Date: Wed, 2 Jun 93 05:24:09 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #659 To: Space Digest Readers Precedence: bulk Space Digest Wed, 2 Jun 93 Volume 16 : Issue 659 Today's Topics: Big Rock Can Hit Earth in Yr 2000 Hey Sherz! (For real!) Cost of LEO (2 msgs) lunar metallurgy Space Science information on the Web Why a far side Science station. 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: Wed, 2 Jun 1993 07:38:50 GMT From: Dave Tholen Subject: Big Rock Can Hit Earth in Yr 2000 Newsgroups: sci.space,talk.environment,sci.physics,sci.astro Henry Choy writes: > What's going to be done about Toutatis? Nothing, other than some astronomical observations. > It's reputed to be one km wide and a close visitor of earth. It's larger than that. > It doesn't have an invitation, It doesn't need an invitation. > but in the year 2000 it may come as close > as the moon's orbital radius, maybe even closer. No it won't. Even during the closer approach of 2004, it will only pass at about four times the distance of the Moon. That's as close as it will get for some time to come. The approach in 2000 is not as close as the one we just had last year. > Is anyone thinking of > - blowing it away? > - carving it into little pieces? > - changing its flight plan? Some would like to test such options, in case an asteroid is found to be on a collision course at some time in the future. > - stopping it at customs? Customs can't stop it. > - revoking its visa? It doesn't have one, nor does it need one. > - hitching on for a joyride? That's been suggested too (seriously). Imagine the bungee cord one would need! > - moving earth (and heaven too if it comes to that)? You must be a disciple of Abian. > - what to think about after reading this? Just the kind of comic relief I needed after a hard day at the office. ------------------------------ Date: 2 Jun 1993 01:24:18 -0700 From: Ken Hayashida Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space aws@iti.org (Allen W. Sherzer) writes: >>>>Don't include contingency satellitte return missions. It would have >>>>been cheaper to build new ones and pop them off. Wingo responded: >>If you want to make statements like this back them up with numbers both the >>cost of reconstruction Sherzer says: >Already done Dennis. A very conservative estimate would be that a typical >replacement to a typical satellite could be built and luanched for about >$225 M which is less than half the cost of a rescue mission. >Perhaps YOU would like to show us a case where it was cost effective? >In spite of your complaints, we haven't seen one. I say: This is another example folks of an unreferenced number which mr. Sherzer puts out. Mr. Sherzer, could you please inform the readers where and how you make these estimates. Until you do, the post is meaningless because the numbers can not be confirmed nor understood. I urge you to follow standard science paper procedures in order to support your contentions, that means posting references, page numbers, and methods. >Intelsat is the only place I know of where this applies. Yet it was >only performed after receiving huge taxpayer paid subsidies to do it. >They didn't think it was worth paying the total cost themselves. > Allen Allen, do understand what it takes to get three astronauts out on a simulataneous EVA? You must! How can you call that unworthy? If you claim to support spaceflight by men and women, how do you propose to support space operations and space station work if you can't learn how to perform EVA's? ken ------------------------------ Date: 2 Jun 1993 01:41:18 -0700 From: Ken Hayashida Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space Wingo says: >>Marginal Cost of Shuttle Mission >>$37 million (From Space News a few months ago) sherzer writes: >Marginal cost of what? Divide the Shuttle hardware line item in the budget >by the flight rate and you will see that they consume $100 to $200 million >per flight. Just for my own edification, it is not clear to me which line items you are looking at. please post how you are calculating your figures so the world can understand you figures. >>Also I just had to get this in. Are you going to charge DCX for the thermal >>protection system developments for the Shuttle that is being applied to >>the DC series? >I wold use the normal accounting methods. I am willing to hold DC to those >numbers and I point out that is far stricter than I do for Shuttle. Please post your view of what normal accounting methods are. I cannot ascertain your statement and my analysis of Saturn launch vehicle costs without you posting your view of "normal accounting methods." Wingo said: >>Lighten up Allen. Shuttle ain't perfect but it is a necessary step in the >>process. Allen said: >So why should Shuttle get special treatment? As to it being a necessary >step, maybe or maybe not. But if we are going to make progress, we must >not waste billions just to serve our emotional attachment. We are not wasting billions for emotional attachment... we have a program which is helping Americans maintain preemince in spaceflight. I don't ask for special treatment for the shuttle program. I, however, object to your overly critical stance of the program. Your posts are decidedly slanted against the program. Every post you make has at least one attempt to discredit the program. As for my postings, I'm wasting so much time trying to address your flames, that I haven't been able to finish my paper on Saturn V launch history, STS launch history. I reiterate: please post your accounting methods, your references for DC-1 costs, your references for the shuttle program costs, we need to be able to confirm these numbers on our own. Thanks for your attention. Sorry I didn't get a chance