glaurung: (Default)
Posting this here so I can find it again.

Space travel is expensive and difficult, so we humans do very little of it. We launch satellites, we send up astronauts and sometimes space probes, but not many. The market for space launches is small and almost entirely government subsidized. Which has crippled attempts to make getting into space less difficult and expensive, which has prevented the development of uses for space that would justify the development of less expensive ways to get there. Egg, meet chicken.

This state of affairs is frustrating for space enthusiasts who feel that humans ought to be colonizing other worlds, living in space, and generally going out beyond Earth in a big way. Space enthusiasts (and I am one) tend to be susceptible to trying to invent a way that "doing space in a big way" could be economically sensible. Far too often, they do so without bothering to do the math or the fact checking required to determine if their latest scheme makes any actual sense or not.

Hence Helium 3 mining on the moon (for a method of fusion that we do not know how to do and if we did know, it would be far cheaper to mine it from supplies on Earth, or manufacture it by making tons of tritium and waiting for it to decay), Solar power satellites (a rube goldberg way of making electricity where just building the solar power installations down here would be only 3x less efficient and be 10x or more cost effective). And so on.

One meme that I keep seeing come up is how there are mountains and crater rims on the north and south poles of the Moon that get eternal sunlight, right next to craters that are eternally dark and therefore contain ancient ice. The idea is that all we need to do is install solar panels on those mountains and we will have oodles of solar power for mining lunar ice, then using that to fuel our vast armada of space ships/keep our space colonies supplied with water/what have you.

So let's do a bit of math )
glaurung: (Default)
As the New York Times reports, NASA is planning on discarding the shuttle in favour of manned and unmanned disposable booster rockets. The first stage of the manned rocket will be a refitted Shuttle solid rocket booster; the second stage will be based on the J-2 rocket engine, last used in the Apollo program (in other words, it's a redesigned Saturn V third stage). The unmanned cargo booster will basically be a shuttle external fuel tank fitted with the Shuttle's main engines, assisted by dropaway solid fuel boosters, again borrowed from the Shuttle. The article emphasizes that these hodgepodges of off-the-shelf and out-of-the-museum designs are what NASA can afford to deploy given its budget constraints.

This sounds all too familiar. I looked in William Burrows's history of space exploration, "This New Ocean," and found the precedent: back in the late 60's the Apollo program was being phased out. The stingy idiots in the US Congress weren't even willing to fund enough missions to use up all the Saturn rockets that had already been built, forcing NASA to use the last couple of them as the world's most expensive lawn ornaments.

But America had to continue a manned space program because the Russians had one, so President Nixon asked NASA what America should do in space now. NASA suggested a reusable cargo-carrying space plane, launched into orbit by a reusable suborbital winged booster. Both stages would glide back to earth and land on an ordinary airstrip. The advantage of a space plane over traditional boosters was not that reusable spacecraft would be all that much cheaper than throwaway spacecraft, although with a lot of creative accounting, this became the big selling point NASA used to get funding for the Shuttle. Rather, the space plane was an improvement over disposable boosters because it let the astronauts return to Earth under something resembling controlled flight (reducing the danger of incinerating on re-entry), and it enabled them to bring cargo back from orbit.

NASA proposed using the space plane to build a permanent manned space station, which would act as a launch point for manned flights to Mars. Nixon looked at the cost of the Vietnam war and said OK, design your space plane, but do it on the cheap: forget about $15 billion, you've got $5 billion. We'll talk about space stations and Mars some other time. NASA should have told Nixon that the space plane couldn't be built for so little. Instead they took the concept and tried to bring it under budget by whittling it down to the nub that is the Shuttle, thereby wasting billions of dollars and killing the crews of Columbia and Challenger (both disasters were due to the Rube Goldberg external fuel tank/solid rocket booster configuration which replaced the original concept of a reusable winged first stage).

So here we are again, with NASA trying to develop a new space vehicle on the cheap and under budget constraints. If their new craft kills its crew at the same rate as the shuttle, and proves to be just as expensive and wasteful as the Shuttle, don't say I didn't warn you.

At least the shuttle represented a step forward technologically, in terms of controlled re-entry and the ability to bring cargo back to Earth. These designs NASA has divulged are huge steps backward. Yes, the proposed cargo booster would be the first heavy lift launch vehicle since the Saturn V. But it can't bring cargo back to Earth. In terms of control (which translates as safety) on re-entry, the proposed crew capsule will be no better than the Mercury, Gemini, and Apollo capsules. In terms of low-cost space flight yes, these designs will be cheaper than the Shuttle (just about anything would be), but putting things in orbit will still cost hundreds of dollars per pound.

If humans are ever going to have a real space program (instead of a program designed to funnel money into certain congressional districts), with high orbit permanent space stations, bases on the Moon, L-5 colonies, asteroid mining, and space manufacturing, we will have to dramatically lower the cost to get things into orbit. Designs for reusable single-stage-to-orbit, vertical take-off/vertical landing space vehicles have been on the drawing boards of visionaries for decades. For a long time those visionaries have hoped that their designs could be developed by NASA as the eventual replacements for the space shuttle. Well, now we know that isn't going to happen. Sure, NASA might go to the Moon again, and to Mars as well. But not on a sustainable basis: that would require actually investing money in a spacecraft R&D, and NASA would rather do things on the cheap.

Profile

glaurung: (Default)
glaurung_quena

June 2025

S M T W T F S
1234567
891011121314
15161718192021
22232425262728
29 30     

Most Popular Tags

Syndicate

RSS Atom

Style Credit

Expand Cut Tags

No cut tags