henry@utzoo.uucp (Henry Spencer) (10/10/89)
Cover story is, of course, Voyager at Neptune. Editorial observes that the entire Voyager project has cost about $865M. "...the world and the international scientific community... owe the Voyager team every accolade -- not only for their achievements, but also for reminding us that lack of imagination and resolve put greater limits on humanity's grasp than lack of resources." Voyager sees many things, including cloud shadows on Neptune. [As before, I am keeping Voyager coverage light since more timely sources have done it already.] Satellite N1 is now the second-largest moon in the Neptunian system, somewhat larger than Nereid; it would have been seen from Earth long ago except that it is in a very low orbit quite close to Neptune, while Nereid is much farther out and easier to notice. Third operational Navstar launched on Delta Aug 18, after three weather delays. Soviets looking at planetary missions to Mercury, Venus, and Phobos as part of a somewhat-revised planetary program. The Phobos mission would include a sample return. Manned Mars missions have gone on the back burner due to cost and difficulty; equipment reliability and human factors are seen as the significant problems with such a project. The Phobos spacecraft bus, with modifications to increase reliability, will remain the major spacecraft, and Proton the major launcher (Energia was not mentioned). The Soviets are looking seriously at surface missions with several small landers or penetrators rather than one fancy one, adding redundancy and widening coverage. Current plans are: 1996 Phobos sample return, essentially a rerun of the 1988 mission with soil-analysis instruments replaced by the return vehicle. An attempt will be made to get subsurface samples, either with a penetrator that is reeled back in or by drilling after landing. 1998 Venus mission with 6-8 penetrators to examine surface chemical composition in a variety of terrains. 2002-3 Mercury mission, orbiter plus either several penetrators (including cameras) or a soft-lander. Proton launch would require a Venus gravity assist. Mercury's geology is odd, with much more of its mass in its core than is usual for inner planets, and geology will be the focus of the mission. Soviets simplifying 1994 Mars mission to stay on schedule. Each spacecraft will be an orbiter, a balloon, and several small "surface stations". The major change is use of a small off-the-shelf reentry craft rather than a large new one, which would require considerable testing. This dictates splitting up the original large lander. The surface stations might be either penetrators or soft-landers. France, which is taking a significant role in the 1994 mission, is concerned that the mission is still changing and still not firmly committed to launch. Letter from Al Globus observing that calling for a fifth (sixth, seventh, etc.) orbiter is the wrong approach: as long as there is no commitment to replace the shuttle with something else, what is needed is a commitment to continuous orbiter production. Letter from G. Brachet, chairman of Spot Image, saying that AW&ST was wrong to claim that most Spot sales, and sales growth, involves government customers. This has been true in the past, especially in the US, but is no longer true overall and is less true now even in the US. -- 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