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Space Digest Sat, 17 Jul 93 Volume 16 : Issue 886 Today's Topics: DC-X Followon Alert, Mark 2 DC-X Question GPS - who, how,..... GPS in space (was Re: DC-1 & BDB) HRMS: 25 Arecibo Target Stars Hubble, Why the hurry? Lifting body spacecraft (HL-20?) Moon Cable/Beanstalk. SOIL PRODUCTION ON MARS Why are meteor showers seasonal? Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space <your name>" 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: 16 Jul 1993 20:26:03 -0500 From: hvanderbilt@BIX.com Subject: DC-X Followon Alert, Mark 2 Newsgroups: sci.space Space Access Society Action Alert 7/16/93 -- DC-X Followon Funding (Mark 2 Version, 9 pm EDT, this replaces initial afternoon release) Woops. Remember when we told you two days ago that it was time to relax for a while? (In "SAS DC-X News" for 7/14/93.) We hope y'all enjoyed your two-day vacation; things have changed in DC, and key decisions on next years Defense funding, and thus on DC-X's followon, look like being made in this coming week. Background The current DC-X program is funded through flight test and data analysis this fall, and ends after that. There is an ongoing effort to get the US Congress to fund a three-year followon program, variously known as DC-X2 and SX-2 (Space Experimental 2). This could end up as a suborbital vehicle powered by 8 RL-10-A5 engines, capable of reaching Mach 6 (about 1/4 orbital velocity) and 100 miles altitude, built with orbital-weight tanks and structure, and able to test orbital grade heat-shielding. The SX-2 program goal will be to demonstrate all remaining technology needed to build a reusable single-stage-to-orbit vehicle. Once SX-2 has been tested, all that should be necessary to produce a functioning reusable SSTO is to scale up the SX-2 structures and install new larger rocket engines. Proposed FY '94 funding for SX-2 startup is $75 million. The money would come out of the $3.8 billion BMDO budget already pretty much agreed on for the coming year. Total SX-2 program cost over the next three years would be very much dependent on the contractor chosen and the details of the design, but would be on the order of several hundred million. This is the same order of magnitude as typical recent X-aircraft programs such as the X-29 and X-31. SX-2 would start out under BMDO (formerly SDIO), so support from members of the House and Senate Armed Services Committees (HASC and SASC) is vital. The actual name they know SX-2 by is "followon funding for BMDO's SSRT (Single Stage Rocket Technology) program." The specific action we're calling for is for Congress to "fence off" $75 million in BMDO funding for this project next year -- we are not asking for any new funding authority, but rather for reallocation of existing funding toward a DC-X followon. DC-X Test Program Update The DC-X test vehicle was taken out of storage and trucked on its side out to the flight test site at White Sands Missile Range, then erected on the launch pad today. Flight testing should start sometime in the next two weeks. See our next "DC-X News" for details. SSRT Followon Funding Alert What's happened is that Sam Nunn, William Natcher, and John Murtha are tired of having the DOD funding process held up while the President comes up with a coherent gays-in-the-military policy. Nunn is Chair of the Senate Armed Services Committee (SASC), Natcher of the House Appropriations Committee (HAC), and Murtha of the HAC Defense Subcommittee. Both SASC and HAC would normally "mark up" their versions of the Defense money bills after the House Armed Services Committee has had its shot at marking up -- but HASC is chaired by Ron Dellums, and HASC Research & Technology subcommittee is chaired by Patricia Schroeder, and they've been holding things up waiting for Clinton's long-promised gays policy. Nunn came on the Senate floor this morning and announced that SASC was marking up next week, and if Clinton didn't deliver a comprehensive gays policy, Nunn would put his own in. Regardless of the details of THAT brawl, Nunn says he's determined to have the Senate version of the Defense money bills settled before the August Congressional recess. Natcher too is said to have lost patience waiting on HASC -- Defense is the only money bill not already completed in the House. This means it's all likely to happen in the next two weeks, and much of the key stuff from our point