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#1 2006-06-05 19:32:36

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: gaetanomarano Lunar Space Station

I think that a reusable-LSAM may give great advantages (for astronauts' safety and moon exploration) if joined with some Crew Habitats on the Moon and a Lunar Space Station www.gaetanomarano.it/articles/009_LSS.html

Yes one the key advantages of a reusable LSAM that went from LEO to the lunar surface and back would be safety, it would eliminate the risks of LOR operations and multiple engines. RTTM includes the idea of an outpost base to enable extended stays of six months. A very useful Mars analog station to help understand low gravity adaptation as well as providing extensive exploration facilities.

What would be the purpose of a Lunar space station? this would be incredibly expensive.

...What would be the purpose of a Lunar space station? this would be incredibly expensive...

the main reason for a Lunar Space Station (and some Crew Habitats on the moon) is to "SAVE the Astronauts' LIFE" (like I write in my article from the title)

all missions' architecture without a LSS and some CH need that ALL work well, since they have not a "B" plan (no matter how much efficient they are)

the cost of a LSS with two modules is not too high, since it can be built with the same ISS' technologies and factories

however, it may save the astronauts' life if something goes wrong (and the human life is priceless)

A lunar space station is a terrible idea, and offers no safety bennefits

If you are on the Moon and something goes wrong, you would have to launch off the surface and to the waiting stations in Lunar orbit: this involves the proper function of the main engine, the proper function of the guidence system, the proper function of the docking system, and the proper function of life support during this operation to reach a hypothetical Lunar space station. And if you can do all that, then chances are there isn't a problem, at least not one you need a space station, life support is very likly the last thing that will go wrong, especially since it doesn't have to do anything really riggerous like a rocket engine.

If the ~$1.0-1.5Bn price tag of each of the American modules on the ISS is any indicator, it would cost in the region of $3.0-4.0Bn if you add power, cooling, and stationkeeping ability. Then you would need the rockets to send the thing, which would run you in the region of $1.5-2.0Bn (about 3-4 CaLVs I bet), in part for the heavy-duty radiation shielding and LOC fuel. Add another $1.5Bn for 25% margin and you are talking around $8.0Bn for the space station.

...With the CEV in orbit offers you exactly the same safety option, expect if your orbital allignment or docking guidence system isn't perfect the CEV would be maneuverable enough to match orbits and pick you up. And if you have sick/wounded astronauts, you could light up the TEI burn and return to Earth directly and immediatly.

Even better, the CEV will be "fresh" from Earth less then six months ago, while the Lunar space station will be years old and becomming decrepit like Mir, especially thanks to the lack of manned maintenance.

Also, Lunar orbit is not 100% stable like Earth orbit, and so the station would require occasional orbital reboosting or adjustment. The station will however, unlike the CEV, have to do this when there are astronauts on the Moon or not, which will prove expensive given that it will weigh far more than CEV and importing fuel is difficult.

Edit: My precience tells me that you will soon jump up and down with bold red letters and exclamation marks about the possibility of solar flares.

This is easy to address:

  • -For short term exploration missions, the chances of a solar flare are small for the two-week trip
    -For long term base missions, the Lunar base will have a radiation shelter in which case they won't need to flee to a space station.
    -The CEV's electronics won't be any more vunerable to solar flares then the space station will, unless the latter has an absurd amount of shielding
    -Acending to the station before a solar flare would hit would be unlikely anyway, better to hide behind a boulder and wait it out

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#2 2006-06-05 19:36:40

SpaceNut
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Re: gaetanomarano Lunar Space Station

I could see how when reviewing how the Apollo program when Nasa did there lunar exploration and leaving the capsule command module in orbit with a single astronaut onboard could be viewed this way.

As pointed out it is of limited value for safe haven or for rescue and is very condition for use oriented.

But ultimately what does a station orbiting around the moon do for the transistion from exploration to colonization, that is what is important.

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#3 2006-06-05 21:03:58

GCNRevenger
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Re: gaetanomarano Lunar Space Station

Some more thoughts...

