Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.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 ; Wed, 6 Feb 91 01:42:58 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 6 Feb 91 01:42:52 -0500 (EST) Subject: SPACE Digest V13 #117 SPACE Digest Volume 13 : Issue 117 Today's Topics: Information sources for frequent space questions (1 of n) Re: The edge of the solar system Augustine recommendation for heavylift launcher Re: The edge of the solar system Re: some questions Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 1 Feb 91 12:01:42 GMT From: sdd.hp.com!elroy.jpl.nasa.gov!jarthur!nntp-server.caltech.edu!mustang!data.nas.nasa.gov!amelia!eugene@ucsd.edu (Eugene N. Miya) Subject: Information sources for frequent space questions (1 of n) Many space activies center around large Government or International Bureaucracies. In this country that means NASA. If you have basic information requests: (e.g., general PR info, research grants, data, limited tours, and ESPECIALLY SUMMER EMPLOYMENT (typically resumes should be ready by Jan. 1), etc.), consider contacting the nearest NASA Center to answer your questions. EMail typically will not get you any where, computers are used by investigators, not PR people. The typical volume of mail per Center is a multiple of 10,000 letters a day. Seek the Public Information Office at one of the below, this is their job: NASA Headquarters (NASA HQ) Washington DC 20546 NASA Ames Research Center (ARC) Moffett Field, CA 94035 [Mountain View, CA, near San Francisco Bay, you know Silicon Valley 8-) ] NASA Ames Research Center Dryden Flight Research Facility [DFRF] P. O. Box 273 Edwards, CA 93523 NASA Goddard Space Flight Center (GSFC) Greenbelt, MD 20771 [Outside of Washington DC] NASA Lewis Research Center (LeRC) 21000 Brookpark Rd. Cleveland, OH 44135 NASA Johnson Manned Space Center (JSC) Houston, TX 77058 NASA Kennedy Space Flight Center (KSC) Titusville, FL 32899 NASA Marshall Space Flight Center (MSFC) Huntsville, AL 35812 NASA Langley Research Center (LaRC) Hampton, VA 23665 [Near Newport News, VA] Not a NASA Center, but close enough: Jet Propulsion Laboratory [JPL/CIT] California Institute of Technology 4800 Oak Grove Dr. Pasadena, CA 91109 There are other small facilities, but the above major Centers are set up to handle public information requests. They can send you tons of information. Specific requests for software must go thru COSMIC at the Univ. of Georgia, NASA's contracted software redistribution service. You can reach them at cosmic@uga.bitnet. If this gives you problems, tell me. NOTE: Foreign nationals requesting information must go through their Embassies in Washington DC. These are facilities of the US Government and are regarded with some degree of economic sensitivity. Centers cannot directly return information without high Center approval. Allow at least 1 month for clearance. This includes COSMIC. EUROPEAN SPACE AGENCY (O) 202/488-4158 955 L'Enfant Plaza S.W., Washington, D.C. 20024 Arianespace Headquarters Boulevard de l'Europe B.P. 177 91006 Evry Cedex France ARIANESPACE, INC. (O) 202/728-9075 1747 Pennsylvania Avenue, NW, Suite 875, Washington, DC 20006 SPOT IMAGE CORPORATION (FAX) 703/648-1813 (O) 703/620-2200 1857 Preston White Drive, Reston, VA 22091 National Space Development Agency (NASDA), 4-1 Hamamatsu-Cho, 2 Chome Minato-Ku, Tokyo 105, Japan SOYUZKARTA 45 Vologradsij Pr., Moscow 109125, USSR SPACE COMMERCE CORPORATION (U.S. agent for Soviet launch services) 504 Pluto Drive, Colorado Springs, CO 80906 (O) 719/578-5490 69th flr, Texas Commerce Tower, Houston, TX 77002 (O) 713/227-9000 Additionally information is frequent asked about: Space camp: Alabama Space and Rocket Center 1 Tranquility Base Huntsville, AL 35805 205-837-3400 U.S. SPACE CAMP 6225 Vectorspace Blvd Titusville FL 32780 (407)267-3184 (registration and mailing list are handled through Huntsville -- both camps are described in the same brochure) There is talk of a space camp to be located next to NASA Ames. Watch that space. "It's not a message. I think it's a warning." -- Ripley ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 31 Jan 91 18:55:36 GMT From: van-bc!rsoft!mindlink!a684@ucbvax.Berkeley.EDU (Nick Janow) Organization: MIND LINK! - British Columbia, Canada Subject: Re: The edge of the solar system Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu That's a misleading subject line. It gives the impression that there is a clearly defined "edge" to the solar system, while in fact any boundaries are probably very vague. What defines the "edge"? Some level of gravity? Some density of mass? Some definitions may have our "edge" overlapping that of several nearby stars. Who decides what the definition is? :) ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: Fri, 1 Feb 91 21:18:25 EST From: John Roberts Organization: National Institute of Standards and Technology formerly National Bureau of Standards Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. To: space@andrew.cmu.edu Subject: Augustine recommendation for heavylift launcher >Date: Mon, 21 Jan 91 09:42:30 -0500 >From: "Allen