al@ames-lm.UUCP (01/31/84)
There has been a great deal of hand ringing over the lack of new starts in the planetary program. Prepare thyself for heracy, I think the lack of new starts is a good thing, although it should end in a year or two. Why? Well, when conducting science I believe that it is a good idea to understand the results of your first experiment before charging off on a second. The planetary community should take a good hard look at the Voyager data before designing the next set of planetary missions, at least to the planets we've already visited. This argument is not valid for asteroids and comets of course.
flinn@seismo.UUCP (E. A. Flinn) (02/01/84)
Al Globus (NASA Ames Research Center) recently wrote: > "There has been a great deal of hand ringing over the lack of new >starts in the planetary program. Prepare thyself for heracy, I >think the lack of new starts is a good thing, although it should >end in a year or two. Why? > "Well, when conducting science I believe that it is a good idea to >understand the results of your first experiment before charging >off on a second. The planetary community should take a good hard >look at the Voyager data before designing the next set of planetary >missions, at least to the planets we've already visited. This argument >is not valid for asteroids and comets of course." If planetary science were actually 'charging off' to acquire new data before understanding what is already on hand, and if total understanding of, say, the Voyager data were a prerequisite for designing subsequent missions to whatever planet, this argument might have some validity. However, this is not the case. It takes many years to process and analyze the data from any planetary mission, and it takes at least *ten* years between the time that the planetary science community comes to what can pass for agreement on what the priorities are and what mission should be attempted next, and the approval of that mission - and then another five to seven years before launch and another two in flight - making roughly half a generation between our realizing that it's desirable to do a Galileo, say, and actually getting the data in hand. OMB does its best to apply Globus's argument, but planetary scientists obviously need more than one mission per career, and the solar system contains a sufficient variety of objects that we can be planning one or more missions while previously approved missions are still under construction or in flight. A few words to bring readers up to date on what the status of planetary missions actually is. Galileo is on track for launch in 1986 and arrival in 1988-89. Things look reasonably good for the forthcoming Voyager encounter. The Venus Radar Mission was approved in the FY1984 budget. The FY1985 budget announced by the President today includes a Mars Geoscience/Planetology Orbiter, the first of a series of Planetary Observer missions. ISEE has been renamed the International Comet Explorer, and is headed for Giacobini-Zinner after completing a a successful lunar flyby. The next mission for which the Solar System Exploration Division at NASA Headquarters will seek approval is the Comet Rendezvous - Asteroid Flyby, the first Mariner Mark-II mission, which will rendezvous with Comet Kopff and do a flyby near asteroids yet to be selected. The next highest priority mission after that will be a Titan Probe - Radar Mapping mission to Titan. I will certainly add 'hand ringing' and 'heracy' to the list of NASA jargon. -- Ted Flinn (former Deputy Director of Planetary Programs, NASA Headquarters)
al@ames-lm.UUCP (Al Globus) (02/03/84)
If I read Ted Flinn's argument right, one should plan a second experiment (in this case a planetary probe) before really understanding the first because it takes 15 to 17 years to fly a space craft. Maybe the real answer is to cut that time down to something reasonable, say 3-5 years. The 15-17 years was broken down into 10 years of milling about and 5-7 years of work. I don't know what to do about the milling about, we certainly do a great deal of that here (I must admit I've contributed by share); but it seems to me that it should be possible to speed design and implementation, since we've already built several deep space probes and presumably learned enough to speed the process. There is another approach to getting more missions without designing new probes before examining the data from old ones. There are a lot of objects in the solar system, nine planets, our moon, several other moons, comets and asteroids. While Jupiter may be more glamorous, good science could be done with Lunar, cometary, and asteroidal probes. The moon hasn't had much attention since Apollo and the comets and asteroids have never been visited. Doesn't it make sense to go out there and take a look? Actually, things have worked out so that there has been time to examine the data. Galileo has been delayed enough to incorporate Voyager results and the Mars new start comes several years since the last probe to Mars. The planetary program proposed by that NASA committee (I can't remember the name) seems balanced and sensible. What I do object to are those that claim that the U.S. space program is falling apart. Nothing could be further from the truth. The program is strong, vigorous, well funded and has mainained a continuous stream of accomplishment from Mercury, Gemini, Apollo, Viking, Voyager, Skylab, IRAS, shuttle, spacelab and on to space telescope, Galileo, and space station. My other pet peeve are space scientist trying to sabotage manned programs such as space station. It we had a space station, Solar Max would have been fixed years ago, IRAS could be 'refueled' with coolant and work for years instead of months, and we could accumulate instruments in orbit instead of using them for a few months or years and then abandoning them for lack of simple repairs and resupply. This sort of accumulation could dramatically lower the cost of doing space science and open the field to far more researchers. In addition, many important space science projects requiring very large structures are impossible without a space station. Well, I'll get off my high horse. Bye.