Archive for the ‘Lunar’ Category

From Hobbyspace, highlighted by Transterrestrial Musings:

The program of record (i.e. Ares I/V/Orion/Altair), which exceeds the expected budget substantially, will no longer be in the options table but kept separately just as a reference.


The historic words have been spoken. Now for a better future for NASA, for spacefaring and for humanity.

The Augustine panel has been good beyond my wildest imaginations. (My imagination is extremely pessimistic.)

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Jeff Greason is a rational person who simply gets it. It is mind boggling how completely opposite from someone like Mike Griffin he is.

See Jeff’s presentation with the Augustine Panel.

Paraphrasing, “we could go to Mars with Ares V but we shouldn’t – cause we couldn’t stay anyway”. Exactly. That’s the problem with NASA. (or the major one)

I bet he will be ignored completely.

Also, I would like to work for that guy. Too bad because of ITAR I couldn’t work in the USA.

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Concept art of lunar bases tends to show spherical or cylindrical structures, but they suffer from one problem: radiation. (Both of the gamma / particle and heat kinds). The lunar environment has lots of solar and cosmic radiation. Nights also last for two weeks, during which a badly insulated thing will freeze.

If you bury your moon base under a layer of regolith, you can avoid both of these problems. You don’t have to bring heavy shielded modules from earth, or heat during the night with nuclear batteries. Regolith is thermally well insulating.

NASA seems to catch onto this a little in some clearly low budget “alternative configuration” posted at Nasawatch, but it only goes halfway, putting some shallow “berms” around cylindrical structures, for shielding.

In reality, lunar bases (if crews are to spend many lunar nights there) would probably be completely buried.

Burying might actually be easy: a small automated/remotely controlled snow blower style rover vehicle might be able to do it slowly with the help of just solar power. Since there is no air, tiny amounts of regolith can be thrown large distances. A thin wheel with whiskers spinning rapidly would throw the sand to the wanted direction. A lunar day is 336 Earth hours. Even if the “regolith lobber” robot can not survive the night and is expendable, it could manage to move significant amounts of regolith. A sub-MER size rover with large solar cells could throw perhaps 20 grams of regolith per second, or 72 kg in an hour. That’s 7 tons if there is 100 hours of efficient sand throwing time.

Say, landing at 50 hours from dawn, setting up 50 hours (survey area, lower rover from lander, unfold solar cells etc), operating for 150 hours (which includes maneuvering 50 hours and sand lobbing 100 hours), and finally stopping at a low sun angle 50 hours before dusk.

Such concepts are probably unlikely to work in an atmosphere, though I would be happy if proved wrong. The 2009 lunar regolith excavation challenge is coming up, after all…

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I’ve been an opponent of Ares I for quite a long time (not from the beginning though, but I have become more of an optimist since, regarding better  ways). In light of these things, it might seem that the huge political and bureaucratic machine that is NASA can finally start turning around. Mike Griffin in his time changed the direction of NASA very quickly by firing a lot of leaders and starting the development of the Orion capsule and the Ares rockets based on the ESAS three month quick study. On the other hand, ESAS’ conclusions somehow ended with the industrial base not changing significantly. Still solid rocket boosters for example. So one can question, did the direction really change in that sense?

But if there’s a real change, it could very well be that an Orion (or some variant or derivative of it) could fly on an EELV. It is strange to an outsider that the ESAS (with references to unpublished appendices) claimed how EELV:s are less safe and more expensive than Ares I. Then there’s the whole “black zones” kerfluffle, that warrants its own entry, if true. Basically and oversimplified, NASA said the EELV:s need new upper stages since they have tiny engines in second stages which need vertical trajectories. The vertical trajectories are a problem in case of an abort, since they result in high G loads on the way down. But some people say the EELV guys were not consulted on this, and that they could easily fly shallower trajectories. Maybe I’ll post more about this some day with better references.

There are rumors around that a new NASA administrator has been chosen. While I do not think an EELV solution itself for US manned space access is smart in the long run, it is pretty good in the short run (next five to fifteen years). What is much much more important is that if there are multiple launch providers and the payloads are switchable between rockets, then that is a field where improvement is very easy and cheap, since one can introduce new launchers to the “launcher mix” without jeopardizing the whole “program”. (The program mentality is one big problem as well.) NASA is the biggest worldwide player in tonnage to orbit, by a huge margin. They have the bucks, and thus they control the spacefaring development of the world.

A lot hinges on the new NASA administrator choice. (Unless Griffin was really a puppet too.)

Expect to hear little

I expect mainstream aerospace journalism to be as apathetic about all this as before too. It seems there are relatively few technical people there, and hence they don’t recognize the whole existence of the difference between technical solutions, they are all equally good. To them, it’s just a political definition if Ares I works or not. Even programs like NASP, people like Rob Coppinger somehow think failed because of “politics” – I find they failed because of grossly unrealistic and unjustified technical assumptions right at the beginning. That again warrants a separate post (there are books about it already).

So, if you’re a politician, a space business person or a technical person working on the space sector, maybe you should read something else than the postmodern relativist lazy mainstream media if you want real insight… And probably actually at least many of the experts have already moved to other medias.