W. Sherzer" >Subject: One Small Step for a Space Activist... (vol 2 no 1) > One Small Step for a Space Activist... > by > Allen Sherzer & Tim Kyger >... >1. New heavy Lift Vehicle (HLV). The Augustine committee advocated reduced >reliance on the Shuttle and the construction of a new HLV. This could reduce >costs and free up money for other projects. The current favorite (gets the >most hype and has strong Senate support) is Shuttle-C or some variant. Shuttle >C would work but may not be the best choice: other alternatives (Heavy Lift >Delta and Titan V) may cost less than half as much to develop and operate. >Activists will need to monitor this to insure that the design meets space >development goals and not Congressional political goals. Whatever design is >selected, we also need to insure that the resulting launcher is man rated >(which is supported by the committee). >Allen Sherzer: (313) 769-4108 (work) (313) 973-0941 (home) aws@iti.org (net) >Tim Kyger: (202) 225-2415 (work) (703) 548-1664 (home) I saw the Augustine Committee's testimony before the US House of Representatives on C-SPAN: The Committee laid forth a set of requirements for an expendable launcher suitable for use in major undertakings such as space station assembly, Moon/Mars missions, launch of large satellites, etc. Part of its function would be to take over much or possibly eventually all of the functions of the current Shuttle. Among the desirable features are lowered cost per pound, higher reliability, greater ability to launch on schedule, adaptability to several forms with different abilities, and ability to be man-rated. It seemed to be understood that the government would help to finance development, and that the developed boosters would be manufactured commercially. Because of the importance of expediting development, these costs would be fairly high, so at least at first there wouldn't be much saving over continued use of the Shuttle, though that could change later. Though the Committee did not specify a particular design, the two approaches that seemed to receive the most attention were some variant of ALS or Shuttle-C. The arguments given were roughly as follows: Shuttle-C - Many components of the current Shuttle (STS) are used to make an unmanned vehicle with payload greater than(?) the manned Shuttle. Because of the heavy use of current technology, development time could be fairly short - possibly only 4 or 5 years. The Shuttle-C concept can be expanded somewhat, but not so far as to specify all the goals listed by the Augustine Committee (i.e. man-rating). There is mention of gradually phasing in new components, once it's operating, but it is not clear that this can be done to any great extent. Advanced Launch System (ALS) - In order to get past the "missile design" mentality that was the basis for current ELVs, ALS uses a large amount of new design, with the goal of producing an inexpensive, reliable heavy launcher. Very wide safety margins and tolerances are used, which reduces performance slightly compared to a high-performance system such as the Shuttle, but the reduced need for exhaustive testing, extreme care, etc. should more than make up for the cost of the additional fuel expended. With this and a rigid methodology governing payload attachment and launch techniques, it is hoped that there will eventually be large reductions in launch costs and in time to prepare and launch. A wide range of configurations should be available, and human-rating is an eventual possibility. Estimated time to full implementation and commercial manufacture is around 8-10 years. In addition to the Augustine Committee testimony, I heard presentations at the NIST-hosted conference on reducing the cost of space infrastructure a year or so back. (That was a good conference - among other things many launch techniques were discussed, including a good presentation on laser launchers by Jordin Kare. :-) For the two launchers in question, the following additional points were brought up: - Shuttle-C is not expected to bring about any per-pound cost savings over continued use of the Shuttle, either in the near-term or the far-term - the whole intent of the program is to get an increased total national payload capacity soon. By contrast, a goal of ALS is to get costs down to about $500 per pound of payload to orbit, or about a tenth of typical current costs. (Many proposed launchers offer varying savings, but this one actually sounds almost plausible, given that such savings would not appear right away due to relatively high design costs.) - There is some advantage in having a variety of designs in use so that the discovery of one flaw does not ground the entire fleet. A problem grounding the Shuttle fleet could also ground the Shuttle-C launchers because of the many components they have in common. - The estimate for launch costs on Shuttle-C not being particularly higher than on the Shuttle is based partly on the presumption that the SSMEs used (and discarded) on each Shuttle-C flight will be old retired engines from Shuttles. (As Henry has said, the SSME is just too expensive to burn up brand new