-If the LSAM life support or power system fails, then getting up to the CEV for a ride home is just as good as a station.

-If the CEV fails during transit to the Moon, it will still have the LSAM docked to it for backup power/life support Apollo-XIII style.

-If the CEV fails during transit from the Moon, then you can't reach the station.

-If the LSAM acent can't reach the CEV, it can't reach the station either.

...The only concieveable situation I can think of where the station would present a real safety bennefit is after the LSAM acends to orbit but the CEV is non-functional, which would leave you in trouble.

However, the CEV will have been launched prior to departure from Earth orbit, which will leave you ample time to test it before setting off for the Moon, particularly the engine which will have to fire at least once to circularize the orbit, so we will already know that particular engine does work.

For short-term missions, because the CEV will be "fresh," this will simply not be a big risk. The capsule will have been checked within two weeks. For long-term base missions, the solution is to simply depart on the CEV that the replacement crew rode on, which will likewise be fresh.

Even if not, Soyuz can be stored on orbit for six months without a single failure after 100 missions, then CEV can too.

As opposed to a space station thats been sitting in orbit for years, soaking up solar flares, and burning gobs of fuel to maintain its unstable orbit. A CEV that doesn't stay in Lunar orbit long won't have to burn much if any fuel for that purpose.

Oh, speaking of engines, if you are going to spend any length of time on the Lunar station waiting for a rescue mission, then you are going to have to rely on its stationkeeping engine to reboost your orbit, right? Well, which engine would you prefer to rely on? One thats less then six months old (probably only a week old) on the CEV and was test fired once, or rely on an engine thats been sitting in Lunar orbit for years with the vast number of hot/cold cycles and solar radiation/flares. The supposedly super-reliable engines on the Russian ISS module failed a recent test-firing.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#4 2006-06-06 03:50:34

gaetanomarano
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Re: gaetanomarano Lunar Space Station

...lunar space station is a terrible idea, and offers no safety bennefits...

ESAS moon missions' architecture is very close to Apollo and only a few details changes

the CEV/LSAM duo is reaching the moon, the LSAM must brake it for LOI but its engines (or electronics or another system) don't work

the LSAM must be jettisoned and (without the LSAM weight) the CEV can perform the LOI with its engine... but, after, the CEV can't come back to earth... the Apollo CSM was built with fuel for (both) LOI (with the LM) and TEI... the CEV/SM will have ONLY the fuel for TEI and "a few lunar orbit change/adjust"

with the LSS, the CEV can use the last fuel to reach it and have 6+ months of time to wait for a rescue or another CEV launched from earth without crew or (simply) for a SM refuel (if the SM will be designed for that)

without the LSS the astronauts will have a few days of life support and will DIE

in the Apollo-style mission, if the LSAM ascent engine don't works the astronauts will DIE within a few days

with one-two Crew Habitats (simply a pressurized landing-only LSAM with its 20 tons payload used only for 6+ months life support and sent with one CaLV launch) the astronauts can wait a new LSAM or more life support re-supply

with the LSS (and 2+ reusable LSAM docked to it) they can fly with a second LSAM (landed remote-controlled) within HOURS

in the Apollo-style mission, the ascent LSAM module may not reach the CEV orbit... the CEV can change its orbit to dock the LSAM module (that will have a few hours of life support) but it can come back to earth only if the last fuel will be sufficient for TEI

in the Apollo13 mission, the astronauts was very lucky because the SM problem happen BEFORE they use the LM engines/fuel/life support

but the MAIN purpose of the LSS is to MULTIPLY the number of moon landings/missions with each crew

a new crew arrive in lunar orbit, docks its CEV to the LSS, stay 3+ months in lunar orbit and perform 5+ moon landings/missions... they ONLY need to re-fuel/re-supply the resusable LSAM after each mission (like happen every day with the airplanes...)

WITHOUT the LSS and the reusable LSAMs, FIVE moon missions mean TEN rockets launched from earth and (about) $30 Billion spent!

