselves for any mission beyond cis-lunar space.  I know the PR says "interplanetary missions",  but that's a convenient lie. 

Orion is way too small for long-duration flight beyond 2 or 3 (or at most 4) weeks.  It has no radiation shielding for solar flares.  And just where are you going to store the supplies for a crew on a 2.5 year mission? Not in that ESA service module,  not by a long shot.  How will you keep the crew healthy with 2.5 years' exposure to low-to-zero gravity?  (We already know that about 450 days is the outer limit for that.) 

All of this is apparent to any casual observer.  But you do need to be aware of it,  to see it.  They are counting on you being unaware of it. 

Orion was developed only for going back to the moon,  nothing more.  Nothing about that capsule development was changed,  even when Constellation (to go back to the moon) was cancelled.  It became a gravy train for favored contractors some years ago.  I think it will eventually fly,  but only to the moon's vicinity all by itself. 

Going to Mars either requires super-fast travel (not yet possible),  or it requires a big habitat space properly arranged,  artificial gravity-by-spin,  a proper radiation shelter (20 cm water will do),  and plenty of space to store supplies.  With artificial gravity,  life support becomes a lot easier,  too (you can do free-surface cooking with water,  and simple toilets,  among many other advantages). 

A good lander is also required,  plus its propellant supply.  And,  there's the surface supplies and equipment to investigate how to live-off-the-land while the crew is there.  Why go if you're not landing?  It's so hard to get there,  what's the point of going and NOT landing?

Orion by itself has NONE of that.  NASA isn't working on ANY of that,  at least not seriously.  And THAT is why I said what I said about NASA. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#81 2014-06-15 19:46:37

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

The Orion capsules are basically to return astronauts to Earth in the context of a Mars mission, the rest of the ship is to get the astronauts to and from Mars and to land and take off from Mars. The Orion would be good for getting the astronauts to the interplanetary spaceship from Earth and from the Interplanetary spaceship to Earth. For example the mission could call for the ship to be build at the Earth-Moon L5, L4, L1, or L2 points. L4, and L5 are the same distance from the Earth as the Moon, and an Orion capsule returning from those points would face the same heat of reentry as the Apollo capsules did. I think an interplanetary vessel with ion or plasma engines could leave the vicinity from Earth using a nuclear reactor to power them, or alternatively a Cycling Spaceship could do a Flyby of Earth and an Orion would rise up from Earth to match its velocity, carrying a Mars lander with it. the Cycling spaceship is basically a space station that repeatedly visits Mars an Earth with minimal expenditure of propellant. My guess is the Mars craft would be built at one of these Lagrange points and then boosted into a Cycling orbit, serving as the habitat for the astronauts during the interplanetary leg of the mission. An optimal mission would call for two cycling spaceships, one optimized for a minimum duration outbound leg, the other for a minimum duration inbound leg. To save costs, only the outbound cycler need spin for gravity, on the inbound cycler the astronauts can be allowed to float, they'll spend several months in weightlessness as thy return to Earth and they'll recover in a hospital upon their return.

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#82 2014-06-16 20:25:27

idiom
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From: New Zealand
Registered: 2004-04-21
Posts: 312

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

This thread might equally be re-titled A return to manned spaceflight for Apollo's 50th anniversary.

Gives Space X or whoever just over 5 years to get it together.

Sure as heck Nasa couldn't put a man in space in under 5 years.

Last edited by idiom (2014-06-16 20:32:22)


Come on to the Future

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#83 2014-06-17 07:03:04

Void
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Registered: 2011-12-29
Posts: 3,021

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

For a minimum effort extraction of materials from the moon, I guess I would speculate on a robotic tricycle.  The rear two wheels have brakes, and the front wheel being a “Brush”.  Under the tricycle would be slung a dust pan.  The target would be Moon dust.  The back end could have a balancing weight which would also be useful machinery, which could control the amount of force being imposed on the front wheel / circular brush.
As dust is considered a hazard to work on the Moon, the partial removal of it from a surface area would provide a bulk material to extract to orbit, and also a cleaner surface area to later place some machines of a speculated future activity.  It would also provide scientific data, since the dust could be separated and examined in orbit, if that had some value, and the swept surface would expose rocks that could be examined robotically.
I presume the dust pan must be emptied somehow into a bin, the bin perhaps being picked up later by a hook on a lander of some sort.  I choose not to dwell on the details, because there would be many variations that might work.
The value of the materials extracted would include Oxygen, and of course a spectrum of materials.
For magnetic materials not to be used to make machines, I suggest the Mond process be employed, and the liquid be channeled into an spray paint type of device that will spray it using pressurized heated gas, and an educator.  The purpose would be to generate a fine powder with some magnetic properties.
Iron Pentacarbonyl  as a liquid, and Nickel Pentacarbonyl perhaps. 
Exposure to the atomizing hot gas should atomize the material and also convert it to tiny Carbonyl Iron/Nickel spheres.
I presume this would occur in a pressurized chamber, so as to be able to recycle the gasses.
Useful for;
Electronics
Powder Metallurgy
I am also interested in squirting it out of a mass driver as a powder mixed into a gas as a slurry.  I have questions about the actual magnetic properties of the powder, and really have some ideas for the mass driver, but no set design.  It would be nice to incorporate a introduction of a Oxidizer into the ejection process and so a dust explosive burn to add propulsion, but that could contradict or complicate the mass driver process.
Human visits necessary to the Moon to support the extraction process would have to be paid for by an actual value of it.  If that money equation proved true, then I don’t have a problem visualizing a device being built and contracted for hire by some company or national entity.
The value of ejecting fine dust might be that the solar wind, or the Earths magnetic field might act to eventually sweep the dust from the area of it’s ejection, which I suppose might be a good thing.
I also have my eye on Phobos and Demos, and also 16 Psyche (Big chunk of Iron/Nickel)
As for the energy for the propulsion device, I suppose variations.  I am not against fission nuclear.


