Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from holmes.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests) ID ; Wed, 3 May 89 05:17:07 -0400 (EDT) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 3 May 89 05:16:55 -0400 (EDT) Subject: SPACE Digest V9 #406 SPACE Digest Volume 9 : Issue 406 Today's Topics: Re: Smart Pebbles Magellan update Re: Earth based - will it always win? Re: wireless electricity Re: Censorship ( was Space Shuttle Attacked by 200-foot UFO!) Re: Near miss Re: Earth based - will it always win? Re: Smart Pebbles Magellan update update Re: Smart Pebbles Final Frontier June 1989....EXCELLENT ISSUE ---------------------------------------------------------------------- Date: 1 May 89 10:47:16 GMT From: blake!sealion@beaver.cs.washington.edu (sealion) Subject: Re: Smart Pebbles In article <1989Apr28.151108.15074@cs.rochester.edu>, yamauchi@cs.rochester.edu (Brian Yamauchi) writes: > In article <3761@aplcomm.jhuapl.edu> jwm@aplvax.jhuapl.edu (Jim Meritt) writes: > > > >See the film footage of the test of the smart pebble? > > > >That looked _NEAT_!!!!! That thing sitting there bursting its jets holding > >a hover was slick!!! > > Yeah, it looked really neat. Just one question: What's the difference > between the smart pebble concept and placing smart interceptor > missiles in orbit? The film shows the first full-bore laboratory test of what is sometimes referred to as a "smart bullet". The space based weapon is designed to eliminate it's target (ICBMs) through high speed collision during the boost and mid-course phases of flight. No warhead needed. The same concept as a bullet. Simply a kinetic weapon. Very effective. Eventually, the size of the weapon is supposed to be reduced to that of a basketball with a weight of about 15 lbs. Thus the name "Brilliant Pebbles". ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence." || - Jeremy S. Anderson 12/15/88 #include sealion@blake.acs.washington.edu ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ------------------------------ Date: Mon, 1 May 89 15:03:57 PST From: Peter Scott Subject: Magellan update X-Vms-Mail-To: EXOS%"space@andrew.cmu.edu" This is most of the text of a recorded announcement made available to JPL employees: This is the JPL broadcast news service prepared at 2pm PDT, Sunday April 30. Since Friday's launch attempt the Magellan spacecraft and the attached IUS booster have remained in the payload bay of Atlantis. The payload's state of health is being monitored by telemetry and the trickle charge has been reestablished on the flight batteries aboard Magellan. Control of the payload continues to be via the Magellan ground station and the IUS checkout station which are located at the Kennedy Space Center. The Magellan receiver lockup observed after the MYLAR [?] tracking station switched to high power shortly before launch received troubleshooting yesterday. There was no damage to the receiver as a result of the occurrence, however, while Magellan's computer is designed to preclude receiving inadvertent commands, there was a reverification of the spacecraft onboard computer software Friday night. Yesterday propellants were offloaded from Atlantis' external tank and the rotating service structure was moved back in place back around the vehicle. Workers have opened up the orbiter's aft compartment and are removing insulation from the liquid hydrogen pump recirculation package. Engineers are planning to conduct checks of the pump power lines and replace at least one of the pumps tonight. Tomorrow checks of the new pump will begin. These pumps circulate liquid hydrogen to the main engines and condition them prior to starting these engines. The 3 pumps are contained as a package in the orbiter's aft compartment and each is about the size of a softball. Scaffolding has been erected on the pad to gain access to the exterior four inch liquid hydrogen recirculation line between the orbiter and the external tank. Managers decided to replace the line because of vapors seen escaping minutes after the launch scrub. The vapors indicate the presence of a pinhole in the seal. Workers are removing insulation around the line today and are scheduled to remove