WITH the LSS and the reusable LSAMs they only need to receive the LSS 3-months re-supply and the fuel/hardware/instruments for 5+ moon missions, then... with the LSS and the LSAMs already in lunar orbit... 5+ moon missions mean: one "superCLV" launch (with the CEV a bigger SM for LOI and TEI and a little EDS for TLI) and one/two CaLV launch with the LSAM "re-fuel cartridges", the LSS re-supply, etc...

TWO rockets' launched instead of TEN and over $25 Billions SAVED !!!

with one LSS module and 2/3 reusable LSAMs, 3/4 crews may accomplish 20+ moon landings/missions PER YEAR (with LESS funds!) instead of less than 15 moon landings/missions in 5+ years !!!!!!!!!!!!!!!

about the LSS costs... we don't need to send now three LSS made with two modules each... one LSS built with one module (and a second module sent when possible) will be sufficient fo the first moon missions

that LSS module don't cost so much because it may have the same weight of one CEV/SM/LSAM system (about 70 mT with the engine/fuel for its LOI) and can be launched with ONE CaLV (and only ONE time in 20+ years!)

it may be simple like the Skylab: a big pressurized module, with life support, solar panels for energy, and space... space... space... space... since it must only "store" 6+ months of life support (food, water, oxygen, etc.)

if the big ISS needs only two Progress per year for its (FULL) re-supply, each LSS module will needs only an ATV-like (9 tons payload) cargo vehicle sent ONE time per year

I think that each (20+ years life-cycle) module may costs around $2B including the CaLV launch... it don't need a special vehicle for re-supply but only part of the CaLV payload sent with the LSAM's fuel, etc.

the LSS can't "become decrepit like the Mir" because it will be NOT built like the ('6o Soviet technology) Mir and it WILL HAVE a continue "manned maintenance"

the "occasional orbital reboosting or adjustment" will be (simply) performed with the CEV or one of the LSAMs docked to it (like with the ISS)

about sun flares... an orbital-shelter in the LSS module may be an "extra" (for "extra safety", of course) but a lunar-shelter will be better... and... with MANY resusable-LSAMs... ALL the astronauts in orbit (in the CEV and/or LSS) can LAND on the moon in A FEW HOURS... while... if a sun flares will happen without a CH-lunar-shelter, without a CH extra life support, without the reusable-LSAMs to land on the moon, without an LSS-orbital-shelter, without the LSS extra life support, etc... the astronauts must only depart immediately from the moon (or from moon orbit) and come back to earth while the sun flares' radiations burns them...

last but not least... the "reusable-LSAM" is a VERY GOOD idea (simply!!!) because a "reusable (and already very expensive) airplane" is BETTER than a "100%-expendable-airplane"... with EACH airplane scraped after ONE flight !!!

.


[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]

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#5 2006-06-06 04:41:50

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: gaetanomarano Lunar Space Station

two things

1) Gaetanomarano, thanks for replying without the use of all the garish colours it makes your post easier to understand and actually increases the likehood of your point being put across and to get a reasoned reply. (I have simply gone past a lot of your posts with all the lurid colours just to read the replies so any valid points you have had are being ignored)

2) Back on topic, The Moon is not a very good place to orbit it is under the influence of Earth and since it is tidelocked has an unbalanced orbital path. Any spacestation in the orbit of Moon will require a lot more fuel for constant altitude adjustments and fuel use will be expensive. Long term keeping of a lunar space station which has only one purpose that of delivering crews to the surface is not needed and since that station is not protected from the Sun by the Earth any crews will be at risk of solar storms. This indicates it will have to be a heavy structure and frankly is not needed right now

Using Lagrange points is possible but by there nature they are guite a bit further away from the Moon than simply being in orbit and so more fuel will be required by any craft leaving the lunar surface. And you are still unprotected from solar storms and you will still need to use fuel to keep yourself in that lagrange point.