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#84 2014-06-17 18:19:05

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,819
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Re: A Return to the Moon by the Apollo 11 50th Anniversary.

Tom made my point with his statement "The Orion capsules are basically to return astronauts to Earth in the context of a Mars mission, the rest of the ship is to get the astronauts to and from Mars and to land and take off from Mars."  He and I are saying the same thing about NASA and its Orion capsule,  he just didn't think so when that issue first came up. 

As for a "cycler", how is that different to any significant degree from using an orbit-to-orbit transport coupled with landers at destination and a return capsule at LEO? 

I'll answer my own question:  if you go orbit-to-orbit,  you are less restricted in your choice of return date.  It becomes only a matter of shipped propellant supply,  or what you can make in-situ at Mars,  or both.   

So,  I see little point to leaving hardware in the transfer orbit as a cycler,  instead of parking it directly in the orbit about the destination. 

You have to make those burns anyway, and with the majority of the mass,  unless you attempt to build far-too-massive a cycler.  Which would be too expensive.  So,  what's the point of the cycler,  vs the orbit-to-orbit transport?

I'm coming around to the notion of having both conventional and electric engines on the manned orbit-to-orbit transport.  I'd use the conventional engines for impulsive departures and arrivals to orbits,  thus eliminating months of spiraling in and out with electric propulsion.  Time is money you know,  even for unmanned vehicles.  But with men,  low travel times are even more crucially important for interplanetary missions. 

The electric propulsion I would use during the manned transfers,  to cut down the time on the transfer trajectory between departure and arrival orbits by means of a higher mid-point velocity.  However much solar electricity you can actually make,  that's how much extra impulse you can add to the transfer trip.  It's a win-win,  no matter how crummy the electric propulsion thrust/weight is.  And they are crummy.  All of them. 

My own choice would be LH2-LOX conventional,  with an oxygen-based electric.  The conventional uses LOX/LH2 at 6:1,  with those being produced at 8:1 from water by solar-electric electrolysis and liquefaction.  The excess O2 gets used for life support and the electric propulsion propellant.  Propellant for "immediate use" is stored as cryogenic LOX and LH2.  The rest gets shipped as super-easy-to-store water,  and gets converted as needed "on the way". 

There is water-as-ice all over Mars.  In some few places the deposits are massive,  and therefore easy-to-mine,  which tells you where you really want to land.  If you use the same LOX-LH2-from-water for your reusable (many multiple flights) lander as for your orbit-to-orbit transport,  then in-situ propellant manufacture is more of a "sure thing",  and will support additional suborbital missions using those landers.  Cleaning local dirty water is easy:  just filtering and gravitational separation of solids,  and the local salt content just makes it more conductive for the electrolysis.  The waste product is concentrated,  dirty brine.  So what?

All of this leads pretty quickly to the same overall mission design.  It ain't minimalist.  So why is there still debate about this?

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#85 2014-06-17 21:42:45

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

GW Johnson wrote:

Tom made my point with his statement "The Orion capsules are basically to return astronauts to Earth in the context of a Mars mission, the rest of the ship is to get the astronauts to and from Mars and to land and take off from Mars."  He and I are saying the same thing about NASA and its Orion capsule,  he just didn't think so when that issue first came up. 

As for a "cycler", how is that different to any significant degree from using an orbit-to-orbit transport coupled with landers at destination and a return capsule at LEO?

