Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Thu, 8 Feb 90 01:27:15 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 8 Feb 90 01:26:46 -0500 (EST) Subject: SPACE Digest V11 #16 SPACE Digest Volume 11 : Issue 16 Today's Topics: Re: More Info On SSX Re: Galileo Update - 02/06/90 (Forwarded) ---------------------------------------------------------------------- Date: 7 Feb 90 06:44:47 GMT From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: More Info On SSX In article <21900066@m.cs.uiuc.edu> carroll@m.cs.uiuc.edu writes: >a useful payload of 9000 to 20,000 lb... >each vehicle is around $30 million, yielding launch costs >of about $50 per pound of payload in Low Earth Orbit. >/* End of text from m.cs.uiuc.edu:sci.space */ >Forgive my math, but I get >$30,000,000 / 20,000 lb = $1500/lb, not $50. SSX is not an expendable! By the same reasoning, the cost of flying Toronto-LA in a 747 is $120M / ~500 = $240,000 per ticket. I made that trip once, and I don't recall it costing quite that much... -- SVR4: every feature you ever | Henry Spencer at U of Toronto Zoology wanted, and plenty you didn't.| uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: Wed, 07 Feb 90 11:48:00 -0900 Sender: Reply-To: From: "jason" signoff space digest ------------------------------ Date: 7 Feb 90 20:14:46 GMT From: sunlight!loren@lll-winken.llnl.gov (Loren Petrich) Subject: Re: Galileo Update - 02/06/90 (Forwarded) In article <1990Feb7.171046.23652@ux1.cso.uiuc.edu> wehmer@aries.scs.uiuc.edu (James Wehmer) writes: >> NASA's Galileo spacecraft will fly by planet Venus at about >>1 a.m. EST, Sat., Feb. 10, 1990, on the first leg of its gravity- >>assisted flight path to planet Jupiter. Galileo will record >>scientific observations for playback in October. There will be >>no live or real-time science from this Venus fly-by. >> > Why wait eight months to download the Venus data? > Is the Galileo mission schedual too busy to allow an earlier playback? > > Thanks, I was just wonderning. There is a long story behind that. Originally, the craft was scheduled to go directly to Jupiter. But then NASA decided that the original booster, the Centaur, was too dangerous to travel in the Shuttle's cargo bay, because of its liquid fuel. So they substituted a less powerful solid-fuel booster, which was not quite powerful enough to propel Galileo to Jupiter directly. Some clever hacker devised the VEEGA (Venus-Earth-Earth-Gravity-Assist) trajectory. Galileo would fly by Venus once, then the Earth twice, getting enough energy from these encounters to make it all the way to Jupiter. However, it was not designed to get too close to the Sun; they had to install some insulation, and they have to keep the main antenna closed, or else it would disintegrate. So that is why they will be waiting nine months to get back the Venus data. The main antenna is being kept closed for its protection, and the only antenna(s) functioning now have too low power/bit-rate to be useful for sending back the data now. So we will get the data when the craft is much closer to the Earth. Here's the schedule: The Venus encounter is in the next couple of days. The first Earth encounter is December of this year. The second Earth encounter is December of 1992. The arrival at Jupiter is December of 1994. This is the best I could remember. ^ Loren Petrich, the Master Blaster \ ^ / loren@moonzappa.llnl.gov \ ^ / One may need to route through any of: \^/ sunlight.llnl.gov <<<<<<<<+>>>>>>>> lll-lcc.llnl.gov /v\ lll-crg.llnl.gov / v \ star.stanford.edu / v \ v "I'm just a spud boy looking for that real tomato" -- Devo ------------------------------ End of SPACE Digest V11 #16 *******************