A reuasable lander would be better kept at a lunar base and this would allow it to be protected from the elements rather than to be stored at a spacestation. The other point is that the lander would be using indigenous Lunar fuel and if stored at a lunar base would be located where the fuel is made so top ups could be easily accomplished. This would allow flexibility when we have already seen that accidents can cause chaos to spaceflight schedules. And creating garage type facilities for a reusable lander is a lot easier on the surface of the Moon.

So as far as I can see there is not presently a need for any permanent Lunar space station.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#6 2006-06-06 05:57:23

gaetanomarano
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Posts: 701

Re: gaetanomarano Lunar Space Station

...not a very good place to orbit it is under the influence of Earth and since it is tidelocked has an unbalanced orbital path. Any spacestation in the orbit of Moon will require a lot more fuel for constant altitude adjustments...

the orbital adjust don't need to be "maniacal"... little LSS orbital variations will need only little changes of CEV and LSAM flight plan... every 6+ months, a CEV can adjust the LSS orbit/altitude and that will not needs so much fuel like a weekly adjust

...only one purpose that of delivering crews to the surface is not needed...

I've already explained in my article and posts the giant advantages of the LSS

...crews will be at risk of solar storms...

no, they may simply land on the moon with the LSAMs and use the lunar-shelter (that MUST be built!)

...Lagrange points is possible but by there nature they are guite a bit further away from the Moon than simply being in orbit and so more fuel will be required by any craft leaving the lunar surface...

right

...reuasable lander would be better kept at a lunar base and this would allow it to be protected from the elements rather than to be stored at a spacestation...

the moon surface is better for LSAM's repair/maintenance but NOT for its refuel... if the LSAM must fly from the moon with its "next-landing-fuel" it can't lift any astronaut nor cargo

...indigenous Lunar fuel and if stored at a lunar base...

it may happen, but needs decades... now it's faster and cheaper to send the fuel from earth

...there is not presently a need for any permanent Lunar space station...

...only "save the astronauts' life" and "accomplish in ONE year MORE moon missions than a full VSE plan in the next 20+ years"!

.


[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]

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#7 2006-06-06 08:45:11

SpaceNut
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Re: gaetanomarano Lunar Space Station

-If the CEV fails during transit from the Moon, then you can't reach the station.

-If the LSAM acent can't reach the CEV, it can't reach the station either.

...The only concieveable situation I can think of where the station would present a real safety bennefit is after the LSAM acends to orbit but the CEV is non-functional, which would leave you in trouble.

There is a way but it is untried, transfer the fuel from the CEV to the LSAM for return trip engine burns.


If LSAM stage will not fire transfer the fuel from the ascent stage to the descent stage and fire it to get to orbit.

2) Back on topic, The Moon is not a very good place to orbit it is under the influence of Earth and since it is tidelocked has an unbalanced orbital path. Any spacestation in the orbit of Moon will require a lot more fuel for constant altitude adjustments and fuel use will be expensive.

I think this can be solved by am ION engine keeping a constant flow of energy going into each orbital pass.

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#8 2006-06-06 08:59:39

SpaceNut
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Re: gaetanomarano Lunar Space Station

Oh and it gets better, that if you are on the Moon at a much different longitude then the stations' orbit, you can't launch to it just any time you want, you would have to wait for some days for the Moon to rotate so the orbit overflies you. The LSAM just can't carry enough fuel to make huge plane changes.

Could refueling the descent stage and then using the ascent stage get you enough delta to make a plane change...

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#9 2006-06-06 09:23:31

GCNRevenger
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Re: gaetanomarano Lunar Space Station

Fuel transfer is alot of trouble and I don't think is worth it, especially since these are cryogenic fluids. The plumbing involved to go to/from the service module and the LSAM tanks would have to go through the capsule, which would involve at least two connections which would have to disconnect properly for safe seperation. You really have to consider how much trouble it is to mitigate a low risk failure mode.

The LSAM with refueled decent stage tanks could probably execute a modest plane change, but not a huge one. Where are you going to get the fuel though? If you are at a base on the surface, then you would want to stay at the base and not flee to a space station. It would be much easier to simply have a whole redundant life support system on the ground then a seperate station, perhaps with its own heavy radiation shield.

An ion engine doesn't have the kind of thrust required to correct from a signifigant orbital perturbation, and no ion engine powerful enough to move a 50MT+ vehicle has ever really been seriously contemplated, the amount of solar arrays needed would be huge.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#10 2006-06-06 14:39:12

RedStreak
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Re: gaetanomarano Lunar Space Station

An ion engine doesn't have the kind of thrust required to correct from a signifigant orbital perturbation, and no ion engine powerful enough to move a 50MT+ vehicle has ever really been seriously contemplated, the amount of solar arrays needed would be huge.

I'm afraid I have to agree with this on ion engines.  I give a vote of confidence for their usefulness and fuel efficency, but due to the amount of time they require its not practical on a manned mission where time is critical.  As I posted on a direct post regarding ion propulsion I'd limit it to cargo missions - and even then I must admit a stronger ion engine capable of lofting 50 ton paylods to the moon needs to be developed.

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#11 2006-06-06 19:57:45

SpaceNut
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Re: gaetanomarano Lunar Space Station

Fuel transfer is alot of trouble and I don't think is worth it, especially since these are cryogenic fluids.

It will be something that we will need to learn how to do and safely.

There is a way but it is untried, transfer the fuel from the CEV to the LSAM for return trip engine burns.

The plumbing involved to go to/from the service module and the LSAM tanks would have to go through the capsule, which would involve at least two connections which would have to disconnect properly for safe seperation.

I am sure that the CEV/SM does not get fueled from the inside of the capsule, so there is already the fixture connections on the SM side of things it would only require making sure that the LSAM side of things have the rights connections from the get go for this possibility. This does lend itself for the reuseability that we are looking for by doing so.

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#12 2006-06-06 20:05:00

GCNRevenger
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Re: gaetanomarano Lunar Space Station

No on both counts

We won't be refueling space vehicles in zero gravity, at least not for a very long time. We won't even have to do that for the first decade of Mars missions. There is no point in bothering with it, since it offers essentially no safety bennefits.

And there won't be a fuel connection between the CEV service module and the capsule itself, the capsule will even burn a different type of fuel most likely.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#13 2006-06-07 05:31:25

Austin Stanley
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Re: gaetanomarano Lunar Space Station

An ion engine doesn't have the kind of thrust required to correct from a signifigant orbital perturbation, and no ion engine powerful enough to move a 50MT+ vehicle has ever really been seriously contemplated, the amount of solar arrays needed would be huge.

I agree with almost everything said here except this.  Orbital corrections are generaly very mild manuvers requiring delta-v's of of a couple hundread of m/s a year at most.    These sorts of manuvers aren't time critical, it's not like the station is going to suddenly crash into the moon if it doesn't do the correction at that very moment.  So a ion-engine could quite easily provide the necessary delta-V (over a period of days or weeks, depending upon its thrust).


He who refuses to do arithmetic is doomed to talk nonsense.

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#14 2006-06-07 07:58:26

GCNRevenger
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Re: gaetanomarano Lunar Space Station

Even if ion power is possible, the size of the engine and associated solar array would be huge. Also, wouldn't it produce so much waste heat that you would need a cooling system, and the solar arrays themselves would lose efficiency with age due to solar/cosmic radiation. Would it really be any better then sticking with chemical?


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#15 2006-06-09 11:46:39

publiusr
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Re: gaetanomarano Lunar Space Station

I don't have a problem with a lunar station, so long as CEV is nearby. CEV may need to dock to the station if it has problem with life-support. It is a payload for the future of course. The more infrastructure you have, the better.

