henry@utzoo.uucp (Henry Spencer) (10/23/89)
[Yes, I'm running a bit behind again...] National Space Council is deep in the process of preparing a recommendation to Bush on how to proceed with the Moon/Mars strategy he proposed. Lots more Voyager pictures. Closest encounter with Neptune was 3 miles high and 21 miles to the right of the intended point, and arrival was one second behind schedule. The science crew originally wanted to fly closer, to get a closer Triton encounter, but the engineering crew got nervous about Neptune's little-known atmosphere and insisted on a 3000-mile minimum. Triton has shrunk :-) -- pre-encounter estimates gave its diameter as perhaps 2500 mi, now revised to 1690. The surface is brighter than expected. A thin atmosphere was seen. The back look at Neptune's rings shows clearly that the three major rings are indeed continuous, if perhaps lumpy, and there is also a broad sheath of diffuse material. Dust impacts started 2 hours before ring- plane crossing (much earlier than expected) and continued 2 hours after. The 20-30 minutes bracketing the crossing had impacts comparable to the level seen at Saturn, about 300 (very small) particles per second. NASA acknowledges help from USAF during Neptune encounter -- the USAF had planned to briefly shut down the Navstar network in late August, but agreed to keep it running because the Deep Space Network uses it for coordinating timekeeping. Voyager officials are discussing using Voyager's imaging system once more, for a series of shots of the planets from outside the ecliptic. This would be done in March or April, when the planets are in good positions for it. The Voyager Interstellar Mission begins in October. This will involve daily tracking and data collection from field and particle instruments. The imaging system and related equipment will be shut down in 1990 to eliminate their power consumption. Galileo final checkout begins, including handling tests with dummy RTGs to verify installation procedures. Second launch attempt for Japan's GMS-4 Clarke-orbit metsat set for Sept 6. The H-1 booster got as far as main engine start on Aug 8 and then shut down when a valve in the vernier-engine system malfunctioned. [The long postponement is because tracking and communications resources are committed to Voyager for the rest of August.] Japan announces plans for a new small solid launcher, the M-5, for science missions. First sort-of-completely-private US satellite launch, as a commercial Delta carries Marcopolo 1, a British broadcast satellite, up Aug 27 from the Cape. This was the launch that was originally going to carry Insat, whose launch has slipped to next year due to the need to replace its C-band antenna, totalled when a crane hook hit it. The only government presence in the launch was USAF crews handling tracking and range safety. Amusingly, McDonnell-Douglas found it had to buy fuel from Japan at $30/gal, because the old engine variant used on this launch wants a fuel mix that is no longer made in the US. The launch is noteworthy in that Hughes, the satellite builder, covers all risks of launch failure, with the contract stipulating payment only for an operational satellite in orbit. (This is increasingly standard procedure, and Hughes has signed similar contracts with other customers since.) Formal report on the Insat damage is complete. Basically, it was a freak accident. One of the two cables on the hook came out of its groove, and lowering the hook in that condition caused the two cables to saw across each other and break. The problem occurred near the top of the launch tower, and the technicians operating the crane could not see it because of the debris shield attached to the hook. Soviet Union to resume manned activity on Mir. The first add-on module will fly in October [this has slipped due to malfunctioning electronics in the module]; it will be a service unit containing more gyros, a water-decomposition oxygen system, a shower, and a large airlock with a manned maneuvering unit for EVAs. A second module, slated for launch in Jan-Feb, will be a "technological unit". The second module is reported to be equipped with a docking port for Buran, tentatively scheduled to be used on Buran's next flight in 1991. The flight will be unmanned at launch, but there is some possibility that Mir crewmen might go along on the return trip. [Pico-editorial: Remember all the news media that were hinting that the Soviet space program was being drastically cut back, when Mir went unmanned? How many of them have even bothered to report that a new crew has now gone up?] Hipparcos is definitively stuck in transfer orbit, and ESA is working on salvaging what it can. The apogee motor is definitely not going to fire. Lifetime is estimated at 6-18 months, as against the 30 originally planned. As much as possible of Hipparcos's