henry@utzoo.uucp (Henry Spencer) (04/15/88)
Editorial criticizing repeated reorganizations of the Aerospace Plane project, and also its deep secrecy, claiming that inadequate support for the program will lead to "bureaucratic strangulation". Soyuzkarta is interested in picking a US marketing agency. Geodyne is interested, as is Space Commerce Corp (which markets Proton). JPL tentatively picks Wild 2 as the target for Comet Rendezvous Asteroid Flyby, assuming a start next year. Tempel 2 was preferred, but is no longer possible after all the delays. CRAF launch would be Oct 1994 with arrival at Wild 2 in Feb 2001. [Cripes, the Soviets or the Europeans will be there first at this rate.] Instrumentation Technology Associates and U of Penn. find a possible problem for those planning to grow protein crystals in orbit: the crystals are fragile enough that high-G reentries might damage them. USAF interest in antimatter grows; it might be a reality early in the 21st century. Rand Corp says that near-term technology should be able to make and store antimatter at about $10M/mg [Robert Forward said a few years ago that at roughly that price, antimatter is competitive with *fusion* engines for in-space propulsion], and that supercollider technology might be able to lower that to $1M/mg. A shuttle-like vehicle about the size of Hotol could carry several times Hotol's payload by using about 35 mg of antimatter as its energy source. Engineering problems remain, notably the design of the actual rocket engine. A short-term approach would absorb the energy in a tungsten honeycomb and use that to heat propellant; this could yield 50-100 klbs of thrust at an exhaust velocity of 12 kps or so (this is 2.5 times H2/O2). More advanced designs could use a magnetic nozzle to confine the heated propellant, giving several hundred klbs of thrust at an exhaust velocity of maybe 200 kps, which "would enable every conceivable mission in the solar system". The most immediate need from the USAF viewpoint is a US source of antimatter; the only existing production facility is at CERN, which is partly Swiss and thus will not supply antimatter for defence-related work. Also of interest are high-energy exotic chemical propellants. The USAF is funding small studies on them, now that modern computers have made theoretical studies possible and laser technology has made experimental work practical. Materials under study are tetrahydrogen (H4), fluorine azide, asymmetric N2O2, and xenon-halide excimers. Tetrahydrogen would probably be the best propellant. Fluorine azide is too heavy to be a useful propellant, but is convenient for study work and also may lead to high-energy chemical lasers. Asymmetric N2O2, made by combining an excited oxygen molecule with a ground-state nitrogen molecule, could have an exhaust velocity of about 3.7 kps, 50% better than the best existing monopropellant. Most of these things are unstable at room temperatures, but storage in cryogenic ices seems practical. Ariane V21 launch on March 11 is successful, carrying GTE Spacenet 3R and Telecom 1C into orbit. Next Ariane launch is set for May 11. US is strongly opposed to use of Ariane to launch NATO's next series of comsats. The shuttle is officially prime launcher for them, but they might switch to expendables if shuttle delays continue. There is no doubt of Ariane's ability to launch them, since it is going to launch two British Skynet 4 comsats, which are almost identical to the NATO 4 series (not surprising, since British Aerospace builds both). The shuttle-vs-expendable decision for the first NATO 4 is likely to happen soon. "As far as the US is concerned, there is no way we will ever accept Ariane as an alternate to shuttle." The US *says* that its reason is that such NATO "infrastructure" contracts are normally required to stay within full members of NATO, and much of Ariane is built by countries which don't qualify (notably France). First US scientific launch since Challenger set for March 25: a small Italy/US/Germany satellite to go up on Scout from the San Marco platform [off Kenya]. [Actually this isn't such a big deal, since only the booster and a few of the instruments are from the US; the satellite was built in Italy and the launch crew is Italian too.] Estimate for cost of Canadian space-station contribution rises from $800M to $1.2G, raising some doubts in Canada. Official position is still "go", but this is a lot of money for Canada. Meanwhile, the Soviets were busy: one launch March 10th, two March 11th, one March 14th, and on March 17th they launched India's remote-sensing satellite (at a bargain-basement price, $6M). Soviets step up launch-marketing efforts. Photo of the Cyclone launcher (4000 kg into low orbit). New shuttle manifest. Two missions in 1988, TDRS Aug 4 and a DoD payload [thought to be an NSA Magnum listening satellite, as I recall] Oct 27. Missions 28 and 29 have been swapped to give more lead time for Magellan; 29 will carry another TDRS, then Magellan on 28, then an imaging spysat on 30. 31 will be the Hubble Telescope, officially June 1989 but more probably late that year. 32 will be LDEF retrieval, which has bumped the Astro-1 telescope package to 35. Also of note is 37, SDI Cirris plus USAF Teal Ruby plus SDI Spas (the German Spas platform carrying an SDI infrared-background-survey instrument), a new addition. There are two Spacelab missions in 1990. ISF goes up on 51, June 1991, while the NASA-leased Commercially Developed Space Facility is tentatively booked for May 1992; these two may in fact be the same thing, which would mean some reshuffling. The Aug 4 schedule for mission 26 is likely to slip to early fall. LTV and Italy's SNIA PBD sign agreement for development and marketing of a souped-up version of Scout, adding two SNIA PBD strapons and changing the fourth stage to another SNIA PBD motor. Big story on US Navy space systems. Little new except for an imminent buy of 9-10 new Navy comsats to replace aging FltSatCom and Leasat birds. The Navy might buy launch services commercially; the RFP asked bidders to provide this as an option. US Navy and NASA reach agreement on a complex barter deal to replace the Atlas-Centaur that was ruined in a pad accident. SDI speeds up work on a sounding-rocket particle-beam experiment, bringing its launch forward about six months to early 1989. This is at least partly an aftereffect of the cancellation of the much bigger particle-beam experiment SDI planned to fly on the shuttle. -- "Noalias must go. This is | Henry Spencer @ U of Toronto Zoology non-negotiable." --DMR | {allegra,ihnp4,decvax,utai}!utzoo!henry