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#16 2006-06-09 12:13:36

gaetanomarano
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Posts: 701

Re: gaetanomarano Lunar Space Station

I don't have a problem with a lunar station, so long as CEV is nearby. CEV may need to dock to the station if it has problem with life-support. It is a payload for the future of course. The more infrastructure you have, the better.

as I've explained at the end of my article [ www.gaetanomarano.it/articles/009_LSS.html ] the LSS may give also a POLITICAL ADVANTAGE to NASA and ESAS because, if they use the early ESAS funds to build INFRASTRUCTURES on the moon and in lunar orbit, there will be LESS (or zero) probability that funds will be deleted or may have a big cut after half dozen of manned missions (read: "Apollo17")

and, "right", the CEV or the LSAM may have many different problems (not only the engines that don't work) at its life support, computer, pressurizations, hatch, energy, an astronauts that needs help in a better and larger structure, etc. etc. etc.

if the CEV and LSAM will be made with modular devices, a CEV malfunctions can be rapaired with a spare part/card that come from earth (while they wait docked to the LSS to have a long life support and don't finish the CEV life support that they need to come back to earth)

.


[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]

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#17 2006-06-09 15:01:54

Grypd
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Re: gaetanomarano Lunar Space Station

Political advantage will be gained by a permanent base on the Moon. Only when we have a series of these bases will there might be a need for permanent orbiting Lunar station.

Economically the lunar station does not make sense but a reusable lunar lander does. Of course this only applies if fueled by Lunar materials, wether aluminium oxide or methane oxygen stored at a lunar base.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#18 2006-06-09 16:02:43

gaetanomarano
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Posts: 701

Re: gaetanomarano Lunar Space Station

Economically the lunar station does not make sense but a reusable lunar lander does.

a simple single-module LSS don't costs like the ISS

it need only one CaLV launch and the price of half moon mission

it don't need to be complex but only a large space to store oxygen, food, water, tools, etc.

it don't need to have engines, fuel, etc. since the "house" of the astronauts will be the CEV

the CEV will live up to six months in stand-by but only a few weeks with the astronauts

with the LSS, the CEV may have up to six FULL months of life WITH the astronauts

.


[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]

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#19 2006-06-09 16:32:27

Grypd
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From: Scotland, Europe
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Posts: 1,879

Re: gaetanomarano Lunar Space Station

Why create all the hassle that is storeing cryogenic material in space when there is no need to. The advantage in the case of storing it on the Moon is simple structures that in shadow keep a constant low tempature.

Im sorry to say that there is no need to design and build a lunar station. The Moons lower gravity gives all the benefits that is needed. Though I have to admit there is an economic case for an orbiting Earth spaceport.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#20 2006-06-09 16:54:23

gaetanomarano
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Posts: 701

Re: gaetanomarano Lunar Space Station

Why create all the hassle that is storeing cryogenic material in space when there is no need to. The advantage in the case of storing it on the Moon is simple structures that in shadow keep a constant low tempature...

the moon-base-only architecture will be possible only when HIGH quantities of (low cost) ISRU propellants will be REALLY available

before that day, ALL explorations based on moon-fuel are only sci-fi

before the "ISRU-days", the refuels of the LSAMs must be done in orbit (with or without the LSS) for the simple reason that all the fuel come from earth and, land the fuel on the moon, needs to waste great part of this precious fuel

.


[url=http://www.gaetanomarano.it]gaetanomarano.it[/url]
[url=http://www.ghostnasa.com]ghostNASA.com[/url]

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#21 2006-06-09 19:22:45

SpaceNut
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Re: gaetanomarano Lunar Space Station

Economically the lunar station does not make sense but a reusable lunar lander does.

Why create all the hassle that is storeing cryogenic material in space when there is no need to. The advantage in the case of storing it on the Moon is simple structures that in shadow keep a constant low tempature...

a simple single-module LSS don't costs like the ISS

it need only one CaLV launch and the price of half moon mission

it don't need to have engines, fuel, etc. since the "house" of the astronauts will be the CEV

before the "ISRU-days", the refuels of the LSAMs must be done in orbit

Wrong gaetanomarano, the CaLV would only delete the LSAM from it but with no CEV capsule and SM from the CLV to control it to lunar orbit. Also with no engine it will not stay in orbit for very low whether it is a high one or low. Yes it may take years but once it is tumbling uncontrolled it is no longer worth anything. You need engineers or thrusters just for this one point. The CEV has no extra fuel for this purpose unless you want to make each launch cost more.

gaetanomarano you also miss read Grypd post of resupply fuels being stored on the lunar surface not made there. But you brought up the point that you would also need a new lunar lander as well to deliver the quantity of fuel to the surface.