 
A cycler is a space station in a very particular elliptical orbit around the Sun, an orbit who's period is an interger multiple or the orbits of both Earth and Mars, that is when it is in one part of its orbit, it is near Earth, and when it is in another part of its orbit, its near Mars.
To give an example Earth has an orbital period of 365 days, Mars has an orbital period of 687 days
You can have an orbit that with a period of 15 year years and approximately 8 Mars years with a 99.62% correspondence, a little reaction mass will have t be expended to adjust for the fact that the orbit period of 15 Earth orbits doesn't quite match 8 Mars orbits but is it rather close. An orbit with a semimajor axis of 6.085 au with the nearest point at 1 au and a farthest point of 11.17 au will have an orbit period of about 15 years, each time it is closest to the Sun, the Earth will be nearby, the rocket carrying the astronauts will simply have to match the velocity of the Cycler as it passes close to Earth. Another cycling orbit will have a reciprocal relationship to the first in that it will first pass closely to Mars and then go to Earth whereas the first one passed closely to Earth then when to Mars.

A Cycler is a space station, it is potentially no different from the International Station other than its orbit and location. An orbit to orbit spaceship is a space ship, if it is reusable and not the throwaway kind then its engines will have to be used multiple times and refueled, A Cycler will uses its engines less and mostly during its initial acceleration to put it in its cycling orbit. An orbit to orbit spaceship uses fuel faster and its engines will wear out faster because they'll get used with each mission, a Cycler is just a space station and you can make them as large as you want, you could even use an O'Neill colony as a Cycler if you want, though that's in the far future. An Island One or Stanford Torus can transport 10,000 colonists to Mars in comfort, some might even choose to live on the Cycler rather than go to Mars.

GW Johnson wrote:

I'll answer my own question:  if you go orbit-to-orbit,  you are less restricted in your choice of return date.  It becomes only a matter of shipped propellant supply,  or what you can make in-situ at Mars,  or both.

   
Engines also need maintenance if the are reused, you just can't keep on firing them and firing them over and over again with each mission without eventually having to take the ship to a repair facility and replace some old parts, its not just fuel, and repairing a spaceship is an expensive thing to do in space. if the Cycler space station stays in the same orbit all the time, it doesn't use its engines much, and so it needs less repair of maintenance, most of that have to do with maintaining the environment within the space station and restocking the consumables such as food, oxygen and water for instance. Most of the mass of the Cycler is accelerated only once.

GW Johnson wrote:

So,  I see little point to leaving hardware in the transfer orbit as a cycler,  instead of parking it directly in the orbit about the destination. 

You have to make those burns anyway, and with the majority of the mass,  unless you attempt to build far-too-massive a cycler.  Which would be too expensive.  So,  what's the point of the cycler,  vs the orbit-to-orbit transport?

A more massive cycler will allow you to transport more people at once, and you can pack the passengers into the launch rockets airline style rather than giving them each a room to sleep. Living quartes for the launch rocket could be just a seat, the trip from Earth to the Cycler will be short anyway, most of the equipment needed on the Mission will be launched separately and not with the astronauts, and they need not be launched with man-rated rockets, they could use ion drives to accelerate and meet up with the Cycler while the astronauts will require chemical rockets that are less efficient and therefore more expensive. I think the Cycler could even use a Solar Sail to maintain its orbit.

GW Johnson wrote:

I'm coming around to the notion of having both conventional and electric engines on the manned orbit-to-orbit transport.  I'd use the conventional engines for impulsive departures and arrivals to orbits,  thus eliminating months of spiraling in and out with electric propulsion.  Time is money you know,  even for unmanned vehicles.  But with men,  low travel times are even more crucially important for interplanetary missions. 

The electric propulsion I would use during the manned transfers,  to cut down the time on the transfer trajectory between departure and arrival orbits by means of a higher mid-point velocity.  However much solar electricity you can actually make,  that's how much extra impulse you can add to the transfer trip.  It's a win-win,  no matter how crummy the electric propulsion thrust/weight is.  And they are crummy.  All of them. 

My own choice would be LH2-LOX conventional,  with an oxygen-based electric.  The conventional uses LOX/LH2 at 6:1,  with those being produced at 8:1 from water by solar-electric electrolysis and liquefaction.  The excess O2 gets used for life support and the electric propulsion propellant.  Propellant for "immediate use" is stored as cryogenic LOX and LH2.  The rest gets shipped as super-easy-to-store water,  and gets converted as needed "on the way". 

There is water-as-ice all over Mars.  In some few places the deposits are massive,  and therefore easy-to-mine,  which tells you where you really want to land.  If you use the same LOX-LH2-from-water for your reusable (many multiple flights) lander as for your orbit-to-orbit transport,  then in-situ propellant manufacture is more of a "sure thing",  and will support additional suborbital missions using those landers.  Cleaning local dirty water is easy:  just filtering and gravitational separation of solids,  and the local salt content just makes it more conductive for the electrolysis.  The waste product is concentrated,  dirty brine.  So what?

All of this leads pretty quickly to the same overall mission design.  It ain't minimalist.  So why is there still debate about this?

GW

Last edited by Tom Kalbfus (2014-06-17 22:14:49)

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#86 2014-06-19 13:43:17

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,819
Website

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

A cycler with an orbital period of 15 earth years means either (1) you only have travel opportunities every 15 years,  or (2) you must have several of these vehicles out there,  each in its own orbit with a 15 year period,  just a different position along that orbit.  For an equivalent every-opposition travel opportunity,  you would have to have 7 or 8 cyclers out there,  since oppositions occur roughly every 2 years.  The actual possibilities are a digitized spectrum between those extremes,  digitized by the number of cyclers actually deployed. 

Such a cycler vehicle is at least ballpark-equivalent to building a more conventional orbit-to-orbit transport vehicle.  We're talking about stuff assembled into a space station-like structure out of smaller components assembled together by docking.  The effort and cost for the cycler could be a lot more,  depending upon just how big a cycler you go for.  But as a minimum,  it ought to be comparable in size to the reusable transport ship. 

If you opt for choice (2) and also opt for a minimum cycler size,  then building 1 cycler would crudely cost about the same as building 1 reusable transport,  building 6 cyclers would be 6 times as expensive as building 1 reusable transport,  etc.  Now,  the transport might indeed have higher maintenance and refurbishment costs,  which would reduce the contrast of the up front construction cost ratio some.  But for more than 1 cycler,  it's still factors > 1 , perhaps >> 1,  never < 1. 

So,  assuming 15 years between trips is OK, costs are crudely comparable if you build only one cycler,  but only with it further restricted to be of a size comparable in effort and outlay to your transport ship.  If you build anything bigger for your cycler,  the reusable transport is always the better deal financially.  Remember,  each would use "fairly comparable" infrastructure to effect flights up from Earth and the flights down to Mars.  And return.

I say "fairly comparable",  the infrastructure for the cycler is actually 40+% more demanding:  escape versus orbit plus a tad more to reach the cycler transfer orbit,  at each end of the journey.  In contrast,  the reusable orbit-to-orbit transport leaves from LEO,  and parks in LMO,  for minimal delta-vee demands on the infrastructure.  What you save in Earth and Mars infrastructure costs with the orbit transport pays for the higher delta-vee demanded of the orbit-to-orbit transport.  You'll pay that cost the same,  one way or the other,  anyway. 

If 15 year travel opportunities are unacceptable,  then you must have multiple cyclers out there,  each of which is an investment comparable to (or more than) that of the reusable transport.  There is no way around that dilemma,  it must be faced immediately,  up front,  when you start the competing designs.  In that case,  the reusable transport is always the far-better deal financially,  plus it has travel opportunities each-and-every opposition,  which is roughly every 2 years.  It takes 7 or 8 cyclers to match that,  as I said before. 

Bottom line:  the cycler approach can never cost less-to-build than the reusable transport approach,  but could cost many-factors-more to build,  if multiple cyclers are required,  or if very large cyclers are desired.  Life cycle cost ratios are probably similar in direction but less contrasting in magnitude.

So,  that explanation taken all together is why I think constructing a conventional but reusable orbit-to-orbit transport makes very much more common sense than constructing and riding a system of cyclers. 

GW

Last edited by GW Johnson (2014-06-19 13:55:52)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#87 2014-06-19 15:00:35

Tom Kalbfus
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Posts: 4,401

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

You could do shorter cycler periods, but you would need more maneuvering to adjust the orbit each time. The orbit period of Earth is 365 days, the orbit period of Mars is 687., and an Earth year goes into a Mars year 1.8809 times. It would be a lot better if Mars had an orbital period that was exactly twice that of Earth. So you could have a powered cycler that bends the orbit each time or you could use Earth's gravity to bend the orbit towards Mars. My calculations did not assume any planetary gravitational assist. Otherwise you can have 15 Earth orbits for every 8 Mars orbits. One could have the Cyclers do other things when they aren't being used to do direct planet to planet transfers.

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#88 2014-06-19 15:36:32

Terraformer
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From: Lancashire
Registered: 2007-08-27
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Re: A Return to the Moon by the Apollo 11 50th Anniversary.

You could, perhaps, have space colonies on cycling orbits, trading with both planets every time an opportunity comes?


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#89 2014-06-21 05:53:38

Tom Kalbfus
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Re: A Return to the Moon by the Apollo 11 50th Anniversary.

I think this could be used for a quick return to the Moon by the next President, that would be the easiest thing to do with the Orion.

December Test Flight Huge for NASA's Next Manned Spacecraft

.

