AIAA report concludes that nine shuttles plus six Titans a year equals 0.0065%-0.024% of global stratospheric ozone depletion, and similarly trivial effects on acid rain and global warming. Nevertheless, they suggest that environmental effects get serious attention in design and use of rockets in the future.
Bristol Aerospace, International MicroSpace, Saab Space, and Thiokol sign agreement to jointly build Orbital Express, a new small solid-fuel launcher with a payload of up to 400lbs to low orbit. They plan to offer launch services from Poker Flat in Alaska, Wallops, and the hoped-for commercial Spaceport Florida at the Cape.
Large story on Hubble. Scientific results are starting to come in fairly briskly, but they are not quite at the earthshaking level that was hoped for; it's good but not great science, for the most part. Ground-based observatories are starting to catch up on clarity and faint objects, since they've had a decade of development while Hubble launch plans slipped steadily from the original 1983. Hubble is expected to retain major advantages in angular resolution (where the ground folks are well behind) and ultraviolet work (where observing from the ground is basically impossible).
Meanwhile, problems to be solved during the 1994 repair mission are mounting steadily. Apart from the installation of the corrective mirror package, 2-3 of the gyros need changing (and there is some worry whether the remaining 3 will last until the repair, although the telescope could be held in a safe attitude for the repair without them), the solar arrays need replacing because of the flapping problem (although recent analysis indicates that fears of structural failure before then were exaggerated), and something has to be done about the high-resolution spectrometer's ailing power supply (although it's not yet clear what).
Galileo Gaspra encounter imminent. Small corrections to the course were made Oct 9 and Oct 24 in preparation for the Oct 29 encounter.
Engineers still studying Galileo's antenna problem. The current best guess is that 4-8 cooling/heating cycles should work it loose. This does cost fuel, with each cooling turn eating about 4kg. Under reasonably conservative rules, Galileo's current fuel margin for a full Jupiter mission and the asteroid Ida is zero. Eliminating the Ida encounter would save 35kg. NASA will decide in July whether to fly the Ida encounter, and whether the antenna is free will be a major consideration.
Galileo can still drop its probe into Jupiter and relay the data back without its high-gain antenna, and that is one of its major mission objectives, so nothing risky will be tried until that is over. There will be a de-facto experiment in applying extra force to the antenna during Jupiter orbit injection, however, with Galileo's big maneuvering engine firing and the spacecraft spun up to 10RPM instead of its normal 3RPM.
Rep George Brown introduces bill to make sweeping changes to Landsat, offering cheap data to nonprofits, expediting Landsat 7, and directing NASA and DoD to manage the proggram jointly. The original attempt to privatize Landsat envisioned gradual reduction of subsidies, but "what we experienced instead was an annual struggle to get *any* Landsat funding", and as a result it didn't work too well. Moreover, most of the government agencies (the big customers) like the data, but not enough to want to fund or manage the program. DoD is the exception, in the wake of the Gulf War, but civil involvement is thought desirable to avoid restrictions on data access, hence the NASA involvement in Brown's bill. The bill tells NASA to buy Landsat 7 from Eosat, and specifies that it be a copy of 6 with one advanced instrument (e.g. a 5m-resolution stereo sensor) if this will not threaten a 1997 launch. Brown notes that various people are studying using arrays of smaller satellites instead, but the GOES-Next fiasco shows what happens when you scrap today's hardware before tomorrow's is ready. [A lesson that a lot of the space decision-makers need to learn.]
Arianespace begins marketing of Ariane 5 for commercial customers, including issuing the first edition of the users' manual. Various nominal missions are envisioned, including triple payloads and tricks like leaving one in low orbit and taking the other two into transfer orbit.
European defence ministries discuss a joint military comsat system for Western Europe.
France decides to modify the military relay packages on its future civil comsats to permit processed images from its Helios spysat to be relayed to field commanders, saying that Gulf War experience indicates that the US had considerable trouble getting images out into the field promptly. Officials say that the satellite hardware won't need much in the way of changes, although the ground end will need more work.
NASA Cape managers to meet Nov 8 to decide whether Endeavour can be kept on schedule for its late-spring launch. It is currently thought to be 1-2 months behind schedule due to a long list of minor problems, mostly ones that were recognized before its move to the Cape. More will undoubtedly surface; both Columbia and Discovery had long lists of problems during preparations for their first post-Challenger launches. The question right now is how much overtime is going to be needed, with NASA under heavy pressure to cut shuttle operations costs. (There is talk of mothballing one of the two KSC launch pads to reduce workload.) Many of the open problems could have been eliminated if Endeavour had stayed at Rockwell a bit longer. It was moved early to save money, but in fact the saving was minor and Endeavour ended up $200M under budget. The Cape management blames a lot of the problems on having Endeavour's pieces constantly "borrowed" when the flying orbiters needed spare parts.
Long article on "pulsed detonation engines", the high-tech version of the pulsejet. Analytical techniques are now up to handling unsteady combustion, and interest in such engines has revived. They can, in principle, be substantially lighter than jets and rockets, operate over wide speed ranges either as air-breathers or as rockets, and be mechanically simple. The NASP people are obviously paying attention, and there is speculation that they may be seriously considering such an engine. There is also considerable speculation that at least one highly-classified aircraft may already be flying with such an engine, since it fits the characteristics of some odd sightings.
Trimble Navigation seizes an opportunity on its doorstep, sending volunteers with Navstar receivers to help fight the Oakland-Berkeley hills fire. One receiver was flown around the perimeter of the fire while recording locations, with a map of the current state of the fire printed out via a laptop five minutes after the helicopter landed. After the fire was out, damage assessment was also speeded up by using a receiver for precision mapping of the burn area, a rough hilly region where existing maps were inadequate.
SVR4: proving that quantity is | Henry Spencer @ U of Toronto Zoology not a substitute for quality. | henry@zoo.toronto.edu utzoo!henry