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I wrote this architecture proposal, FLEX, a few years ago. It analyzes NASA’s approach that the ESAS study picked and notices how most of the mass in a lunar exploration stack in LEO is actually liquid oxygen. By using a propellant depot, the LOX can be lifted with tankers and any launchers imaginable (I wouldn’t use a Pegasus though). The rest of the stack is also naturally divided into about 20 ton chunks: EDS with its hydrogen, the CEV crew vehicle (Orion) and the LSAM lander (Altair).

No new heavy lifters need to be developed, there is enough US, nevermind world launch capability to support a moon exploration program. Launchers can also be improved on the run, because they are not tied to the single use, nor is the use dependant on the single launcher, and because they can fly often, hence improvements are worth the investment. This all could be achieved much sooner and cheaper than the current approach, and is much more robust for the future.

Go read it if you haven’t.

There are some comments at an old Nasaspaceflight.com thread that deal with a lot of the common questions about it.

I really don’t have the faintest idea of the background knowledge level of the readership here so I don’t know how much basics I should give, so feel free to ask in the comments if anything is unclear.

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From Slashdot via Hobbyspace.

There’s some confusion regarding Shenzou 7 (the upcoming mission), 8, 9 and 10 forming a space station by snapping together in orbit.

The orbital module of Shenzou can stay behind on orbit just fine, it can function as an independent spacecraft, while the crew returns with the crew module. They have done this with previous Shenzous as well. If the OM:s (or some of them) have docking ports on both ends, I don’t think it will be that hard to dock and chain them.

I don’t remember if they have demonstrated rendezvous and docking yet in any scale. I imagine it being quite a lot easier nowadays with better comms and computers than during the days of Gemini.

Of course, this is a model for orbital propellant depots as well. Too bad the western space agencies are too corrupt and self-absorbed to think anything like that.

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The Constellation program has been going on for about 3 years. Kicking off with the ESAS study of a few months, it still hasn’t settled very much about the architecture. Even the number of solid segments and liquid engines on the Ares I and V launchers are uncertain – issues which mean a lot for the infrastructure. A high launcher means VAB rebuilding. A heavy launcher means new crawler ways. Everything seems to be reassessed constantly.

Ed Kyle has documented the Ares I and Ares V history, while I discussed the future of Ares V here, the picture is from that post’s presentation. At the moment the design has moved along from the first configuration in January, having added half-segments, more core length and a sixth RS-68. No move to HTPB rubber in the boosters yet or composite wet parts EDS IIRC.

Ares V Evolution, Muirhead Jan 2008

Ares V Evolution, Muirhead Jan 2008

People from inside NASA have lamented the lack of conceptual design skills there, since the design keeps changing too much because of flaws being discovered.

There’s the classic story from Apollo, when Wernher von Braun simply didn’t believe the mass numbers the spacecraft people gave him, and vastly oversized the Saturn V – and it turned out that eventually all the performance was needed.

But the leaps in capabilities were huge back then. Now rocketry is routine and there is already one example of a lunar architecture to compare to. Not many new engines need to be developed for example, and a lot of the hardware is derived from STS and other flying systems.

So how is it that an agency getting 15 billion dollars a year is failing to pin down the mass numbers any better? Over ten ton sudden shortfalls in LEO mass seem to be a lot. Of course, it is a hard problem, and it’s easy to carp from the sidelines, but still…

What will the payload landed on the moon be? What propellants are used? What is the Altair’s or Orion’s mass? And work back from there to TLI mass and ultimately to launch from Earth, all with generous margins. And it has seemed that a certain cycle has formed. First a solution on Ares I is based on some logic linking it to Shuttle hardware, infrastructure or Ares V with common elements, which should save a lot of money and time and keep the workforce etc etc. Somewhat later, rumors about a severe performance shortfall on either launcher start circulating. Then after a while NASA announces a new configuration where the commonality is disrupted. And again forward we go.

The decisions made earlier are not supported anymore because new facts (performance problems) were realized later. But these decisions can’t be revisited. (Flying Orion on an EELV is one.) ESAS is referred to as having looked at all that, discarding it. Yet when some changes happen in Constellation, ESAS is mentioned as “only a 90 day study, how much can you expect from it?”. The consistency of decision justification is lacking. Ability for honest introspection is a rare thing for persons or organizations. I am just an outsider and don’t really know what’s going in inside there, maybe all is just exaggerated, but it looks troubled to me. How much can there really be progress if nobody knows what the launchers will be like in the end anyway?

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David Harris finally wrote the article on NSF that was a long time coming. Ares V might very well move to 5.5 segment SRB:s. There goes the commonality with Ares I.

Mike Griffin, Scott Horowitz, Doug Stanley and the others might have picked an architecture with too little margins and too many limits.

In other links, the Space Review has an article discussing how NASA (as well as the public and the contractors) is misguided with it’s “program mentality”, or something in that vein, I haven’t read it yet, but if Monte Davis comments that it’s good, then it probably is.

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ESA’s Architecture for Exploration Study (AES) is overviewed in Lunar Base Quarterly 1/2008 (EDIT: to be clear, the Quarterly was released in January):

Lots of Ariane 5, Angara and Soyuz launches with space docking, a space station in Earth-Lunar L1 and many new crewed and non-crewed craft and capabilities.

They had a red team / blue team approach at this point.

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