FGB to the Moon?

#40 by William Barton on 22 Apr, 2008 12:16
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Spacenick - 22/4/2008 7:05 AM

Shouldn't most of the Energia developsers still be working at RKK? I mean it's not nearly as long ago as the Saturn-V

Twenty years is a long time. Even with the same workers still available (assuming they're not busy doing something else), I bet it would be hard to put an LV back in production.
#41 by hop on 22 Apr, 2008 22:30
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William Barton - 22/4/2008 5:12 AM
I understand the line of reasoning there. It does seem a lot less reasonable than US concerns with using the RD-180. Then again, I'm not a government.
Regardless whether it is reasonable or not, Russia has spent a lot of time and money getting away from depending on Ukraine. There's no reason to expect that to suddenly reverse.

Keep in mind that Ukraine (or at least one powerful political faction) wants to join NATO, which many in Russia see as a direct confrontation. There are also the gas disputes. Russia wouldn't want to be in position where Ukraine could say "If you turn off the gas, we hold all LV related components up in customs"
#42 by Jorge on 22 Apr, 2008 22:50
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William Barton - 22/4/2008 7:16 AM

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Spacenick - 22/4/2008 7:05 AM

Shouldn't most of the Energia developsers still be working at RKK? I mean it's not nearly as long ago as the Saturn-V

Twenty years is a long time. Even with the same workers still available (assuming they're not busy doing something else), I bet it would be hard to put an LV back in production.

More to the point, early on in those twenty years the USSR collapsed and the Energia program was cancelled. A lot of Russian space workers left the industry during those times.
#43 by on 23 Apr, 2008 02:57
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Jorge - 20/4/2008 9:50 PM
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Jim - 20/4/2008 8:47 PM
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nobodyofconsequence - 20/4/2008 9:08 PM
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DMeader - 20/4/2008 6:10 PM
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nobodyofconsequence - 20/4/2008 3:26 PM One thing you don't need is the reboost capability - no atmospheric drag.
Lunar orbits are perturbed by the masscons and you'd need maneuver/reboost capability even without atmospheric drag.
Huh? Elementary perturbation theory tells you that any alteration will eventual reverse itself and we'll be back to the same orbit eventually.
So what if you slightly change orbit for a while. Its predictable, so you work it in to the mission plan.
Not exactly, lunar orbits are unstable. The subsatellites released on Apollo 15 &16 eventually crashed into the moon
Right. The perturbations caused by the mascons do not increase or decrease the total energy of the orbit, but they can increase eccentricity to the point that perilune intersects the lunar surface if not corrected. Being able to predict it is not enough. Reboost capability is mandatory for long-term presence in low lunar orbit.
Knew about the mascons and the sub satellites. Know that if you have a process that increases eccentricity, you can use the same process with different timing to decrease it. Meant by predictable that you actively adapt a orbit to maintain use of the asset.
You mean no one in 30 years commissioned a study to examine using the mascons themselves to stabilize orbits with minimum/no fuel? The state of the art in orbital dynamics is 1000x what it was in Apollo days, and the computers are a billion times better. It's cheap - few hundred K to a JHU professor for a few years and a couple of papers. Much better than thousands of kilo's of storable props to LLO. Thought that issue had been solved by now.
#44 by Sid454 on 23 Apr, 2008 03:28
Call me crazy but wouldn't the Mir/Salyut core be a better choice since it's a more fully self contained station?
As for TLI you just attach an upper stage to it or a solar ion tug.

As for compensating the any perturbations caused by mass concentrations ie uneven non spherical gravity why not use ion thrusters.

BTW on either craft I don't think the thermo controls would need very substantial upgrades to operate in the lunar environment.

As for the ECLSS the Russian hardware is more up to the task then anything western that has flown yet.

Until ISS all western space craft life support systems were strait open loop nothing was recycled.

Though the L1 point might be a better home for your station then low lunar orbit from a logistics stand point.

But the LLO station does have it's own merits such as one could visit the lunar surface from it in a very simple open lander then return to the station.

Include a small fuel depot that is restocked by robotic NEP or solar tugs one could easily explore many wide ranging locations on the lunar surface this way.

Also a more detailed mascon map that would inevitably result from such a station could be useful in finding minerals such as nickel and iron.
#45 by Sid454 on 23 Apr, 2008 03:30
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Jorge - 22/4/2008 5:50 PM

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William Barton - 22/4/2008 7:16 AM

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Spacenick - 22/4/2008 7:05 AM

Shouldn't most of the Energia developsers still be working at RKK? I mean it's not nearly as long ago as the Saturn-V

Twenty years is a long time. Even with the same workers still available (assuming they're not busy doing something else), I bet it would be hard to put an LV back in production.