to meet you at ISDC. I would have enjoyed discussing these matters in person.8-) ------------------------------ Date: Wed, 2 Jun 1993 08:06:15 GMT From: Nick Janow Subject: lunar metallurgy Newsgroups: sci.space rcs@cs.arizona.edu (Richard Schroeppel) writes: > There's a minor glitch here [alloys too reactive to be useful on Earth] - > any lunar environment with people nearby will have minor outgassing of > water vapor, air, & CO2. Although this isn't comparable to an Earth > rain-storm in corrosive power, it will be a nuisance for things made of > potassium, for example. Another side of this coin is that you will be > reluctant to make things that can't be brought inside the airlock to be > worked on, machined, assembled, etc. Not so. The outgassing should be very minor. A bit of discolouration over a few decades shouldn't be a problem, if there's even that much effect. Also, there should be a lot of things that won't need to be taken inside to be worked on. I'm thinking of dragline structures, but it may apply to smaller things too. Bringing in an item causes more than oxidation risk; it causes thermal stress and contamination (dust, grease, etc), and requires time/effort for dealing with the in/out transaction. Also, two of the technologies that needs to be developed to make a space colony feasible are teleoperation and material working in a vacuum. Once these are developed, there won't be much reason for taking something inside to be worked on. -- Nick_Janow@mindlink.bc.ca ------------------------------ Date: Wed, 2 Jun 1993 10:40:59 GMT From: Frederick Roeber Subject: Space Science information on the Web Newsgroups: sci.space A first version of the new Space Science overview page is now available on the world-wide-web. The WWW is a global hypermedia network sitting on top of the internet, and incorporating most of the popular protocols, including ftp, wais, gopher, archie, nntp, etc. (See comp.infosystems.www for more info.) This page is available at http://info.cern.ch/Space/Overview.html . There is also a pointer to it under the popular "information by subject" page, under "Space Science." As yet, it's just a simple list of available information; if it grows much larger I may reorganize it with explanatory text. So far, the list includes: Answers to Frequently Asked Questions on sci.space NASA Ames Research Center archives NASA Astrophysical Data System user guide NASA JPL FTP archive NASA Langley techreports (directory) NASA Langley techreports (searchable) NASA Spacelink (interactive session) National Space Science Data Center Online Data and Information Service (interactive session) Space Telescope Science Institute electronic information service Space Telescope European Coordination Facility star catalog database (interactive session) Voyager, Hubble, and other images Yale Bright Star Catalog Orbital Element Sets: NASA, TVRO, Shuttle Orbital Element Sets: NASA, TVRO, Molczan, CelBBS, Shuttle Orbital Element Sets: NASA, Molczan Back issues of the Electronic Journal of the Astronomical Society of the Atlantic NASA Headline News NASA Extragalactic Database National Oceanic and Atmospheric Administration database Vincent Cate's list of companies related to the space industry Skywatch Frequently Seen Acronyms Daily Ionospheric Reports Delta Clipper images Some of the web browsers (e.g, Mosaic, available by anonymous ftp at ftp.ncsa.uiuc.edu in /Mosaic) can handle images, movies, and audio files. For example, clicking on "Delta Clipper images" will produce a list of images; clicking on one of them will display the image. The JPL FTP archive has many interesting images. Please come and browse around. If you know of information available on the net not listed on the page, please let me know. -- Frederick G. M. Roeber | CERN -- European Center for Nuclear Research e-mail: roeber@cern.ch or roeber@caltech.edu | work: +41 22 767 31 80 r-mail: CERN/PPE, 1211 Geneva 23, Switzerland | home: +33 50 20 82 99 -- "Sorry, baby, I can't take you to the pizza joint tonight, I've got to go back to the lab and split the atom." -- Ayn Rand, "What is Romanticism?" ------------------------------ Date: Wed, 2 Jun 1993 06:01:26 GMT From: Frank Crary Subject: Why a far side Science station. Newsgroups: sci.space In article <1u5i3g$49e@access.digex.net> prb@access.digex.net (Pat) writes: >Is the earth uniformly radio noisy? In the United States, there are federal "radio free" zones, such as Table Mountain, Colorado, and frequencies reserved for science. But these laws only reduce the problem slightly. Frank Crary CU Boulder ------------------------------ Newsgroups: sci.space From: Frank Crary Subject: Re: Moon Base Message-Id: <1993Jun2.054619.7664@ucsu.Colorado.EDU> Sender: USENET News System Nntp-Posting-Host: ucsu.colorado.edu Organization: University of Colorado, Boulder References: <24747@mindlink.bc.ca> Date: Wed, 2 Jun 1993 05:46:19 GMT Lines: 13 Source-Info: Sender is really news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU In article <24747@mindlink.bc.ca> Nick_Janow@mindlink.bc.ca (Nick Janow) writes: >No, but they do have application on the moon, and perhaps Mercury and some of >the other moons in the system. Some of the technology and knowledge may be >applicable to Mars as well (such as for processing Martian soil into fuel for >exploration vehicles and a return to Earth). I wouldn't be useless, but Mars also has an atmosphere and many resources can be produced from that (fuels, nitrogen and to a lesser degree, water.) The soil processing most applicable to Mars would be the utilization of ~10 meter deep materials (permafrost). Frank Crary CU Boulder ------------------------------ End of Space Digest Volume 16 : Issue 659 ------------------------------