SPACE.com
By by Mike Wall, Senior Writer
June 20, 2014 7:20 AM
Orion-launch-abort-system-617x416.jpg
The first flight test of NASA's new manned spacecraft may be six months away, but agency engineers are already looking forward to what they will learn from the trial.

NASA's Orion capsule, which is designed to take astronauts to Mars and other farflung destinations, will blast into space for the first time in December. During the unmanned mission, known as Exploration Flight Test-1 (EFT-1), Orion will travel 3,600 miles (5,790 kilometers) from Earth, then come rocketing back into the planet's atmosphere at 20,000 mph (32,187 km/h).

The December trial is a vital proving ground, since NASA plans just one more flight test (in 2017) before the capsule's first crewed mission lifts off in 2021. [Photos: NASA's Orion Space Capsule EFT-1 Test Flight in Pictures]

For example, EFT-1 will test out Orion's launch-abort system (LAS), which is designed to steer crewmembers to safety in the event of a problem during liftoff. Even if the launch goes flawlessly, however, a motor has to fire to jettison the LAS, which would otherwise block Orion's parachutes, making a soft ocean splashdown impossible.

So engineers will watch for the successful separation of the LAS during EFT-1 — the first of 17 such jettisons that must happen in sequence for the mission to succeed, officials said.

EFT-1 will also put Orion's heat shield — at 16.5 feet (5 meters) wide, the largest such structure ever built — to the test.

Orion_parachute_test.jpg

"The reason that Orion is traveling so far and coming back in so fast is to give the heat shield a good workout — the idea is to get as close as possible to the temperatures Orion would experience during a return from Mars," NASA officials wrote in an update Thursday (June 18).

"At the speed it will be traveling, the temperature should reach almost 4,000 degrees Fahrenheit [2,200 degrees Celsius]," they added. "At that same temperature, a nuclear reactor would melt down."

Parachute performance will also be key. While Earth's thick atmosphere will play the primary role in slowing the Orion capsule down, its parachutes — three main chutes and two drogues — need to finish the job. Orion must hit the water at just 20 mph (32 km/h) to make a safe splashdown, NASA officials said.

EFT-1 will also test how Orion's advanced computer system handles extreme temperatures, the rigors of launch and re-entry and high radiation levels, officials said.

Radiation exposure is a big concern for manned missions to deep space, which will take astronauts far beyond the protective cocoon of Earth's atmosphere and magnetic field. EFT-1 will spend a lot of time in the Van Allen radiation belts that surround our planet, allowing researchers to see how Orion's radiation shielding holds up.

"Sensors will record the peak radiation seen during the flight, as well as radiation levels throughout the flight, which can be mapped back to geographic hot spots," NASA officials wrote.

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.

Last edited by Tom Kalbfus (2014-06-21 05:57:06)

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#90 2014-06-21 10:56:31

Void
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Posts: 3,021

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

You are talking Mars, and cyclers, and an electric/chemical mix, so;

I notice that a constraint is imposed by the orbital relationship of Mars and Earth, requiring a rigid timing for the launch of missions.

Cyclers have a birth and a death by default.  Maybe as a habitat the death can be put off with repairs, but here the concern is the support of a mission to Mars, so not a long term habitat.

I think that things could be improved by making a cycler which is primarily electric driven, which would also use gravitational assists by interacting with Earth.  The cycler would start out as electric-unpersoned, and would evolve into a partially gravity encounter driven device.

It would be comprised of primary electrical capabilities, solar or nuclear, and an electric drive, and also a low level synthetic gravity (Specific to a human habitat part) device.  In addition it would provide refueling for a personed associated mission, and such redundancy failsafes as might be added for a mission to Mars.

I have wondered how fast a person would deteriorate if in the gravity field of Ceres.  Supposing that Mars was achieved in a A to B fashion, supporting the further expansion of humans into space, the exploration of this question has value.

I suggest that the pseudo-cycler could have a baton type rotor habitat suitable to generate a simulation of Ceres, and answer that question, while the mission was occurring.

So the aspect of human deterioration I would hope to study and perhaps modify with this process would be the fluid pooling in the upper body, which makes humans uncomfortable and also damages some things perhaps like the eyes.

A human perhaps lies down for 1/3 of the day in a bed, and yet is not damaged by that.  So, the body must be able to temporarily compensate for the loss of standing up in a gravitational field, for a significant part of the day.  Further, most people must only be on their feet for a minority part of the day.

Further, I am hoping that for the fluid pooling problem, the effects are not a strait line.  That even a small gravity field might allow the body to adjust fluid pooling in the gravitation of Ceres.  If not, then at least it is further learned that the problem is larger.

For the pseudo cycler, the tank/habitat could be an holding tank for a "Fuel" for the electric rocket.  When it was empty it could be modified to be a habitat. Needed equipment brought into the habitat from places outside where they had been stored.

