Date: Fri, 19 Mar 93 05:48:21 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #340 To: Space Digest Readers Precedence: bulk Space Digest Fri, 19 Mar 93 Volume 16 : Issue 340 Today's Topics: How to cool Venus Luddites in space moon's fate when removing gravitational influence of earth (2 msgs) plans, and absence thereof Russians ICBMs -> SLVs SR-71 Maiden Science Flight Why use AC at 20kHz for SSF Power? Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: Fri, 19 Mar 1993 06:12:57 GMT From: Michael Moroney Subject: How to cool Venus Newsgroups: sci.space schumach@convex.com (Richard A. Schumacher) writes: >In <1993Mar18.082941.10534@nic.funet.fi> TMakinen writes: >Err, all that carbonate rock was created by life: corals, diatoms, >etc., make calcium carbonate for their shells, spicules, and whatnot. Much of it was. Much was formed by another process, the weathering of silicate rocks. An example of this process is basically XSiO3 + CO2 -> XCO3 + SiO2 (sand). This process does not depend on life. -Mike ------------------------------ Date: 19 Mar 93 08:40:53 GMT From: Nick Szabo Subject: Luddites in space Newsgroups: sci.space,talk.politics.space mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes: >I prefer sending people to sending toasters. Typical Luddite comment. The $billions in technology are merely toasters, the engineers and techs who make them merely toaster-makers, and the only people that count are the people who have accomplished almost nothing for the space program, the astronauts. -- Nick Szabo szabo@techboook.com ------------------------------ Date: Fri, 19 Mar 1993 06:06:45 GMT From: Leigh Palmer Subject: moon's fate when removing gravitational influence of earth Newsgroups: sci.space In article Michael Moroney, moroney@world.std.com writes: >Its orbit might be more eccentric than earth, depending on where >it was relative to earth at the time earth "vanished". Its orbit would be more eccentric than that of the Earth regardless of where it was when the Earth "vanished". First, let's adopt a physically conceivable process for the disappearance of the Earth. My idea of a good one is to have the Earth explode neatly into northern and southern hemispheres, the two pieces recoiling with, say, half the velocity of light. That's better than having the Earth "vanish", and I think it retains the spirit of the question. If the Earth explodes at full moon, the speed of the moon will be greater than Earth's orbital speed, and the moon's subsequent orbit will be eccentric with perihelion at the point of the explosion. If the explosion occurs at new moon then the speed of the moon will be less than Earth's orbital speed and the resulting eccentric orbit will have its aphelion at the point of the explosion. The only way the moon could have an Earth-like orbit after the explosion would be if it had Earth-orbital velocity at the time of explosion. We've just examined the two cases for which the direction would be correct, and neither has nearly the correct speed. Thus the resulting orbit must be eccentric. QED Leigh ------------------------------ Date: Fri, 19 Mar 1993 06:51:10 GMT From: Henry Spencer Subject: moon's fate when removing gravitational influence of earth Newsgroups: sci.space In article <1993Mar19.060645.20605@sfu.ca> Leigh Palmer writes: >... The only way the moon could have an >Earth-like orbit after the explosion would be if it had Earth-orbital >velocity at the time of explosion. We've just examined the two cases for >which the direction would be correct, and neither has nearly the correct >speed. Thus the resulting orbit must be eccentric. Note that the Earth's already is. Not a lot, but some. And since the Moon's orbital velocity around the Earth is about 1 km/s, and the Earth/Moon orbital velocity around the Sun is about 30 km/s, the Moon's resulting orbit wouldn't be massively eccentric. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 19 Mar 93 09:07:11 GMT From: Nick Szabo Subject: plans, and absence thereof Newsgroups: sci.space,alt.sci.planetary prb@access.digex.com (Pat) writes: >JPL A) Has their plate pretty full doing existing missions. Quite the opposite, they are laying people off and rapidly revamping their strategies in search of new missions. It's a time of flux at JPL, a time for it to incorporate new strategies and visions to take advantage of the new technology and knowledge we have going into the 21st century. > B) is oriented to certain mission types, and prospecting > is a little out of their balliwick.. JPL, Caltech, and universties that work closely with it such as U. of Arizona, are chuck full of planetary scientist/geologists. There are dozens of quite talented planetary geologists who work in the oil and mining industries. JPL and the planetary science community have some growth and adaptation to do, to emphasize these types, but there's nothing to prevent it from growing this way, it's a natural direction. JPL has also done work in microgravity processing, and could neatly tie these two skills together, as most microgravity processes don't become economical until we can start tapping the abudant native materials in space, instead of launching all the raw materials from earth. Cost is highly dependent on ore quality, ie the results of solar system prospecting. There are many other aspects besides geology that also could be interesting; eg the processing of large-scale plasmas in space borrows directly from the current biggest application of space science, the study of the near-earth space plasma environment and its implications for satellite design. >get basic operating costs in space down by 2 orders of magnitude. >Then the market will do the rest. But right now planetary science is operating without any feedback from markets, real or potential. That's why we haven't flown a lunar orbiter -- there's not much basic science for it to do, but it is one of the top-priority projects from a future-market prospecting point of view. Planetary science and the associated native materials processing plays a central role in dropping costs by orders of magnitude, leapfrogging the very slow trend in launch cost reduction since the 1960's by opening up sources of industrial supply off earth. I'd point out that other parts of government scientific research suffer from this rot, SSC being the most expensive, glaring example. (The astronaut program would also be an example but most scientists have by now disowned it). -- Nick Szabo szabo@techboook.com ------------------------------ Date: 18 Mar 93 21:16:56 From: David.Anderman@ofa123.fidonet.org Subject: Russians ICBMs -> SLVs Newsgroups: sci.space Are any details on the design of former Soviet ICBMs available now? --- Maximus 2.01wb ------------------------------ Date: 19 Mar 93 06:28:50 GMT From: Dean Adams Subject: SR-71 Maiden Science Flight Newsgroups: sci.space prb@access.digex.com (Pat) writes: >Wouldn't some of the Dryden Pilots for the NASA SR-71 now have been >former AirFOrce Recon Pilots? They are NASA pilots. >I imagine it's just cheaper to get them on TDY or Assignment to >NASA then to send people through SR-71 flight school. I expect the AF pilots had their own ideas for their careers. :-> >Actually, I once saw a picture of a two seat SR-71 Pilot trainer. >If that was de-commisioned, it will be hard to train new SR-71 pilots. Which is exactly why the SR-71B/#956 (NASA 831), is now living at Dryden. ------------------------------ Date: Fri, 19 Mar 1993 05:46:59 GMT From: "Richard A. Schumacher" Subject: Why use AC at 20kHz for SSF Power? Newsgroups: sci.space Oh, nuts. So a 20kHz power system saves 2,000 pounds, huh? Assume it costs $3,000 per pound to launch. Spend $6M on the extra weight of a 400 Hz system, and 20 minutes later you're in orbit. Instead, NASA spent $20M and two years on 20 kHz system development, and has a lot of paper sitting on desks. As for the difficulty of shielding scientific instruments from 400 Hz noise: some EE better go tell those poor fool astronomers who have been flying their instruments in U-2s for 20 years that they're doing it all wrong... (Oh no! Now they're doing the same thing in an SR-71! Stop them before it's too late!) 20kHz power is a Boondoggle. A gold-plated, aerospace- contractor's-wetdream, engineering-porkbarrel boondoggle. ------------------------------ End of Space Digest Volume 16 : Issue 340 ------------------------------