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 ; Thu, 13 Apr 89 03:17:24 -0400 (EDT) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 13 Apr 89 03:17:15 -0400 (EDT) Subject: SPACE Digest V9 #362 SPACE Digest Volume 9 : Issue 362 Today's Topics: space news from Feb 20 AW&ST Re: Success with cold fusion reported, (Really Power Grids) Re: DSN mission launch dates Re: space news from Feb 13 AW&ST Re: Questions and Henry Re: Building a fusion-based rocket Re: Power vs Energy ---------------------------------------------------------------------- Date: 12 Apr 89 03:01:51 GMT From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: space news from Feb 20 AW&ST [A correction: despite the comments in AW&ST, folks from both Fermilab and CERN have pointed out that Fermilab currently holds the record as the world's biggest antimatter source. Not that that's such a massive distinction, mind you: if all the antiprotons produced to date were combined with positrons to make antihydrogen, there would be roughly enough to fill an anti-ping-pong ball at one atmosphere. (My thanks to a friend at CERN for this information.)] India asks France for technological assistance in launch-vehicle development, specifically nozzle design, cryogenic propulsion, and clustering of liquid engines. [Fat chance.] First Delta 2 launch successful Feb 14. NASA is upset about a coming personnel crisis: 70% of its senior managers are eligible for retirement within two years, and many of them are expected to leave. Fletcher says the situation is "desperate". (AW&ST's editorial this week inquires why this problem took Fletcher et al by surprise, given that it's been obvious since the hiring freezes in the 1970s that there would be few middle-aged managers to replace the old ones.) NASA is considering ideas ranging up to turning several of the NASA centers into contractor-run facilities. The problem is that NASA cannot afford to pay enough to keep its managers or hire people with equivalent experience. There has also been an unusually high number of resignations among newly-hired managers of late. [To be blunt, if NASA forgets silly ideas like privatizing some of the centers and just tries to muddle through, this could be the best thing that's happened to it in a long time. NASA's supervisor:worker ratio today is much too high, twice what it was during Apollo. Putting some of the relatively young and inexperienced people in positions of responsibility might be just what's needed to get things moving again.] Florida governor asks state legislature to set up a Spaceport Authority to establish commercial launch facilities at the Cape (preferably using some existing mothballed pads) and a sounding-rocket range on property owned by Eglin AFB. The Bush Administration supports the idea in general. Many people doubt that there is enough long-term demand to justify such a project, though. Arianespace signs contracts for the production batch of 50 Ariane 4s. The bulk buy is expected to cut costs by about 20%. Article on preparations for the first Titan 4 launch, which will carry an upgraded-version Defense Support Program early-warning satellite. The infrared telescope is expected to return useful intelligence data as well; the latest upgraded version is known to be capable of tracking aircraft if they are using afterburners. Among other minor improvements, this DSP version has computer and software improvements to manage its own systems and station-keeping if cut off from ground command. The next one, to go up on the shuttle next year, will add a laser communications system which will link it to other DSP satellites, allowing "sideways" data relay to circumvent jamming. There is a faction which wants to continue upgrading the DSP series rather than replacing it with the SDI-developed BSTS system. An interesting set of photos comparing successive generations of DSP birds, with successively more elaborate sensors and bigger solar arrays. Navy begins construction of four Lightsats for launch this fall, pulling ahead of the USAF (which fought the concept for a while). The first three, carrying various experimental packages, will go up together on a Scout (probably). The fourth, carrying an experimental system to locate sources of radio interference, is almost finished but does not have a definite launcher yet: Scout and Pegasus are possibilities. [Smells like they want to use Pegasus but don't want to say so until it flies successfully.] These are basically R&D missions, although they may have some operational utility if they work well. The official position right now is that these are "niche" spacecraft that cannot replace the big expensive ones. [That may change if they work well.] NRC report says SDI beam-weapon work implicitly assumes availability of advanced space power sources, on which little work is being done. One significant issue, for example, is whether exhaust and vibration from chemical systems make them unacceptable; only analytical studies have been done on this, with inconclusive results, and the space experiments that would settle the question are several years off and have low priority. USAF building special single-point suspension facility to study the control dynamics of large lightweight space structures. Pratt&Whitney offers various upgrades for the RL10 engine to Centaur customers; business is booming. Some of the upgrades are derived from work done on the late, lamented Shuttle-Centaur program. Study commissioned by Comsat Corp. shows satellites holding their own against fiber-optic cables for the near future. -- Welcome to Mars! Your | Henry Spencer at U of Toronto Zoology passport and visa, comrade? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: Mon, 10 Apr 89 8:17:08 CST From: Will Martin -- AMXAL-RI To: sgi!shinobu!shinobu.sgi.com!watson@UCBVAX.BERKELEY.EDU Cc: space@ANDREW.CMU.EDU Subject: Re: Success with cold fusion reported, (Really Power Grids) >This implies something that deserves explicit mention: there is nothing >I know of that makes a "grid" incompatible with decentralizing energy >production. In at least some places, individuals with windmills sell >their surplus power back to a utility. If each household made enough >power on the average, couldn't we still use the "grid" just to balance the >load? What if utilities stopped producing and became brokers? I had just recently read an article on home power generation in a back issue of "Blair & Ketchum's Country Journal" magazine -- July 1985, p. 54. The article is on hydro power, but the issues regarding tying into the power grid are applicable to any source. "A generator must turn at a constant speed to produce electricity at a constant voltage. There are two basic ways to keep that speed constant. One is to make sure that the generator is always running under the same load -- a full load. Since a home's electric needs change as heating units and appliances go on and off, a switching mechanism can be built into the power plant. The house gets whatever it needs, and the remainder can be sold to the power company." "There are some complications with this... One is that the equipment to connect with the utility system isn't cheap. [A 50 kW unit's tie-in circuitry] cost about $8000, although power sales will eventually recover that cost. Another difficulty, an ironic one for someone with a generator in the yard, is that when the commercial power is off you can't be running your generator and so you won't have power either... That's because such connected generators ... need commercial power to keep them in step with the rest of the system, unless they have costly additional control mechanisms. Besides that, if the power is off somewhere else in the utility grid, the power company can't let you keep gnenerating, even if you had those controls. ... They have crews out fixing the lines. The power is supposed to be off in those lines. But if you're generating, and you're connected, then there's power going into those lines that are supposed to be dead. The lineman could get the last surprise of his life..." [The other one of the "basic ways" mentioned above is what the subject of the article does -- he has a quick-acting governor that controls the flow of water into his turbine and thus varies the electricity produced directly with the demand.] Anyway, there can be cost and operational disadvantages from having individual home generator units tied into the power grid. I must admit that I like the idea of total independence from commercial power, but I tend to think that it is still probably more feasible to stay with central generators and existing distribution grids in built-up areas. Where the home-fusion plant sounds good, though, is in isolated areas. It, along with satellite communications, can give rise to more and more isolated individual smallholdings, independent fiefdoms scattered about in areas now too inhospitable to support them currently. Now, there are only a few such, all based on farming, like some of the polygamists' compounds you hear about at times on "tabloid TV". With independent power and satellite commo, though, somebody with other skills, like programming or writing or what-have-you, could live in such a fashion too. Myself, I always had an idea that it would be interesting to live isolated in the middle of a mesa big enough to have radial Beveredge antennae (these are very good but very long short- and medium-wave wire antennae) going off in about 8 directions... (Probably spelled wrong -- my references aren't here.) Can't usually get much water in such a situation, though, and, while solar power might produce enough to live on, a fusion plant would give enough for air-conditioning and maybe some way to get water... Regards, Will Martin ------------------------------ Date: 10 Apr 89 17:50:00 GMT From: m.cs.uiuc.edu!kenny@uxc.cso.uiuc.edu Subject: Re: DSN mission launch dates /* Written 2:40 pm Apr 6, 1989 by PJS@GROUCH.JPL.NASA.GOV in m.cs.uiuc.edu:sci.space */ /* ---------- "DSN mission launch dates" ---------- */ I just got a list of launch dates for missions supported by the DSN through 1990. I don't have a glossary, so if you don't know what one of these acronyms means, don't ask me. /* End of text from m.cs.uiuc.edu:sci.space */ BS-3a ? COBE Cosmic Background Explorer Determine the spectral anisotropy of the cosmic microwave background DFS ? Deutsches something-or-other, I think... EUTELSAT EUropean TELecommunications SATellite FLTSATCOM FLeeT SATellite COMmunications U.S. Navy communciations satellite GALILEO Mission to explore Jupiter and its moons GMS ? GOES Geostationary-Orbit Earth-observation Satellite Meteorological mission in Clarke orbit GRO Gamma Ray Observatory HST Hubble Space Telescope MAGELLAN Mission to map the surface of Venus MUSES-A ? ROSAT ROentgen SATellite NASA/West German co-operative mission for X-ray astronomy TDF ? TDRS Tracking and Data Relay Satellite ULYSSES (Formerly ISPM--International Solar Polar Mission) Investigate the properties of the heliosphere (The Sun and its environment). Kevin Kenny UUCP: {uunet,pur-ee,convex}!uiucdcs!kenny Illini Space Development Society ARPA Internet or CSNet: kenny@CS.UIUC.EDU P.O. Box 2255, Station A Champaign, Illinois, 61825 Voice: (217) 333-5821 ------------------------------ Date: 11 Apr 89 02:13:01 GMT From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: space news from Feb 13 AW&ST In article <7686@thorin.cs.unc.edu> leech@zeta.UUCP (Jonathan Leech) writes: >>... They really should have launched three of them.] > > Perhaps the effort would better be spent putting more reliable >hardware on board the spacecraft, and better trained personnel on the >ground. Of what use would *three* failed Mars probes be? :-) Of what use would one successful one be? Note that they didn't lose P2 to P1's problem. They probably wouldn't have lost the hypothetical P3 to P2's problem -- and P2 was pretty close to the key part of the mission. One more might have been enough to push the next mistake past the Phobos encounter. The way you find out about these things is to try them. The major factor in how quickly you learn is how often you try. -- Welcome to Mars! Your | Henry Spencer at U of Toronto Zoology passport and visa, comrade? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 11 Apr 89 02:32:17 GMT From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Questions and Henry In article <713@rocksanne.UUCP> kirby@bozo.UUCP (Mike Kirby (co-op)) writes: >1) Henry, do you have anything positive to say about the U.S. space program? > I mean do we do anything right anymore? Oh, once in a while. Why, you did something right as recently as 1965. :-) More seriously, I am quite excited about both Magellan and Galileo. They are basically the last big things out of the Apollo-era pipeline, with very little left in the pipe behind them... but they're nifty all the same. Much more significantly, the US is possibly the only country that can really open the skies to mankind. And despite recent setbacks, it still has a fair chance of doing it. The key is to look at private industry, not government; the US government will never accomplish it, but the US is nearly unique in being a place where private industry can have a try at it without having to sell their souls to the government first. >2) What is the pegasus? Pegasus is one of the brightest spots in the picture right now: a small air-launched space launcher, being built as a joint project by Orbital Sciences and Hercules. Although I'm rooting for them all the way, their biggest accomplishment will be secure if they launch once and then go broke: they've built Pegasus in about two years for about $60M [I may have that number slightly wrong, but that's the right area]. Even if they go under after their first launch, they'll have proved that you don't have to do things the NASA way, spending billions and taking decades. Private investors can't afford to sink billions of dollars in space projects and wait decades for possible return... and NASA, from its entrenched position as The Experts on the matter, naturally assures them that there is no other way. Two years and $60M is a very different story. If OSC/Hercules get one bird into orbit, others will follow. -- Welcome to Mars! Your | Henry Spencer at U of Toronto Zoology passport and visa, comrade? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 10 Apr 89 21:04:46 GMT From: psivax!quad1!ttidca!sorgatz@uunet.uu.net ( Avatar) Subject: Re: Building a fusion-based rocket In article <943@psueea.UUCP> sandym@psu-cs.cs.pdx.edu (Sandy Michael) writes: > >What technology do you see the Earth having by the year 3000? >Michael Sandy Given the actual mission progress since 1945, the current technology, the extreme attitudes of American management, the inertia-bound political process that technology must beg it's funds under...plus a few fudge factors...I'd guess that by the year 3000, if there is no total planetary war to wipe out the Race..figure maybe we'll have come back up to having SATURN 5's and be looking at building a real Lunar Colony! No :-)'s here! The space effort is being ruined by the big-EGO managers of NASA, and their "Good-Ole-Boys-Network". Most of these clowns have swell, college degrees in Mech. Eng. or whatever, but they've never turned a wrench, cut a part, or designed their way out of an airline barf-bag!! They've all gone to management "Charm School", and "know" how to motivate! Big !@#$%^ deal! I openly challenge anyone with the balls to respond, to explain the huge gap between NASA management salaries and those of the NASA Engineering staffers. They can also explain the nepotism, the wasted paper-chase-studies, the whole series of bad decisions that lead to the Challenger mess..and then, if it's not too much trouble, they can explain how, (in light of all this) useful this 'profession' named management is. Scientists and Engineers do not need 5 layers of useless dross between themselves and the Congress, it only makes the work more expensive and slower, when is this going to change? By the year 3000? I hope so... -- -Avatar-> (aka: Erik K. Sorgatz) KB6LUY +-------------------------+ Citicorp(+)TTI *----------> panic trap; type = N+1 * 3100 Ocean Park Blvd. (213) 450-9111, ext. 2973 +-------------------------+ Santa Monica, CA 90405 {csun,philabs,randvax,trwrb}!ttidca!ttidcb!sorgatz ** ------------------------------ Date: 11 Apr 89 02:09:20 GMT From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Power vs Energy In article <3603@aplcomm.jhuapl.edu> jwm@aplvax.jhuapl.edu (Jim Meritt) writes: >Concur that power is an issue in general in space flight, but it should >not be near the issue that ENERGY is. It depends on what kind of propulsion we are talking about. With current systems, yes, energy is the big problem. Rocket engines actually handle rather a lot of power -- an SSME is 5-7 gigawatts, as I recall -- but they cope by keeping it at arm's length, pushing waste heat back into the fuel as fast as it (the heat) leaks out. Trouble is, when you hike the exhaust velocity (and hence the thrust per kilo of fuel) a few orders of magnitude, this approach stops working so well. Will cold fusion get us to that point? Good question -- wait and see. Hot fusion probably would; if you look at artists' conceptions of things like inertial-confinement fusion rockets, you'll see big radiator fins up forward. -- Welcome to Mars! Your | Henry Spencer at U of Toronto Zoology passport and visa, comrade? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ End of SPACE Digest V9 #362 *******************