More to the point, early on in those twenty years the USSR collapsed and the Energia program was cancelled. A lot of Russian space workers left the industry during those times.

Loosing the Energia was a huge loose to space exploration maybe even bigger then then Sat V since it was a more flexible and affordable vehicle.
#46 by hop on 23 Apr, 2008 03:34
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nobodyofconsequence - 22/4/2008 7:57 PM
It's cheap - few hundred K to a JHU professor for a few years and a couple of papers.
Not without an accurate model, which we are lacking especially for the far side. Kaguya and it's sub satellites should improve this situation significantly.
#47 by Sid454 on 23 Apr, 2008 03:59
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Jim - 21/4/2008 6:05 AM

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Iren - 21/4/2008 4:33 AM

1) First and second stage engines wich could be used for Angara-100 are on test phase right now. First and second stage engines for Ares V... not. We dont even know if they will ever work.
) First and second stage engines wich could be used for Angara-100 are on test phase right now. First and second stage engines for Ares V... not. We dont even know if they will ever work.
2) If Khrunichev decides to start real developing Angara-100, they already achieved several milestones. Thats not the same with Ares V.
3) Khrunichev announced some days ago that they are on shape to develope the Angara-100 spacecraft if necessary. I translate this as "we can do it, we got the knowhow and the necessary hardware, but we need the money". Give them some budget to develope that spacecraft and they will fly it before Ares V, I'm sure of that..

The RS-68 for the Ares-V exists

#3 is just marketing spin and not a valid point

The J2X doesn't exist yet also why are you so hard on the Russians anyway?

In many of your posts I seen you discount all things Russian often on questionable grounds.

I don't see the Russians pursuing a horrible design like Ares or being so bad at mass management they delete their landing system and redundant systems.

As for funding for Ares V that might be more fanciful then Angara-100 getting funding.

The US economy is a mess so congress will be looking at how to do things cheaper.

The Russian economy on the other hand is booming and at a historic high.

I doubt Ares will survive the next president let alone till 2015 when Ares V development begins in earnest.

If the US does ever return to the moon I doubt it will be with Ares or Orion but likely via some descendant of a private vehicle and the EELVs/Falcon .

The only way I see Orion and shuttle derived hardware having a chance is if they make some rapid changes to something along the lines of direct and show some real tests .
#48 by Iren on 23 Apr, 2008 08:13
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Sid454 - 23/4/2008 12:28 AM

Call me crazy but wouldn't the Mir/Salyut core be a better choice since it's a more fully self contained station?

That's been proposed, check on http://www.russianspaceweb.com/los.html, its far better than sending a FGB
#49 by Jim on 23 Apr, 2008 11:52
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Sid454 - 22/4/2008 11:59 PM

In many of your posts I seen you discount all things Russian often on questionable grounds.

Because you keep bringing up Russia projects that don't exist beyond power point and are not being actively worked.

Bad or good, Ares and J-2 is being actively developed as we speak.
#50 by Bill White on 23 Apr, 2008 15:32
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Iren - 23/4/2008 3:13 AM

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Sid454 - 23/4/2008 12:28 AM

Call me crazy but wouldn't the Mir/Salyut core be a better choice since it's a more fully self contained station?

That's been proposed, check on http://www.russianspaceweb.com/los.html, its far better than sending a FGB

News item:

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ESA considers cislunar space station for lunar exploration
By Rob Coppinger

The European Space Agency, Russia and Japan are all considering a cislunar orbital complex that could consist of a habitation section and a resource module that would provide power and fuel and possibly be a safe haven for Orion crew exploration vehicle crews.

Whether the FGB-2 could be a useful addition to a joint station (other units provide habitation and additional capabilities) would seem to be a question of doing trade studies.

Use FGB-2 off the shelf or build a new module?

LLO would not be a stable place, leaving EML-1 and/or EML-2 as the most logical destination.
#51 by Iren on 24 Apr, 2008 00:17
How often would be needed to correct a LLO spacecraft orbit? as in LEO, more or less often?
#52 by nacnud on 24 Apr, 2008 00:57
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How often would be needed to correct a LLO spacecraft orbit?

Alot more than in LEO, LLO is unstable due to mass concentrations (mascons) in the moon that chaotically affect space craft in LLO.
#53 by on 24 Apr, 2008 06:41
Not strictly chaos - for that you'd need a randomized element. Its just a single lumpy rock - not one thats changing (e.g. fluid core with thermal processes). In this case it's time reversible/invariant. Assuming you know the gradients, it may be that you can move the apsides occasionally to reverse the effects. Or something simpler. Depends.

Unlike LEO, where energy is dissipated. And the ionospheric drag is chaotic.