ones on expendable launchers.) The result of this requirement is that for Shuttle-C to remain "competitive", the regular Shuttle must keep flying, and in fact there must be many Shuttle launches for each Shuttle-C launch. - To allow for various ALS payload requirements, boosters (with diameter close to the diameter of the ALS body can be strapped on. Allowed configurations include 4 boosters, or 2, or 1 (!) (A vertical rocket with a booster on just one side looks very strange - presumably the nozzles have to swivel to balance the thrust.) Congress is going to be debating whether to fund Shuttle-C, ALS, both, or neither. Funding both may turn out to be too expensive, so it may be necessary to make a choice. ALS appears to have much greater potential for the future, but will take a while to get ready. Shuttle-C would be ready sooner, but it was designed largely with rapid deployment of SDI hardware in mind, and doesn't offer much beyond an increase in total national payload capacity, and increased maximum single payload. The question then seems to be whether getting a new launcher sooner is worth giving up other possible future benefits. I would offer the speculation that: - SDIO doesn't seem to be planning to launch large quantities of anything anytime soon. - New projects are unlikely to commit to a new launcher until it has actually been built and demonstrated to work. In particular, for a space station timetable, waiting around for development of Shuttle-C or ALS would add another large delay before the start of construction. It will probably be quicker to build a station using existing launchers (Shuttle or expendable) or ones which are already far along in development. For tending the station after assembly, and for possible expansion, whatever new launchers have been developed by that time can be used. Disclaimers: - I haven't said much about the proposed new Delta and Titan launchers because I don't know much about them - Allen can provide a lot more information. I don't see why several types of launcher couldn't be developed and used together - especially if some of them are developed either partially or completely with private funding. There are many possible market niches for different sizes and types of launchers. - My machine may have dropped the automatic Official Disclaimer. Of course it applies to all of my messages, whether it is included or not. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 1 Feb 91 18:20:50 GMT From: sdd.hp.com!samsung!rex!rouge!dlbres10@ucsd.edu (Fraering Philip) Organization: Univ. of Southwestern LA, Lafayette Subject: Re: The edge of the solar system References: <188.27A94707@nss.FIDONET.ORG> Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu In article <188.27A94707@nss.FIDONET.ORG> Paul.Blase@nss.FIDONET.ORG (Paul Blase) writes: JC> This is also noted in John Brandt's article on comets JC> in "The New Solar System" (228) who discusses Jan Oort's JC> conclusion that the "overwhelming majority of comets reside in JC> an essentially spherical cloud around the Sun with a radius of JC> perhaps 20,000 to 100,000 AU. (By comparison, the nearest srs JC> to the solar system, the Alphaha Centauri System, are some JC> 275,000 AU distant.)" According to Wednesday's lecture by Dr. Matese, the dominant characteristic of the Oort cloud is that it is heavily influenced by the galaxy's tidal pull and the passing of nearby stars. Comets in the Oort cloud are definately _not_ stable over the lifetime of the solar system. It is thought that most comets reside in a belt closer to Neptune called the Kuiper belt. I don't think Dr. van Oort made the assertion that most comets resided in the Oort cloud. It is just the major source of short-period comets, due to the fact that they are easily disturbed from their orbits and sent down into the inner solar system (or into the outer solar system, where they come under the gravitational influence of Jupiter or Saturn, which modifies their trajectory even more...) Phil Fraering dlbres10@pc.usl.edu ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 30 Jan 91 19:06:20 GMT From: sdd.hp.com!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss!Paul.Blase@ucsd.edu (Paul Blase) Organization: The NSS BBS, Pittsburgh PA (412) 366-5208 Subject: Re: some questions Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu >> 3) Which are the Pioneers/Voyagers that have left the Solar >> Syatem? CC> The ones that passed the "Last Chance Saloon", just beyond CC> Pluto! CC> Seriously, how do you define "the Solar System". There is a CC> plausible basis for saying that when you cross the heliopause, CC> you have "left the Solar System", but I don't believe any have CC> done so yet. -- the edge of the solar system is more-or less defined as the outermost planet (currently Neptune, I believe). One of the things that the Voyager probes are looking for now is the heliopause. --- via Silver Xpress V2.26 [NR] -- Paul Blase - via FidoNet node 1:129/104 UUCP: ...!pitt!nss!Paul.Blase INTERNET: Paul.Blase@nss.FIDONET.ORG ------------------------------ End of SPACE Digest V13 #117 *******************