henry@utzoo.uucp (Henry Spencer) (03/03/90)
Marginally space-related: this week's cover story is the SR-71 retirement, with assorted photos I've never seen before. [My conjecture is that AW&ST decided "well, if they're retiring the things, they probably won't object to us publishing the photos we've been sitting on for years...".] NASA briefly reconsiders use of the shuttle to launch Mars Observer in 1992, as Commercial Titan is very expensive, but discards the idea after figuring in the costs of astronaut training etc. to mount a shuttle mission for it. Payload for the Feb. 16 Atlantis mission [yes, the one that's up now] is a combination spysat and snoopsat, with both digital imaging gear and communications-eavesdropping receivers. Launch will be at 0121 EST if it goes up on the 16th. [I'm curious -- is this consistent with the actual launch time this week? I haven't kept track.] White House orders NASA to get more input from outside sources, notably industry and the science community, on plans for the Moon and Mars. The White House, uh, *noticed* Lawrence Livermore's proposal to do a good fraction of NASA's plans at 1/40th of the price. Quayle says "We need to consider innovative ways of doing business... [past plans] may be bound by restrictions and policy which, while well intentioned, bow more to tradition than ingenuity". NASA picks 23 new astronauts, including USAF Major Eileen M. Collins (a student at the USAF Test Pilot School at Edwards), the first female pilot astronaut. Pictures of the LDEF retrieval. Columbia's crew photographed LDEF extensively (800-odd shots) to document its in-space state as thoroughly as possible, partly due to concerns about experiments disintegrating when exposed to air and gravity during return. [In fact, there wasn't much debris in the payload bay afterward, most things stood up well.] Columbia then maneuvered to fly belly-first, using the orbiter as a wake shield to minimize further space effects on LDEF. One minor incident occurred late in the mission, when radio interference slightly scrambled a state-vector update command sent up from the ground, and Columbia began rotating slowly (peak rate about 0.5 RPM). The crew was asleep at the time, but mission control woke them up and they sorted it out. Columbia retrofire will be a long firing well out-of-plane, to burn off a couple of tons of fuel and help set up the proper center of gravity for landing. Superbird B prepared for shipment to Kourou after last-minute amplifier problems fixed. Feature article on Lawrence Livermore's "Great Exploration" proposal, doing Moon and Mars bases by the year 2000 for total cost of about $10G (compared to NASA's 25 years and $400G). It's caught the eye of a lot of people; NASA's response has been very negative. The primary authors are Lowell Wood, Rod Hyde, and Yuki Ishikawa. The G.E. proposal is explicitly a minimal scheme, not an "absolutely first class" [translation: gold-plated] one like NASA's. Major points of note: - Reliance on existing technology. "The thing we plan to do use existing technology in forms and integrations that can be demonstrated on Earth in 2-3 years at a cost of $50-150M." No new launchers: hardware goes up on Titan 4s and Deltas, people on the shuttle or in Apollo-type capsules, with use of commercial launchers a possibility. 24 launches in 10 years. - Risks comparable to those accepted during Apollo, rather than the rather lower levels NASA prefers now. However, there are provisions for emergency crew return at all times. - Less early science. "The crew will all be trained scientists and engineers who will do science the way Charles Darwin did it during the voyage of HMS Beagle. Darwin was the only scientist aboard and his scientific work was ancillary to his other duties as part of the crew." For example, there is no major observatory as part of the lunar plans. Later science work would build on the GE infrastructure. - No unnecessary auxiliaries. Specifically, none of the numerous unmanned precursor missions (mapping and communications satellites, probes, and sample-return missions) that are bundled into NASA's plans. - Standardized inflatable modules forming an Earth-orbit space station and the lunar and Martian bases. Using current space-suit technology, inflatable Kevlar modules weigh one-tenth of what rigid structures do and can be packed much more efficiently at launch. The basic hardware for the space station, the Moon base, and the Mars base is *one* Titan 4 launch each. Modules would be 5m in diameter by 15m long, with double outer walls, metal end plates, and a multi-layer outer shield to provide insulation and meteorite protection. Seven modules, at under a ton each, would be joined around a central hub for the space station. The lunar base would be another seven; the Mars base would be four. They would be inflated at the destination, after which astronauts would enter and (in shirt sleeves, not spacesuits) put together the interior furnishings. Interior components would be modular and prefabricated, assembled and tested on Earth beforehand. NASA, um, has doubts. It questions the feasibility of the inflatable structures, but Wood replies that (a) NASA's own spacesuit contractors say the modules are practical, and (b) NASA's own lunar-base plan includes an inflatable dome 11m in diameter. Wood says that in general, all the GE technology is from NASA research or NASA-sponsored industrial research. NASA says having the astronauts assemble the internal hardware is "a huge flaw", but Wood says it is no more difficult than prefabricated home construction on Earth, and saves vast amounts of weight (the weight advantage is a factor of 2-3 even after furnishing). NASA says the cost estimates are wildly optimistic and omit important expenses. The basic GE plan, if started immediately, would test components for the space station and orbital fuel dump immediately and launch them in mid-1991. Design and procurement of lunar-mission hardware would start while water was being launched to the fuel dump, to be converted to liquid hydrogen and liquid oxygen and stored for the lunar mission. The lunar hardware would go up in mid-1994 and go to the Moon later that year, using a lunar transfer vehicle powered by RL-10 engines and fueled in orbit. Lunar equipment would include a rocket-powered "hopper", two lunar tractors, an emergency-return module, a greenhouse module, and enough food, water, and air to support four people for ten years in a "spartan" lifestyle. Once modules were inflated and assembled, a small "snow blower" would be used to cover them with lunar soil as protection against radiation and meteorites. A "soil roaster" to extract oxygen from lunar soil for use as fuel is an option, possible with an extra launch but not essential to the main program. The Mars mission hardware would go up in fall 1996, and would likewise be fueled in orbit, to leave early 1997. Two vehicles would go, one to be used for surface descent, the other a return vehicle to be left in orbit. Surface equipment would include a plant to extract oxygen from the carbon-dioxide atmosphere, an ascent module, scientific instruments, rovers, a hopper, and life support for a 400-day stay. Return would be in late 1999, with at least 1000lbs of samples. Part of the crew could stay on Mars, and more missions would follow. -- MSDOS, abbrev: Maybe SomeDay | Henry Spencer at U of Toronto Zoology an Operating System. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu