A New Architecture for Space Exploration

[SenorPeligro]

Forgive me if I'm retreading old ground. I'm totally dismayed by our failure to build on the successes of the Apollo Program, the Space Shuttle and yes the ISS and our lack of drive to expand new horizons. The human exploration of Space is currently stalled with no practical plans to explore beyond the Earth-Moon system.

Instead of complaining about this, I believe it might be interesting to lay out a possible set of architectures for a New Space Program.

Let's assume a worthy objective is the "Flexible Path" of a human space-flight program comprising of :

• A small scientific outpost on the Moon, minimally supported from Earth for a fixed duration
• Visit to Near Earth Asteroids and Mars
• A landing on Mars potentially leading to a fixed duration scientific outpost

Longer term goals:

• Trips to Asteroid Belt, sample recovery
• Expanded settlement on Moon and/or Mars

Firstly, no politics. This is about the future, not the past. Engineering is the primary concern here, economics secondary.

There is room for multiple designs and architectures in this discussion, I'm not looking for the one true way but ideas that can work together.

Also, no sci-fi. Assume a 30 year timescale.

So what do we need and how do we make it happen?

 

[Nothke]

There are some good things that are on the way, but just aren't given enough significance:

Mooncrete - or kind of concrete with Moon regolith as an aggregate. Could be used very well for building bases on Moon, it is a great protection from lunar radiation and wouldn't require massive structures to be brought to moon on rockets. However I still can't imagine how would you make it... Mix with water? what water? ...and what cement? and the process needs air, and standard pressure? How? I don't know, but it would be good to start thinking now!

Inflatable spacecraft - I think everybody knows this...

however if you think about propulsion... chemical is the only way (the one used now), and heavy lift rockets I guess.
I know shuttle is not an answer... Buran-class?... no. Just an skylab-Apolo kind one... no, many of them... and then assembled in orbit

And..... no politics? Well... if you don't want (bad) politics, the world can unite and we can make antimatter propulsion in less than 20 years!

I don't know... Let me think more, there are many ideas, I'll post something when I remember.

 

[menellom]

Well, the first step is developing REAL heavy launch vehicles. Something capable of taking large payloads to LEO and even further out. There is likely to be some progress on this front, meetings between some of the heads of NASA and people connected with the DIRECT proposal suggest that with the likely canceling of the Ares rocket NASA is considering the Jupiter rocket proposed by DIRECT, or at least something like it. The Jupiter 246 configuration could carry a little under 100,000 kg to LEO, almost four times the space shuttle's capability. While it will originally be adapted for the Orion capsule, it could possibly be adapted to carry future 'deep space' spacecraft. Which brings me to my next point.

The second step is, I think, a vehicle more suited to long distance travel. Orion looks like it'll be a great spacecraft for LEO, but there's no way we can seriously consider sending crews and substantial distance in a capsule. It's too small and it's not going to get anywhere fast enough. A larger craft that could be launched with the Jupiter rocket, or a 'mobile' station assembled in orbit seem like good approaches to me. But while space is nice, the key is going to be propulsion. Let's face it, 8, 9 month trips to Mars is no way to explore the solar system, you'd need ridiculous amounts of supplies, a lot of fuel to launch it all, and without some heavy duty shielding chances are all your astronauts'll by the time they land. It's going to be critical that any 'deep space' vehicle be able to seriously cut down transit time. VASIMR is looking promising, with a prototype to be installed on the ISS in another two years. They've been able to get it up to the 200kw range, but it's still a long ways off from getting us to Mars in a month, but I can see it happening within the 30 year timeline you set. At the very least lower power versions of the engine could be used for nearer locations like the Moon and nearby asteroids.

Third, habitats/stations - this is where I think the private industry really comes into play. Private sector projects like Bigelow Aerospace's module prototype could be what make the commercial space station a reality, and I've heard they're already working on a designs for a lunar habitat. Imagine over the course of a decade or two having not one, but a dozen ISS sized stations in orbit. As far as the specifics of engineering on a lunar or martian base well... I'll have to think about that.

 

[SenorPeligro]

Heavy Lift is a must and without miraculous breakthroughs in space elevators or other exotic launch systems materialize, we are stuck with big, powerful, rockets. So a lift launch system is essential. Check.

I concur that the paired Orion capsule concept is ridiculous. We will need a much larger craft. Why not apply the engineering lessons we have learned to design a modular system that we can be lifted in modules and assembled in orbit? This seems to be well within our reach right now. Am I wrong?

It is also obvious to me (at least) that the lessons from the ISS are directly applicable to long term space travel. I think we need to start thinking of our future medium range space craft as being more like mobile space stations than capsules or "space planes".

If we assume modules, what kind of systems do we need? Can we draw inspiration directly from the ISS assemblage?

Propulsion. VASIMR looks very promising. What about the nuclear rocket designs? Are we still too squeamish?

 

[Nothke]

There are three things essential to the going to space in a short time:

1. Enthusiasm - or better said - Space Race, but you said... no politics. If "normal" people are not sitting around the campfire talking 'bout the shutties, than you don't have the widespread enthusiasm in it.

2. Budget - everyone knows that... Buran failed mostly because of the fall of USSR. And, now you see mr. Obama...

3. AAAAAND... if you don't mind the budget, the thing that brakes all the possible projects is certainly "safety concerns". You can think of something in 5 minutes, and make it fill with fuel, and launch it in less then a year... But you don't have the idea if it will actually work .. So if you want to send a for example picture-of-your-loved-one aboard a space shuttle, NASA would first spend a million dollars testing the photo on everything possible that can happen... heat, deflagration, detonation, radiation, humidity, tensile strength, twisting strength, how much force do you need to make it rip.... =) I'm just joking of course, but that's what they do...