the line late tonight. Tomorrow the new line will be installed and secured in place. STS-30 pilot Donald Walker and commander David Grabe left the Kennedy Space Center today for Houston today. The 3 mission specialists left yesterday. The whole crew will practice in the shuttle simulator in Houston during the next few days. [Launch has been rescheduled for Thursday since this recording.] Peter Scott (pjs@grouch.jpl.nasa.gov) ------------------------------ Date: 1 May 89 19:12:01 GMT From: cfa!cfa250!willner@husc6.harvard.edu (Steve Willner P-316 x57123) Subject: Re: Earth based - will it always win? From article <14295@bfmny0.UUCP>, by tneff@bfmny0.UUCP (Tom Neff): > All of which brings me to a question I've often wondered about. Given > enough time and ingenuity can't we nearly always do better here on > Earth? Yes, we are crushed by 1G and swamped in a gaseous muck that > blocks some wavelengths and distorts most of the rest. [...] > Should we > concentrate on ground based work and de-emphasize space based > observation until some smart cookie makes it a lot cheaper and easier > to get up there? I hope I have framed the question usefully. A fair and useful question indeed. Let's consider the four Great Observatories: Hubble Space Telescope, Gamma Ray Observatory, Advanced X-ray Astrophysics Facility, and Space Infrared Telescope Facility. (The first two are approved projects, AXAF is conditionally approved, and SIRTF is on schedule for "new start" approval in FY 1992 or 1993. My comments about SIRTF apply equally well to the Infrared Space Observatory, an approved ESA project.) The main justifications for HST were improved spatial resolution, increased wavelength coverage, and darker sky background (compared to ground-based telescopes). It is possible, as you suggest, that adaptive optics might provide the improved resolution. Indeed, interferometric techniques should give much higher resolution than HST. However, all these techniques are limited either to bright objects or (for adaptive optics) to a small field of view near a bright object. The increased wavelength coverage (primarily in the ultraviolet, but also in the infrared for the second-generation instruments) and the darker sky cannot be attained from the ground. For the other three Great Observatories, essentially none of their work can be done from the ground. The atmosphere simply does not transmit X-rays or gamma rays. In the case of SIRTF, while a small portion of the infrared spectrum does reach the ground, the atmosphere is so bright at these wavelengths that ground-based telescopes will always be a factor of 1000 times less sensitive and thus are wholly unable to study many types of objects. (Improved detectors will not overcome the sensitivity limit, since the noise source is the sky photons and not the detector.) These limits do not seem to be technical; at least, no advance in technology that I can conceive of will remove them. (Unless you want to talk about removing the atmosphere altogether :-) ) If we want to do the types of observations the Great Observatories will, we will have to go above the atmosphere. Platforms other than satellites, i.e. balloons, sounding rockets, and aircraft, can perhaps be used, but these are not really cheaper on a per-observing-minute basis. There is still a question, as always in setting priorities for science funding, whether the particular observations to be made are worth the mission cost. Certainly the process must consider what else could be done with the money. Another consideration must be whether improved technology, either in instrumentation or in launch costs, could make the mission cheaper or better. Obviously setting priorities is not an objective process, and reasonable people will disagree. However, it certainly seems fair to say that many of the observations made from space cannot be replaced by ground-based observations. -- Steve Willner Phone 617-495-7123 Bitnet: willner@cfa 60 Garden St. FTS: 830-7123 UUCP: willner@cfa Cambridge, MA 02138 USA Internet: willner@cfa.harvard.edu ------------------------------ Date: 1 May 89 05:29:09 GMT From: cs.utexas.edu!oakhill!dover!fullmer@tut.cis.ohio-state.edu (Glen Fullmer) Subject: Re: wireless electricity In article <2841@pegasus.ATT.COM> psrc@pegasus.ATT.COM (Paul S. R. Chisholm) writes: >In article <269@poppy.warwick.ac.uk>, phupp@warwick.ac.uk (S Millington) writes: >> There have been recent sugestions that a satellite in a >> geostationary orbit could use a high power microwave transmitter to >> transmit power to earth, this would mean that the solar cells picked >> up more light than they would on earth. > >Recent? These proposals were first made in the seventies. The Didn't Nikola Tesla transmitted wireless power sufficient to light a light bulb over a considerable distance sometime near the turn of the century? Old? Who's old? Some of us have better memories than others!-- _____ _ "For a successful technology, reality must take precedence" {____/ // "over public relations, for Nature cannot be fooled." \ // _ __Richard P. Feynman, Appendix F of Shuttle Disaster Report {____/ atmosphere (over Colorado, I believe.) I forget how big it was, but it > stayed in the atmosphere for a few minutes, and it didn't burn up. It > just kept going back out into solar orbit. There is a color picture in a back issue of National Geographic. IT was a feature article on meteors and such. Within the last 5 years I believe. The hunk of rock was big enough to have taken out a good size town. Up in the 10KT (?) range of energy, had it struck. When you start thinking about Tunguska, the early 70's pass above, the .5M mile misses of really big stuff in the last 25 years ... it makes you feel like you're sitting on the bulls eye of some cosmic dart game. ------------------------------ Date: 1 May 89 16:36:43 GMT From: hpda!hpcuhb!hpscdc!chris@ucbvax.Berkeley.EDU (Chris Schiller) Subject: Re: Earth based - will it always win? I took a spacecraft design course at the University of Colorado which was taught by engineers from Martin Marietta in Denver. Most of them worked on the Magellan project. I remember them mentioning that an investigation was performed to determine whether an Earth-based or probe-based radar would give better resolution of Venus. If I am remembering correctly, the studies showed that a spacecraft could do it better, but not by much. The investigation was done in the early eighties, and the ground based technology may have come a long way since then. Of course if Magellan would have been launched when scheduled, September '86, the primary mission would have been completed long ago. I also think I remember some complaints about the decision to not allow Centaur on the shuttle. The less energetic IUS really restricts the available transfer orbits, and gives rise to some of the present hurried and frantic shuttle launch activities. Chris Schiller uucp: hplabs!hpscdc!hpsctcd!chris smtp: chris@hpsctcd arpanet: chris%hpsctcd@hplabs.hp.com Many hands make light work: Somewhere between the wave and particle theories. ------------------------------ Date: 1 May 89 15:45:07 GMT From: att!oucsace!mstuard@ucbvax.Berkeley.EDU (Mike Stuard) Subject: Re: Smart Pebbles In article <1829@blake.acs.washington.edu>, sealion@blake.acs.washington.edu (sealion) writes: > In article <1989Apr28.151108.15074@cs.rochester.edu>, yamauchi@cs.rochester.edu (Brian Yamauchi) writes: > > In article <3761@aplcomm.jhuapl.edu> jwm@aplvax.jhuapl.edu (Jim Meritt) writes: > > >That looked _NEAT_!!!!! That thing sitting there bursting its jets holding > > >a hover was slick!!! > > The film shows the first full-bore laboratory test of what is sometimes > referred to as a "smart bullet". The space based weapon is designed to > eliminate it's target (ICBMs) through high speed collision during the > boost and mid-course phases of flight. If this is to be a space based weapon why would there be ground based test of this nature. I would think that the manuverability and acceleration requirements would be different in orbit than in a 1g atmospheric situation. We know that it can accelerate at at least 1g and is quite manuverable (based on the apparent stability during the hoverv) but what real data about its capabilities in orbit can be determined in this test. Though it was really neat to watch. -- Deviant disclaimer: OOP! ACK! DON'T PANIC, It's not that