of view will be settled by the end of next week. What this means for us is that we need to concentrate on Representative Murtha's HAC Defense Subcommittee and Senator Nunn's SASC *RIGHT NOW*. Our best current information is that Murtha's subcommittee will mark up Monday, and Nunn's full SASC will mark up Tuesday or Wednesday with no preliminary markup by Senator Exon's subcommittee. Representative Dellums's HASC and Representative Schroeder's HASC R&T Subcommittee could still be important to us, but they've dropped in priority for the moment. The initiative seems to have passed from them. SAS Recommended Action Please phone, fax, or write Representative Murtha and Senator Nunn, in addition to any members of Representative Murtha's HAC Defense Subcommittee that may be from your area, and any members of the Senate Armed Services Committee from your state. -- Representative John Murtha (D, PA) phone 202 225-2065, fax 202 225-5709, 2423 RHOB, Washington DC 20515. -- Senator Sam Nunn (D GA) phone 202 224-3521, fax 202 224-0072, US Senate SD303, Washington DC 20510. Lists of the other Representatives and Senators appended. Keep phone calls brief, polite, and to the point - tell whoever answers that you're calling to let them know you support fencing off $75 million of BMDO (formerly SDIO) funding for a followon to the Single Stage Rocket Technology ("SSRT") program. If you feel like it, throw in your favorite reason why this would be a good thing. If the person who answers wants to know more, answer their questions as best you can, otherwise thank them and ring off. Letters too should should be brief, polite, and to the point, though you can go into a bit more detail as to why a DC-X followon is the neatest thing since sliced bread and good for the country too. Keep it under a page and state your basic point at the start. It's probably too late to get snailmail to Murtha and company before their markup. Paper mail to Nunn and the SASC should be in the mail Saturday morning to have any hope of arriving on time. If you can, send faxes instead. Don't overdo it, but in general try to know who you're contacting and emphasize benefits likely to appeal to them. House Appropriations Committee, Defense Subcommittee List Name office# phone fax (AC 202) ("Representative XYZ", office#, "Washington DC 20515" will get mail to them) John Murtha (D-PA12) 2423 RHOB 225-2065 225-5709 Joseph McDade (R-PA10 RRM) 2370 RHOB 225-3731 225-9594 Jerry Lewis (R-CA40) 2312 RHOB 225-5861 225-6498 Charles Wilson (D-TX2) 2256 RHOB 225-2401 225-1764 Norm Dicks (D-WA6) 2467 RHOB 225-5916 226-1176 Martin Olav Sabo (D-MN5) 2336 RHOB 225-4755 225-4886 Julian Dixon (D-CA32) 2400 RHOB 225-7084 225-4091 W.G. Hefner (D-NC8) 2470 RHOB 225-3715 225-4036 Peter Visclosky (D-IN1) 2464 RHOB 225-2461 225-2493 Buddy Darden (D-GA7) 2308 RHOB 225-2931 225-0473 C.W. Bill Young (R-FL10) 2407 RHOB 225-5961 225-9764 Bob Livingston (R-LA1) 2368 RHOB 225-3015 225-0739 Joe Skeen (R-NM2) 2367 RHOB 225-2365 225-9599 Senate Armed Services Committee List Name office# phone fax (AC 202) ("Senator XYZ", office#, "Washington DC 20510" will get mail to them) Sam Nunn (D-GA) SD-303 224-3521 224-0072 James Exon (D-NE) SH-330 224-4224 224-5213 John McCain (R-AZ) SR-111 224-2235 224-8938 Richard C. Shelby (D-AL) SH-313 224-5744 224-3416 Joseph I. Lieberman (D-CT) SH-502 224-4041 224-9750 Bob Graham (D-FL) SD-241 224-3041 224-6843 Dirk Kempthorne (D-ID) 224-6142 224-5893 William S. Cohen (R-ME) SH-322 224-2523 224-2693 Edward M. Kennedy (D-MA) SR-315 224-4543 224-2417 Carl Levin (D-MI) SR-459 224-6221 224-1388 Dan Coats (R-IN) SR-504 224-5623 224-1966 Trent Lott (R-MS) SR-487 224-6253 224-2262 Bob Smith (R-NH) 224-2841 224-1353 Lauch Faircloth (R-NC) SH-716 224-3154 224-7406 Jeff Bingaman (D-NM) SH-524 224-5521 224-1810 John Glenn (D-OH) SH-503 224-3353 224-7983 Strom Thurmond (R-SC) SR-217 224-5972 224-1300 John Warner (R-VA) SR-225 224-2023 224-6295 Charles S. Robb (D-VA) SR-493 224-4024 224-8689 Robert C. Byrd (D-WV) SH-311 224-3954 224-8070 Henry Vanderbilt "Reach low orbit and you're halfway to anywhere Executive Director, in the Solar System." Space Access Society - Robert A. Heinlein hvanderbilt@bix.com "You can't get there from here." 602 431-9283 voice/fax - Anonymous ------------------------------ Date: Sat, 17 Jul 1993 02:42:10 GMT From: stephen voss <voss@cybernet.cse.fau.edu> Subject: DC-X Question Newsgroups: sci.space could someone send me a bunch of info on it so when I talk to my Senators office I dont sound like a complete moron. 