So if you want something to happen, you need to find the balance between these three... I think the first thing when we need to start thinking about future projects is this balance.

 

[MeteorWayne]

To the OP, yes indeed this is covering territory that his been discussed many times over. There is likely to be one big thread in the end...

 

[menellom]

If you want you could combine this with my 'your vision for space exploration thread', I think it'd fit quite nicely. I'd rather it be meshed with that than with one of the 'zomg obama is killing space program' threads.

The mobile space station is an idea I like. Having a large station (something that could hold a crew of say... a dozen) that could travel someplace like the Moon or Mars opens up lots of options that a small vehicle mission doesn't allow, it's the same principle as having a permanent outpost on the Moon - if you have a long term crew there you can do a lot more construction/research/whatever than if you have to launch a separate mission every single time.

Picture a large station arriving in orbit around Mars. The crew would be able to make live observations of the planet, communicate with rovers on the surface in almost real time, if the station carried a capsule (or capsules) and a lander - sorties to Phobos and Deimos could be launched from the station.

Just a thought.

 

[Polishguy]

I think the most important thing is to develop our Super Heavy Lift (110 tonnes + to LEO) vehicle. It can be used for many different applications. For example, if we use a Shuttle-Derived vehicle, we might be able to boost the big external tank to LEO and use that as a space station. Add some solar panels to the sides, and a VASIMR engine, and you can go anywhere. It's big enough. Likewise, that vehicle can also be used for a moon base, a Mars-Direct style Mars Mission, or the use of that space station for asteroid missions.

We need to develop for versatility, so that Heavy Lift vehicle I described can be used for Moon, Mars, and Beyond, and as a space station. To service it, we should reopen the development of X-33, and its big brother, Venturestar.

As for that nuclear VASIMR, it's not necessary for Mars (too much fuel is needed for a 39 day trip in one launch), but for longer duration missions further out, its very helpful. Manned and unmanned missions to the asteroids and beyond can benefit from it. However, if you really want to increase payload for Mars missions, you'll need another nuclear technology, like NERVA. A NERVA engine can get an Isp of 900 seconds, as opposed to hydrogen/oxygen's maximum 450. NERVA is a good idea for Mars.

But, since this is an engineering-first thread, I'll throw out political and economic concerns, and just say Project Orion. If I were in charge of NASA, I'd invest in gathering up the aging physicists and engineers from General Atomic, give them a small arsenal of tactical nukes (the USA's nuclear arsenal includes artillery-shell nukes that can power the 880 tonne test orions, with the nukes themselves about 18" long), and set them loose on Jackass Flats. If we were serious about colonizing and exploring the solar system, we'd build Orion type vehicles.

 

[EarthlingX]

Two steps first:
1. Clean the warehouses of the working gear:
- Use remaining ETs, SRBs, SSMEs to get back to operations. (instead of selling them for shipping costs)
- Orion/Dragon second stage, make adapters compatible, at least, and
2. Ready the next phase:
- Plenty of engines to choose from :
- RS-68B (http://www.astronautix.com/engines/rs68.htm http://en.wikipedia.org/wiki/RS-68)
- NK-33 with a family, RD-170, RD-180, and newest, just done the first run, RD-191, or AJ-26 used on Taurus II
- RS-84, now with SpaceX
- Merlin
- Vulcain

I'm not even going to start with the second stage engines...

Make it upgradeable, modular, standard, reusable in steps. Fly-back boosters should not be such a problem.

There are also already payed for pieces of ISS still around. Get them up.

 

[holmec]

Ok, Constellation Program is a bust. Take time to mourn. But beyond the pessimism I find a reason to be enthusiastic.

I find it inevitable that gov't space programs could only get you so far. After that commercial can get you farther. But for decades NASA has squashed commercial space efforts. Now NASA needs the commercial side to be viable in the manned space because Congress has not and will not support a huge program like Constellation. that much is evident.

Yet, the international space community has grown and have similar dreams as we. Putting our efforts together would be wise. Space is not a joy ride anymore, its hard work. New concerns have arisen over the years, ie NEOs.

Commercial space has dreams too. Bigelow wants to rent time on a commercial space station, Space X wants to send astronauts, gov't and commercial to space. Virgin Galactic wants to sent the masses to suborbital space. This market is set to boom. And hopefully jobs will be created.

NASA ought to get back in the business of research and development to provide knowledge and know how to gov't efforts and commercial.

 

[aaron38]

In support of manned surface missions on Luna/Mars I came across a very common sense proposal. Any base is going to need solar power for all the electrical needs. And those power systems need to be designed and tested and it'd be nice to have them be cost effective as well. So let's put the military budget to work.

Is there any reason the Army's forward operating bases in Afghanistan can't be powered by the same basic power structure as a Mars base? The Army saves money and risk on trucking generator fuel out to these sites, and we gain a customer to get these systems designed, built, rugedized, beaten up, improved and mass produced. The system for Luna will obviously be configured differently for the day/night cycle, but it should be able to use the same basic modules.

The proposal even includes a 100kWe class nuclear reactor, and I would propose that any manned base have a mix of solar/nuclear power.