star-mapping mission will be performed. The limiting factor will probably be Van-Allen-belt damage to the solar arrays; the extent of the problem is not yet confidently known, although there is some optimism because little degradation has been seen so far. Hipparcos was not insured, although Matra (the builder) has lost half its profit under the terms of the contract. ESA has asked for a quote on a Hipparcos 2; initial guesses are $150M including bird, launch, and support. TVSat 2, the other cargo on Hipparcos's launch, is in Clarke orbit and about to begin operations. Picture of Amroc's first launcher in position at Vandenberg. Timetable for the SP-100 space reactor has slipped several years due to recent funding shortages. Ground demo of the reactor, originally 1991, is now 1994. Ground demo of the complete system, originally 1994, is now in limbo. Letter from Thomas J Frieling, suggesting what JFK's commitment to Apollo would sound like if George Bush were delivering it today: "I believe this nation should commit itself to achieving the goal sometime in the near future, or maybe the more distant future, of landing a man on the Moon and returning him safely to the Earth. No single space project in this period, and I'm not sure how long a period we're talking about here, will be more exciting, or more impressive to mankind, or more important for the long-range exploration of space; and none will be so difficult or expensive to accomplish, although I don't know exatly how expensive since I'm not asking Congress to actually fund these missions." Frieling concludes: "Is this leadership, or what?". [The 22 July issue of Flight International had a very interesting map: possible NASP test routes, for gradually increasing speeds. The slowest one goes from Edwards to KSC and back: cruising on the way out, making a tight turn around KSC, accelerating until about the Texas border, and gliding back to Edwards. The next one swings northwest after the KSC turn, accelerating until about Montana, making a 90-degree turn just after shutdown and gliding back to Edwards. The next cruises from Edwards to Loring AFB in Maine, turns around Loring and accelerates west until about the Washington border, and glides back to Edwards in a big semicircle swinging out over the Pacific. The last one accelerates east from Edwards to about Bermuda and then starts a left turn. If the engine fails at that point, it glides in a semicircle to land at Loring. If the engine keeps running, it makes a wider semicircle to make landfall in Canada, shuts the engine down around Lake Superior, and glides back to Edwards. The objective is to keep the thing over land, or at least within glide range, as much as possible. "We'd hate to lose it at sea."] [The 29 July Flight has a couple of interesting items. First, an editorial on the 40th anniversary of jet airliners (the de Havilland Comet, the first, flew 27 July 1949), which has a lot to say about spaceflight. "The lack of confidence in technology stretches into space, where good ideas are the only things guaranteed to fly. The British have orphaned Hotol, the Europeans have emasculated Hermes, the Americans seem uncertain whether they should have either a Space Station or the shuttle to service it... Even President Bush, with his bold announcement of a permanent American presence in space, of a renewed interest in the Moon and a mission to Mars, seems to hold no truck with this as a vehicle of technical or social progress. Rather, the space effort's renewal seems to be driven by a need to be seen to be doing something, not the need to be doing something itself. That forms a shaky platform for a programme, even before the politicians focus their inevitable hostility on it. This is not a culture of progress, but a culture of fear of being left behind by others' progress. Such a culture has an aura of doom about it... To look back 40 years with pride to the first flight of the Comet is not just to indulge in irrelevant nostalgia. It is to look back to the start of a great industrial revolution which, almost staggeringly, has matured within the lifespans of most of those who gave birth to it. Most of all, it is to look back and wonder whether we have really progressed in moving from the 1949 of 'Can do' to the 1989 of 'Why do?'." Second, more mundanely -- why didn't this show up in AW&ST?!? -- is a report that first flight of Japan's H-2 booster will slip a year from the planned date in early 1992. The main engine is having trouble with valves and with cracks in turbopump blades, and some component redesign will be needed.] [Sounds like their decision to use the same engine cycle as the Shuttle is giving them some of the same problems...] -- A bit of tolerance is worth a | Henry Spencer at U of Toronto Zoology megabyte of flaming. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu