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SpaceX Unveils Heavy-Lift Rocket Designs
FleaPlus writes "At the recent Joint Propulsion Conference, SpaceX's rocket development facility director Tom Markusic unveiled conceptual plans for how its current Falcon 1 and Falcon 9 commercial rockets can be evolved into heavy-lift rockets, ranging from a Falcon X capable of lifting 38,000kg to orbit, up to a 140,000kg Falcon XX (more than either the Saturn V or the 75,000kg shuttle-derived rocket Congress currently plans on having NASA spend >$13B building). SpaceX presentations also discuss a new Merlin 2 heavy-lift engine, solar-electric cargo tugs, adapting their current engines for descent/ascent vehicles fueled by Mars-derived methane, and a desire for the government to take the lead on in-space nuclear thermal propulsion while commercial focuses on launchers. In a recent interview, SpaceX CEO/CTO Elon Musk expressed his goal of lowering the price of Mars transportation enough to enable early colonization in 20 years, and his own plans for retiring to Mars."
That, my friends, is vision.
Not, "one day mankind must blah blah blah..." but: 'I'm planning to retire to Mars.'
Well, what I like about SpaceX is they've turned "rocket science" into "rocket engineering." As an interested outsider, they seem to have a strong focus on modular design, which aids in keeping costs down. It's basic bottom-up design, which usually leads to better and cheaper solutions than the top-down design work that government mandated engineering tends to be.
Design should always be a compromise between what you want and what is practical. The space-shuttle is what you get when you'd rather spend billions than be flexible in your requirements. And the worst part about that is you end up with such a bleeding-edge integrated solution, that you don't get to take anything away from it. You're always starting again from scratch.
I like nuclear thermal as much as the next /.er, but is there really any point in thermal rockets beyond attaining orbit?
For one thing there's the slight problem that you die during the transit through the Van Allen belts if you don't have a high-thrust engine or very large radiation shields.
And nuclear thermal rockets kind of suck ass for attaining orbit since you have to ensure that they land somewhere safe if they fail during launch; NASA's test plans for the early models involved polar launch where the flight path was designed to dump it in Antarctica or a remote part of the ocean if something went wrong.
I'm not sure the distinction is as clear as you're making it. It's not like NASA ever really built rockets. Rockwell International built the shuttle for them. They just set the spec and take bids, like any other government agency. The question is a somewhat less dramatic one: should the government specify the rockets it wants and get aerospace companies to build them, or should it let the aerospace companies build whatever they want, buy the products that fit best and make it work? For what it's worth (not much) my own view of the situation is that launch vehicle tech has progressed to the point where the latter approach is likely to save some cash. But let's not act like it's a difference between some free-market fantasy and a soviet design bureau.
Given a choice between free speech and free beer, most people will take the beer.
As 0123456 indicated, there are both a need for high thrust engines in space and huge risks with the use of nuclear-anything propulsion on Earth. In addition to passage through the Van Allen belts, we also need to consider the Oberth effect. When you're trying to leave a gravity well (such as Earth's), then thrust deep in the well has a higher effective ISP than equivalent thrust higher up the well.
Second, because of the risks of operating nuclear rockets in Earth's biosphere, it makes sense, that if you're eventually going to have a nuclear powered rocket to orbit, that you try it somewhere else first and generate a reliability record. Space is the "somewhere else".
When you're stranded high up on Olympus Mons
And your suit-gauge shows your O2's all but gone
Open your faceplate and face vaccuum's dawn
And go to your god like a spaceman.
Everybody gets what the majority deserves.
...but when I do, I prefer Falcon Dos Equis.
Stay orbital, my friends.
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Prisencolinensinainciusol. Ol Rait!
A far better vision would be much more expansive than Space X's -- which in my opinion consists of nothing more than building well engineered reusable reliable rockets at affordable prices.
Some guidelines:
1. Never use a rocket for material you can hurl or lift into space (i.e. non-G sensitive "mass").
2. Never use humans when robots can do much of the work (i.e. systems assembly, parts replacement, etc.).
3. Minimize the risks that humans face (keep them out of space as much as possible or well sheltered from the hazards there).
4. Invest only once. Build the factories to use materials from space in space.
You would start with (1) by throwing out the idea of rockets that can lift increasingly larger payloads. Instead you would invest one or more times in building ocean-equatorial based rail/mass guns [7] (to launch fuel, H2O, O2, food, "station"/"factory" subunits using solar power. This would lead to the construction of orbiting sky hooks which could augment the mass guns and/or pick up astronauts from SpaceShip Two type "ferries". Then SpaceTugs pick the astronauts up from the hooks and relocate them to ships under construction in "Dry Dock" (@ L1|L2).
But before one wants to engage in a vision like this one needs to *seriously* have a discussion regarding when molecular nanotechnology, i.e. when can nanofactories build nanorobots, when can nanorobots build nanofactories (allowing exponential expansion either on the Earth or in space). Nanorobots and nanofactories significantly lower the costs of access to space as well as the development of space (because they eliminate the need for biological "human" environments, safety systems, resource supplies, etc.). So one has to face up to the question of whether we want "human" or "nanorobot" development of space (when one path is clearly less expensive and likely to be more efficient), though perhaps less emotionally fulfilling.
Many engineers 'dis molecular nanotechnology, but for people who understand genome biology, that genomes are "software", that enzymes, esp. DNA polymerase, RNA polymerase and the ribosome are "assemblers", and who may have read Drexler's 1981 PNAS paper in which biological systems were cited as existence proofs for molecular nanotechnology, and perhaps who have read Nanosystems as well, the only questions that remain are how and when we could engineer systems of such complexity.
Then the question becomes whether we spend billions of $ on 40-50 y.o. visions (rockets to the moon or Mars) or equivalent or even greater amounts on say a 11-29 y.o vision... [1]. It is clear, at least to me, that the 40-50 y.o. vision provides some great stories, improves our technologies and lets us go where we have never gone before. In contrast the 11-29 y.o. vision frees most individuals on the planet from having to ever work again to survive, may indefinitely extend their lifespans and enables the evolution of humanity from a pre-Kardashev Type I level civilization to a Kardashev Type II level civilization [6].
I know which vision I'd be inclined to vote for.
1. Drexler's PNAS paper was published in 1981 [2]. Engines of Creation (Vsn. 1 was published in 1986) and (Vsn 2.0 published in 2007) [3]. Nanosystems (Eric's MIT PhD thesis) was published in 1992 [4]. Nanomedicine Vol. 1 by Robert Freitas was published in 1999 [5]. Almost all other nanotechnology "literature" tends to be long on either speculation or technical details and short on "vision" and facts. Those are the references for "science "visifact"ion.
2. http://www.pnas.org/content/78/9/5275.abstract
3. http://search.barnesandnoble.com/Engines-of-Creation/Eric-Drexler/e/9780385199735
http://en.wikipedia.org/wiki/Engines_of_Creation
No, I'm not espousing a free-market fantasy. If I had I would have advocated getting rid of NASA altogether.
What nasa should do is develop new technologies that will be required for space exploration. The end specs/components/implementation should be left to someone else however(in my opinion, of course). Preferably smaller, leaner, space startups. Companies that are willing to and capable of taking more risks. There comes a point when decreasing the chance of failure another .0001% isn't worth the next 10 million dollars. You do a run, if it fails, you do another one. The money spent on R&D is still there plus you now have practical data.
Making a material that absorbs heat better, or a combination thereof, or an entirely new system for dispersing the heat. Those sorts of things. They should be the realm of NASA. That should be the realm of NASA. Government funding is very good. Very very good. Its great at getting things invented. What government generally isn't good at doing until its forced on them is innovating. Thats what business is good at.
On the other hand, particularly lately with all these insanely rich but incredibly risk-averse asses out there, a lot of businesses are either slowing down massively on new tech or giving up developing new things entirely, letting someone else do it and then either stealing it or licensing it from them, and innovating with it.
Theres a good chance I can utilize technology X after its finished development... but if I put money into it now theres a chance it never finishes and those dollars are completely gone. On the other hand if Technology X is finished and working... well theres something I can do with it right now! It removes a layer of risk for new endeavors to not develop most of the technologies involved yourself.
Thats the main reason I think R&D should become even more the responsibility of government than it is now... for almost everything I feel it would improve everyones lives, and mostly abolish a lot of the industry patent lockouts that happen now, since everyone would have access at the same rate.
What's being discussed is not a "colony" in any normal sense of the word. It's a base. "Colony" implies a large degree of self sufficiency, which requires the most massive engineering engineering effort in the history of humankind to even get started. What Musk is doing is working on lower-cost spacecraft. Spacecraft that, IMHO, are still 1-2 orders of magnitude too expensive to make true colonization realistic. If all you do is go there and use some regolith for shielding and make some methane fuel using equipment shipped from Earth, perhaps growing some plants in greenhouses shipped from Earth, etc -- you're not colonizing. Namely, because not only could such a "colony" not independently expand itself, but if the shipments from Earth suddenly stopped, the next time something significant broke, the entire colony would die. You're not going to, say, jury-rig a new compressor out of duct tape and rocks. You couldn't even make duct tape itself without an entire petrochemical industry. A sustainable colony requires a mind-boggling amount of sustainable industry and the use of structures and devices engineered to be produceable by said industrial infrastructure.
But anyway, kudos to Musk for at least doing *something* useful rather than building palm tree islands or city-sized yachts.
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
It is actually reworked Kipling.
When you're wounded and left on Afghanistan's plains
And the women come out to cut up your remains
Roll onto your rifle and blow out your brains
and go to your God like a soldier.
Your "fair share" is NOT in my wallet.