henry@utzoo.uucp (Henry Spencer) (11/27/89)
[Yes, you read that correctly -- "part 1". This is a planetary-missions issue, with lots of coverage in anticipation of the Galileo launch, so I'm doing it in (at least) two parts.] The cover is an artist's conception of Galileo approaching Jupiter. Security at KSC tightened for the Galileo launch, against the possibility of the Christics et al attempting disruptive tactics. Hubble telescope smuggled from Lockheed Sunnyvale to KSC Oct 4, using a USAF C-5 modified for heavy spysats. NASA wanted to make it a public event, but the USAF said the shape of the shipping container used -- the same one that will be used for a new large imaging spysat -- is secret! One NASA manager comments that "it doesn't take a rocket scientist" to figure out that the new spysat must be shaped rather like the Hubble telescope... Initial NASA assessments indicate that using the space station as a staging base for lunar operations would have "a significant impact". The estimated cost of design changes is about $1G; they would include more power, more heat radiators, upgrades to life support to handle 14-16 astronauts temporarily, and construction of the lower part of the old "dual keel" design to accommodate docking facilities for Shuttle-C and a servicing facility for a lunar transfer vehicle. The extra hardware would have to go up pretty much immediately on completion of the basic station if lunar activity starts on the schedules some are projecting, circa 2000. There is debate about whether using the same platform for lunar operations and microgravity research is really a good idea. ESA is uneasy about whether lunar support will divert NASA attention and money away from research work. Lenoir says NASA has rather mixed feelings about simultaneous requests to save money on the space station and to expand it to support lunar exploration; he says one or the other will have to give. Amateur astronomers report that the spysat launched in summer by Columbia is tumbling rapidly, circa 30 RPM, suggesting that it is out of control. "Intelligence community" sources say that although the bird had problems initially, it is now functioning normally. [More recently, it has apparently maneuvered, lending support to this.] To add to the mystery, apparently Columbia deployed *two* satellites on that mission; outside analysts think the big one was an uprated KH-11 optical spysat, but nobody has any ideas about the other one. First Amroc launch attempt fails Oct 5 with a fire destroying much of the vehicle on the pad at Vandenberg. Hipparcos's scientific mission is underway, everything working fine despite the undesired orbit. Analysis of Voyager 2 images turns up a geyser-like volcanic (?) plume on Triton, with a cloud drifting 90mi downwind. [Lots of coverage of US planetary-mission plans, much of it fairly familiar. I will just hit high spots...] A graph of US scientific launch activity in the last 30 years is somewhat striking. From 1958 to 1978, the longest gap between major exploration missions was one year. Between Pioneer Venus in 1978 and Magellan this May... nothing. JPL will start CRAF/Cassini construction work in 1991, the first major spacecraft start at JPL since Galileo over a decade ago. There is some concern about the loss of crucial skills in the hiatus. Galileo launch prepations include four heavy transports standing by at KSC with emergency teams. One is fairly mundane, an orbiter-return team in case of an emergency landing downrange. The others are a little less common: a two-aircraft team with cooling equipment to deal with Galileo's RTGs in the event of an emergency landing, and a DOE radiation-spill team in case of a crash. Atlantis will carry an assortment of small experiments along with Galileo. The only one of note is a gravity-gradient experiment, to assess whether the orbiter's attitude can be stabilized simply by positioning it with nose toward Earth and one wing facing into the direction of flight. This could save fuel for later long-duration flights. Galileo will attempt various experiments during its Earth encounters. Plans are not yet fixed, but among the ideas are: - A high-speed movie of the Earth approach, starting from 20Mmi with Earth as a small crescent and moving in to encounter (with a resolution of 50ft or so). The two encounters will pass over Egypt and South Africa respectively. - Detailed examination of the Moon with modern instruments. About 2/3 of the Moon has not been seen well for two decades. Galileo will get good views of areas that have never been mapped at high resolution. - Examine lunar polar craters for evidence of frozen volatiles. Galileo's instruments are not ideal for this but could give some information. - Look for evidence of the swarms of mini-comets that some think contribute a significant amount of water to Earth. Lunar impacts should result in a considerable cloud of hydrogen around the Earth-Moon system, which could be detectable from deep space. - Use Galileo's dust detector to look for a "dust belt" in the vicinity of Earth's orbit; one theory holds that dust falling inward towards the Sun from the asteroid belt could be delayed near Earth, forming a thin belt. Galileo's second asteroid encounter is probably off the agenda unless cruise fuel consumption is significantly lower than predicted. Even the first encounter will be endangered if consumption is worse than expected. Nothing will be decided until after Venus encounter in Feb. -- That's not a joke, that's | Henry Spencer at U of Toronto Zoology NASA. -Nick Szabo | uunet!attcan!utzoo!henry henry@zoo.toronto.edu