When this apparatus is primed to the proper orbit by gravitational assists, Then the human mission would begin.  I suggest redundant spacecraft, two capsules capable of atmospheric return of some type.  A intercept of the cycling device by that human mission with some thought on how to abort back to Earth if possible in the event of a system failure.



The cycler having developed a elliptical orbit from electrical and gravitational processes would be primed for the mission.  As the high point of the orbit could be anywhere, this then modifies the limits of the present situation where alignments of Mars and Earth restrict the timing of missions.

The primary human capsule being specifically crafted to land on Mars and perform the Mars mission, the secondary being crafted to encounter one or two of the moons of Mars, but also being crafted to do an emergency rescue of persons on the surface of Mars in the event that was called for.

Should the human mission successfully merge with the cycler, then a automatic return abort would be in place.  However to reach Mars, if all systems were good, then a propulsive alteration of orbit would be implemented, and the game would be on.  Propulsion should stop some time before encountering Mars, so that the two atmospheric entry devices could be separated from the main craft to be allowed to spin on tethers, to provide a greater synthetic gravitation, to prepare the humans for action on the ground at Mars.  However the separation from the main craft and this synthetic gravitational device would be only enough to avoid collisions.

Prior to the encounter and capture into the gravitational field of Mars, the hardware would be secured together again, and whatever propulsion could accomplish the capture would be put into process.

At Mars, whatever pre-positioned supplies/devices would be have been put into place in orbit and on the ground as might be useful to support the objectives.

Methods to return to Earth to finish the mission would be open to best options, so I choose not to specify on that.

Returning to the cruse phase where the humans might be experimenting with a low gravitational simulation, (Ceres), I suggest that as a supplement humans might try to sleep standing up in the synthetic gravitation, with a harness.  Perhaps it is possible.  Also, I also suggest a upper body frame/harness, and a lower body frame/harness which would be actuated against each other to both compress the Legs/spine and tension them in suitable fashion to stimulate the bones.  I suggest that if there is going to be a private mission using a free return they consider trying this method to help reduce the rate of bone loss.

As for radiation protection, the pseudo cycler might be able to afford that, so while in cruse phase the humans would have significant protection.

Obviously exercise would be utilized where possible to reduce musel deterioration.  I also suggest that the electrical stimulation of mussels be investigated, such as is being used to try to help persons who cannot walk without it.  This could also have value for the bones.

I'm done.

Last edited by Void (2014-06-21 19:21:45)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#91 2014-06-22 06:39:49

Tom Kalbfus
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Posts: 4,401

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

Would you rather live in a spinning habitat or have electrical current running through your body? The human body was designed for a 1 g environment, it was not designed to be an electrical conductor, I'm not sure that would be a good idea.

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#92 2014-06-22 07:54:02

Void
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Registered: 2011-12-29
Posts: 3,021

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

Would you like to be able to afford the mission or be unrealistic?


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#93 2014-06-22 10:06:10

Void
Member
Registered: 2011-12-29
Posts: 3,021

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

What I think is the idea can be explored.

Step 1 would be to do bed tests, where a bed is tilted with feet at a lower elevation.  To test the blood pooling issue.  The other aspects could be tested.

Step 2 If it seem possible that a synthetic gravity similar to Ceres helps to prolong heath (Along with the compression/tension device, and electric stimulation/Exercise), then I speculate that a new space station that can also be used as a pseudo cycler, could be built in Earth orbit.  It would include a structure suitable for deep space travel, and a power plant, synthetic gravity/fuel tank, and a frame that supplies and equipment could be attached to.

* If my understanding is correct, then the international space station will become obsolete, and the Russians take some parts from it.  I suggest that to construct the new space station/cycler, it would not hurt to take a look at the possible reuse of some components to construct the new space station.  In addition I believe there may be a device already constructed on the surface of the Earth to test synthetic gravity, which was not deployed?

Step 3 would be to test the new station/cycler, and also confirm the utility of the treatments to reduce the rate and magnitude of deterioration of humans.

At that point it could be confirmed that that device could be incorporated into a Mars mission.

Would it ever be an Earth space station again?  Maybe it would be stationed in association with the Moon after the Mars mission.  So perhaps it's construction might have an eye on that.

So I am looking at making it pay.  The cost would serve 3 missions.  A space station to be the successor of the existing one, perhaps smaller,  A one time Mars mission, and finally a space station in L1, L2, L3, L4, or L5, to support access to the Moon for international/Business oriented activities.

In that role, perhaps a small human crew on the station would use remotely controlled robotics to work with the Moon, with occasional human visits to the Moon if necessary.

I presume that the humans returning from Mars would abandon it to a solar orbit, and re-enter the Earths atmosphere with heat shields.  So to get it from a solar orbit to a L# orbit, a robotic mission might be employed that would go get it and reposition it to a L# location.

Last edited by Void (2014-06-22 10:15:24)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#94 2014-06-22 10:58:27

Void
Member
Registered: 2011-12-29
Posts: 3,021

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

Alright, I  guess I will set your site free from me.  Good luck.  I'm going to try to stay away, but maybe not permanent.  I hope you get it back to what it was.

Last edited by Void (2014-06-23 08:27:23)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#95 2014-06-22 16:30:03

Terraformer
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From: Lancashire
Registered: 2007-08-27
Posts: 3,225
Website

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

You mean, a site discussion space colonisation, rather than earth colonialism?

I posted a thread about radiation in life support, and no-one responded.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#96 2014-06-22 18:22:18

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

No one's talking about Earth Colonialism here Terraformer, but I for one would not like to have an electrical current running through my body. I don't twitchy muscles, and I don't know the long term health problems it may cause, such as brain damage for instance, I'd rather rely on good old tried and true centrifugal force than have my muscles twitch in zero gravity through electrical stimulation. If they don't do that in Health Clubs, I wouldn't want to do that in space!
I believe they had some centrifugal force in one of the Gemini Missions involving none other than Neil Armstrong.

Last edited by Tom Kalbfus (2014-06-22 18:24:22)

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#97 2014-06-23 08:47:07

Void
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Registered: 2011-12-29
Posts: 3,021

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

Terraformer.  My intentions are good.  From time to time I do mess with you, but it should not be seen as malicious intent.

Tom,  I used a "Abb Energizer" some time back before I joined a gym.  It had problems, if you don't apply the conductive goo correctly, you can burn little holes in your skin.  However well trained persons with time on their hands (In a spaceship sometimes you would have time on your hands).  It did help.  But I got brain damage and started posting on New Mars. sad  It must be FDA approved.

Whats your story?

Taraformer.  I also encounter situations where their is no response, and I have to attribute that to the possiblity that my posts are no good.  In that case I should stop.

Again a different situation is just like the above.  Most of the people here want to paint the interior of the house before they consult an archetect, lay the foundations, put up the frame and put in the wiring and drywall.  I attribute it to a precision and accuracy oriented skill set.  Being a master of what is.  But to find a new way, you have to be careful what you dismiss without due consideration.  It is typical that things proposed are not discussed properly because it's not "tried and true".

Some people display skill by being able to play existing music with precision and style that is known to please.  Some people express skill by being inventive/creative.  To do that, you don't have a yes/no response.  (And I am not criticising you Taraformer).  In order to create a new pattern, you must draw from the library of experience.  Here I do have experience in electrical stimulation, but the response is not "I have concerns about that what are the medical implications?" or "What value can that add to a mission?"

Instead it is a false claim that centrifugal synthetic gravity has been tested in microgravity, and that it is without medical problems.  Now I think it will probably work, but I notice that there are no test devices in orbit.  It is hard to test it on Earth.

My notion of suggesting it was that it could be tested on Earth, and it might be a cost effective way to reduce the deterioration of humans on missions in space.

Further I notice that their is no comentary on several notions I proposed:
Sleeping standing up in a ~Ceres level gravitational field in a harness.
A two part frame to stress the main bone system.
Creating a carrier ship that can double as a space station successor to the one we have now, and might be used for 3 purposes useful to space efforts conserving $$$.

Yes/No decisions on inovation early in the game is no way to process an idea.

The level of utility here on this site, utility to learn and understand is substandard in many cases, and it is hard for me to justify investing my time and efforts.

Did you know that I mentioned that I had a new space suit scheme, and not one person inquired as to what that was.

So, I am taking a break of unknown length.

I have too many other things to do that matter to me at this time, and I don't see a satisfactory return on my investment, or I actually am a goofus that is getting in the way.  Either way, my time is wasted.

I have enjoyed corresponding with many of you.

Last edited by Void (2014-06-23 08:49:58)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#98 2014-07-19 09:39:59

RGClark
Member
From: Philadelphia, PA
Registered: 2006-07-05
Posts: 501
Website

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

Nice article that argues we should use the commercial space approach to
accomplish beyond low Earth orbit (BEO) spaceflight:

Apollo program a flameout at 45: Column
Rand Simberg 12:56 p.m. EDT July 18, 2014
http://www.usatoday.com/story/opinion/2 … /12734813/

Remarkably there could be profitable opportunities in BEO spaceflight that
would make it worthwhile for space companies to invest their own funds in
developing BEO spacecraft:

The Commercial Space Approach to Beyond Low Earth Orbit Spaceflight.
http://exoscientist.blogspot.com/2014/0 … -moon.html


   Bob Clark


Nanotechnology now can produce the space elevator and private orbital launchers. It now also makes possible the long desired 'flying cars'. This crowdfunding campaign is to prove it:
Nanotech: from air to space.
https://www.indiegogo.com/projects/nano … 13319568#/

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#99 2015-07-06 07:31:13

RGClark
Member
From: Philadelphia, PA
Registered: 2006-07-05
Posts: 501
Website

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

RGClark wrote:

A recent report suggests using the hydrogen tank of an upper stage for the SLS as a space station:

Skylab II: A NASA 'Back to the Future' Concept to Open Up Space Exploration
By Mark Whittington | Yahoo! Contributor Network – Fri, Dec 21, 2012
http://news.yahoo.com/skylab-ii-nasa-ba … 00842.html

(expired link. Try this instead:

NASA Mega-Rocket Could Lead to Skylab 2 Deep Space Station.
"Living beyond the moon
Griffin and his colleagues envision placing Skylab II at the Earth-moon Lagrange point 2, a gravitationally stable location beyond the moon's far side.
Over the past year or so, NASA has been drawing up plans for a possible manned outpost at EM-L2. A station there would establish a human presence in deep space, serve as a staging ground for lunar operations and help build momentum for exploring more distant destinations, such as asteroids and Mars, advocates say.
The Skylab II concept could also help ferry astronauts to these far-flung locales, Griffin said."
by Mike Wall, Space.com Senior Writer   |   April 02, 2013 07:30am ET
http://www.space.com/20444-nasa-deep-sp … ylab2.html )

Note there had been suggestions before of using the space shuttle external tank(ET) as a space station:

The Space Island Project
http://www.youtube.com/watch?v=sYIo-0qo9FA

STS External Tank Station
www.astronautix.com/craft/stsation.htm

The External Tank Torus.
A Technical Review by David Buth
http://freemars.org/studies/torus/ettoru2.html

Using the External Tank From the Space Shuttle as a Space Station ...
aeromaster.tripod.com/grp.htm

At an empty tank mass of 26.5 metric tons(mT) this would be well within the
capability of the 70 mT SLS of getting this to LEO, as at least an outer hull
of a space station. Note for this purpose we could remove the ET bulkheads so
it would even weigh less than this.
This would have a two and a half times the volume of the ISS.
And at the 130 mT payload capacity of the later SLS version, using Centaur
style in-space stages we could even transport this to the Moon.

That "Skylab II" idea was for using just the hydrogen tank only of a proposed upper stage for the SLS. But the entire tank for the SLS core, 50% large than the shuttle ET, will have an approx. 3,000 cubic meter volume. This is over 3 times the pressurized volume of the ISS and over 6 times that of the ISS habitable volume:

International Space Station: By the Numbers.
by Remy Melina   |   August 03, 2010 04:49pm ET
"1.5: The number of 747s that would provide the equivalent volume of space that is pressurized within the ISS, allowing the crew to work without spacesuits.  Of the 33,023 cubic feet (935 cubic meters) of pressurized volume, about 15,000 (425 cubic meters) is habitable volume where astronauts can live ? more room than a conventional three-bedroom house."
http://www.space.com/8876-international … mbers.html

Note that the 70 metric ton payload capacity of the Block 1 SLS was without an upper stage. So the core plus 70 mT payload would make it to orbit.  So it could be used as a space station or as a propellant depot in LEO.

But that "Skylab II" proposal was as a station at L2. The problem would be getting the core stage's 85 metric dry mass to L2. With the 70 mT payload capacity to L2 likely a SEP stage could take the core to L2 considering the lowered mass needed for solar electric propulsion. Once there it could also be used as a propellant depot.

It would seem that the SLS itself could be used to place it at L2 if refueled in LEO. Note it would only need a fraction of the ca. 1,000 mT propellant load of the SLS for the purpose, perhaps only about 100 mT. Unfortunately the SSME's are not restartable. They are reusable but they require significant refurbishing before they are fired again.

I have discussed before that with large chemical rocket stages placed at L2, such as the SLS core, that they could be used to cut the transit times to weeks instead of months just using chemical propulsion alone. The problem with using the SLS core for the purpose is that the SSME's are not restartable without refurbishment. It may be possible if there is a station already set up at L2 then the required refurbishment could be done there.

  Bob Clark


Nanotechnology now can produce the space elevator and private orbital launchers. It now also makes possible the long desired 'flying cars'. This crowdfunding campaign is to prove it:
Nanotech: from air to space.
https://www.indiegogo.com/projects/nano … 13319568#/

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#100 2019-01-04 22:37:42

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 18,301

Re: A Return to the Moon by the Apollo 11 50th Anniversary.

It i sad that Nasa can not even do a moon mission with SLS even in its most powerfull form as they have lost the engineering edge and are looking to do a refueling wey station to allow them to do one with 2 rocket launches.

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