important anyhow. /-> mstuard @ ace.cs.OHIOU.EDU Michael J. Stuard--> cs614 @ ouaccvmb.BITNET \-> 73100,3646 @ Compuserve(checked every blue moon or two) ------------------------------ Date: Mon, 1 May 89 15:48:28 PST From: Peter Scott Subject: Magellan update update X-Vms-Mail-To: EXOS%"space@andrew.cmu.edu" A new status report was just posted for Magellan at 3pm, PDT, Monday May 1st: Officials at Kennedy Space Center in Florida have announced a new launch date of Thursday, May 4th for the shuttle at 10:48 PDT. The weather is expected to be good at Kennedy on Thursday, but will begin to degrade on Friday and be poor over the weekend. The next status report is scheduled for May 2nd at 1pm PDT. Peter Scott (pjs@grouch.jpl.nasa.gov) ------------------------------ Date: 1 May 89 19:23:15 GMT From: tektronix!tekgen!tekred!larryb@uunet.uu.net (Larry Brader) Subject: Re: Smart Pebbles In article <3761@aplcomm.jhuapl.edu> jwm@aplvax.jhuapl.edu (Jim Meritt) writes: > >See the film footage of the test of the smart pebble? > Yes... It was impressive. I only counted 5 thrusters on the cyclinder. They mention on TV is was 6feet long and weighed about 150lbs (fully fueled?). The test route that object followed was rise 8feet (?) move horizontally along long axis about 10-15 feet, hover and shutoff. The center engine provided the main lift, and the 4 on the one end controlled movement. I must have missed something because with just the 4 controllers on the cyclinder it must be hard to move horizontally without spining around the center. They have very sensitive accelometers in order to adjust the 4 engines to maintain control. The engines look very similiar to Williams International ceramic engines that they have been developing. I saw them in some trade magzines a few years ago. They didn't mention anything about thrust ratio's, burn rate, or engine life span. I believe that they burn a solid fuel. I wonder if they would be useful on a Getaway special, or probe. I wonder if the military will ever allow them for use in the civilian world. Only when they have an antimatter engine ;-( -- Larry Brader :: larryb%speed.cna.tek.com@relay.cs.net Of course these are my views, any resemblance to reality is merely a concidance. "He's dead Jim, You grap his tricorder and I'll get his wallet" ------------------------------ Date: 1 May 89 13:20:00 GMT From: genrad!dls@husc6.harvard.edu (Diana L. Syriac) Subject: Final Frontier June 1989....EXCELLENT ISSUE The June issue of Final Frontier is one of the best I've seen in a long time. I'd recommend it as excellent reading for anyone who's interested in Space Tourism. Among other things, it has an article describing the "Ultimate Vacation", plus lists all of the various "Space-on-Earth" camps available in the US, plus lists all the organizations (including address)which have taken an active interest in promoting future space tourism. There's an article on Artificial Gravity being studied here in Massachusetts; there's a large article on the International Space University, started at MIT (but worldwide) a couple of years ago; another article on Spaceplanes. And on top of all that, they still have room to describe the STS-29 shuttle mission file and the new STS-30 Magellan project. Plus, there's a "phone in your vote" poll on Citizen's in Space. Phone is 1-900-786-3663 ($1.25 per phone call, touch tone phones only), and question is: "Should NASA resume its program to take ordinary citizens on the shuttle?" This is definitely a collector's items when it comes to space magazines. Back issues (and subscriptions) can be ordered thru: Final Frontier PO Box 20089 Minneapolis, MN 55420 Subscription is $14.95 for one year (6 issues), back issues are "$5.00 for each issue plus $2.50 postage and handling". You can also use a credit card by phoning 612-884-6420. I have no affiliation whatsoever with Final Frontier, I'm just an interested reader. -> Diana L. Syriac <- ->USmail: GenRad Inc., Mail Stop 6, 300 Baker Ave, Concord, Mass. 01742 <- ->usenet: {decvax,linus,mit-eddie,masscomp}!dls@genrad.com <- ->tel: (508) 369-4400 x2459 I'D RATHER BE FLYING!!! <- ------------------------------ End of SPACE Digest V9 #406 *******************