Your estimate of the LSS would like be more like the cost of Orbital Workshop as it was initially known
Skylab plus inflation and the cost of the launcher plus additional engineering to make it happen.

Cost of the hardware must not exceed $200 million (excluding launch vehicle and the long-duration subsystems module). Cargo resupply and crew changes were to be carried out using Apollo Applications- modified CSMs (limited to three Saturn IBs per year).

Crew Size: 3.00. Design Life: 600 days. Orbital Storage: 730 days. Typical orbit: 427 km x 439 km at 50 degrees inclination. Length: 36.12 m (118.50 ft). Maximum Diameter: 6.58 m (21.58 ft). Span: 21.00 m (68.00 ft). Habitable Volume: 361.00 m3. Mass: 76,295 kg (168,201 lb). RCS Coarse No x Thrust: Reaction wheels. Electrical System: Solar Panels, 2 Wings + 4 Windmill x 14.94 m long. Electric System: 11.00 average kW.

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#22 2006-06-09 20:12:36

gaetanomarano
Member
From: Italy
Registered: 2006-05-06
Posts: 701

Re: gaetanomarano Lunar Space Station

...the CaLV would only delete the LSAM from it...

the way I suggest is a superSLV-like rocket with a 150 mT payload (to launch the entire "expendable" moon mission)

but also the standard 125+ mT (the "new" payload is still unknown) may be sufficient

it needs only a simplified LSAM engine and the fuel the LSAM burns for LOI

since the total weight of the CEV/SM/LSAM is around 70 mT, the LSS module may weigh up to 55 mT + the LOI engine and fuel (jettisoned after LOI)

since the module don't has engines, tanks, etc., its internal volume may be like six CEVs or three LSAM cabins

and this is only the space of the LSS' module... the full space available for the astronauts includes the CEV/LSAM docked

the module will be used only to store all the things the missions need: extra life support, tools, experiments, spare parts, etc.

...Yes it may take years but once it is tumbling uncontrolled...

the orbital reboost will use the CEV or LSAM engines/fuel (like the ISS)

a possible alternative is to use a fixed engine/tank and refuel it, but I think is more complex and risky

...CEV has no extra fuel for this purpose unless you want to make each launch cost more...

the CEV is already planned to have extra-fuel to change its lunar orbit

however, the CEV for reusable-LSAM architecture MUST have super-SM since it must store the fuel for LOI and TEI (like the Apollo)

the extra weight may be around 15 mT but it don't need another rocket

the CaLV (or, best, the superSLV) will be sufficient to send one CEV + its superSM + one LSAM refuel + the LSS resupply

I think to the CaLV (or SLV) not like a rocket but like a "multipurpose-space-truck" with the payload used for different and mixed configurations

...of resupply fuels being stored on the lunar surface not made there...

probably I don't understand this point

however, before the "ISRU-days" the reusable-LSAM don't need extra-fuel on the lunar surface

since it come from space (like the expendable-LSAM) if will only need the same fuel of the LSAM after LOI (but I don't know the NASA figure about this point)

...Skylab plus inflation and the cost of the launcher plus additional engineering to make it happen...

it's too complex to evaluate the LSS module form the Skylab, the inflation, etc. etc.

I have a very simple way to evaluate its (possible) cost...

the CEV and the LSAM are two pressurized vehicles with like support, energy, etc.

the LSS module is like a CEV or a LSAM cabin, but six times the CEV volume or three times the LSAM volume

well... I don't think that an LSS module (that will be used for 10+ years) may cost more than six CEV capsule or three LSAM cabins

if you know the extimated cost of a CEV (only the capsule) multiply it by three/four (not six, because each CEV has the very expensive communication & navigations system, spacesuits, etc. that we don't need to put six times in the LSS...)

I think that one module may cost max 1.5B + the CaLV/EDS to launch it

.


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#23 2006-06-09 20:45:34

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: gaetanomarano Lunar Space Station

it needs only a simplified LSAM engine and the fuel the LSAM burns for LOI

The LSAM does not preform the LOI it is the EDS that does this with the much more powerful pair of J2-x engines that you have not on your SLV.


since the total weight of the CEV/SM/LSAM is around 70 mT, the LSS module may weigh up to 55 mT + the LOI engine and fuel (jettisoned after LOI)

since the module don't has engines, tanks, etc., its internal volume may be like six CEVs or three LSAM cabins

unless you have a docking port under where the engines are jetisoned from you only have a single port to dock the CEV to and none for the LSAM which would bring the crew to lunar surface.


...Yes it may take years but once it is tumbling uncontrolled...

the orbital reboost will use the CEV or LSAM engines/fuel (like the ISS)

You do know that the ISS is boosted by sending up a seperate progress to refuel the russian module that does the boost. I think using the progress engines are a last resort.

I have not heard of any plans to do the same with the CEV but if so this would make the Capsule SM unit larger for this purpose. This would also mean a change would be needed as well for the second stage size as well of the CLV.

the CEV is already planned to have extra-fuel to change its lunar orbit

Simular problem but made worse in that now the EDS from the CALV would also need to be redesigned as well as its stages.


however, before the "ISRU-days" the reusable-LSAM don't need extra-fuel on the lunar surface

Huh.. if the LSAM is a 2 stage you loss the capability after 1 landing and return even if you do refuel it. Also a single stage to lunar surface needs refueling capability before it can go back up to the LSS.

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#24 2006-06-10 04:08:32

gaetanomarano
Member
From: Italy
Registered: 2006-05-06
Posts: 701

Re: gaetanomarano Lunar Space Station

...LSAM does not preform the LOI it is the EDS that does this with the much more powerful pair of J2-x engines that you have not on your SLV...

in the ESAS plan, the EDS performs only the TLI with its J-2x engine, then, it will be jettisoned and the LOI will be performed by LSAM engines

"my" refuel tank needs the same EDS, the same J-2x and a simplified engine for LOI

...have a single port to dock the CEV to and none for the LSAM...

the module will have a large surface/dimension to put MANY hatches, not only on its top and down

...a seperate progress to refuel the russian module that does the boost...

the LSS reboost can be done with the CEV engine or with LSAM engine or with the LSS module engine (not jettisoned and refueled)

NASA may use the best and most reliable option

...a change would be needed as well for the second stage size as well of the CLV...

the newCEV already needs a larger SM to perform (both) LOI and TEI (like the Apollo) + LSS reboost

the CLV is unnecessary, all launches will use the SLV like a space-truck with mixed cargo: CEV, LSAM, refuel, resupply, tools, etc.

...a single stage...

a single stage LSAM may weigh less than a two stages since it will be simpler, with less tanks, engines, structures, etc.

.


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#25 2006-06-10 06:42:10

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: gaetanomarano Lunar Space Station

"my" refuel tank needs the same EDS, the same J-2x and a simplified engine for LOI"

You need more then just LOI though, you also need power for ~2 weeks to operate the tanker until docking, you need maneuvering jets to keep it steady and point the main engine, you need communications for remote control, sensors to determine orientation, and you need computers to coordinate everything. Its not just LOI! If you have to expend one of these for every two Lunar trips, then that largely defeats the purpose of having a reuseable lander in the first place.

the LSS reboost can be done with the CEV engine or with LSAM engine

This fuel has to come from someplace, the CEV will already only carry enough fuel for TEI, otherwise it would push half-empty tanks home for no good reason, so it will have to come from lander fuel. This will reduce the number of flights you could make to a Lunar station anually and further reduce the bennefit of reuseability.


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