1)What is it exactly in layman's terms 2)How much will it costr 3)Does it come with an 8 track player and a rear window defroster (ok just kidding about this one) ;-) but im serious about first two questions ------------------------------ Date: Sat, 17 Jul 1993 01:49:38 GMT From: Dave Michelson <davem@ee.ubc.ca> Subject: GPS - who, how,..... Newsgroups: sci.space In article <glh.16.0@aplcomm.jhuapl.edu> glh@aplcomm.jhuapl.edu (Gene Heyler) writes: > > [in reply to a poster from Australia...] > > How about subscribing to the monthly periodical GPSWorld? It is >probably the best source of what's currently going on in the industry. The last time that I checked, GPS World is only available to qualified subscribers within the United States. If this has changed, please let me know! -- Dave Michelson -- davem@ee.ubc.ca -- University of British Columbia ------------------------------ Date: 17 Jul 1993 01:47:08 GMT From: George William Herbert <gwh@soda.berkeley.edu> Subject: GPS in space (was Re: DC-1 & BDB) Newsgroups: sci.space In article <stephens.742851680@ngis> stephens@geod.emr.ca (Dave Stephenson) writes: >>AS for Delivering People, Ariane 4 is not certified for delivering >>people. it could be, i am sure alan has argued it could be made too, >>but it is not available as a reliable planning option. > >Couple of points. Ariane can reach any orbit from Guyana. It has >frequently launched into sun sync orbits (97 deg). The paylaod >drops of course. British Aerospace proposed a 4 man 'super >command module' to fly on the Ariane 44 back in 1987. Could have >taken 6 back to Earth as crew return vehicle. It got nowhere fast. >a. It was British, B. it was like something the Americans had done! >c. The french wanted Hermes! This would be the Multi-Role Capsule. I've got some of the papers describing it. Neat little package, all said. Arianne needed some reinforcement to fly it (the upper stage needs to be stiffened) and it needs to be man-rated, but otherwise a good design. It had really great mass margins in the design, was estimated to cost a reasonable amount, and would have been a great vehicle for station crew rotation in its 6-man configuration. ESA seemed to have the same fixation with Wings that NASA does, though ;-) That having been said, MRC is not a flyable design, short several billion $ or ECU in development. Arianne 4 isn't man-rated, though doing so would be pretty easy I think. And Arianne 4 doesn't have the strengthened upper stage needed. So MRC was a good "what-if" exercise, but isn't any good for planning now. -george william herbert Retro Aerospace ------------------------------ Date: 17 Jul 1993 01:48:04 GMT From: Celeste Sleeper <ecs@pathos.caltech.edu> Subject: HRMS: 25 Arecibo Target Stars Newsgroups: sci.astro,sci.space ----- My first attempt at posting this seems to have vanished. If this is not the first time you've seen this, my apologies. ---------- The following is a list of the 25 "target" stars that were observed at the Arecibo Observatory by NASA's High Resolution Microwave Survey Targeted Search. They were selected from lists of near-by and sun-like stars. The following criteria were applied to select the stars: 1. They must fall in the optimal declination range for Arecibo. This is roughly +8.5 degress to +28.5 degress. The closer to zenith the better, because the star would stay in the optimal observing range for longer. In general, we looked for stars that were going to be in the optimal range for more than an hour, but this was not always possible. 2. They should be spaced roughly an hour apart in right ascension. The observing plan called for an observation on a star to take about one hour. 3. The hour "blocks" chosen were based on the star picked to be observed first. The first star, #1020, was selected because it was roughly overhead at Arecibo and was also visible from the Goldstone telescope in California on October 12, 1992. While the Targeted Search observed star #1020 from Arecibo, the Sky Survey scanned a portion of the sky containing that star with the 34-m Venus Antenna at Goldstone. 4. This pretty well narrowed down what stars were available. In the cases of more than one possible star, distance was usually the determining factor: i.e. the closer, the better. The complete list of target stars is still in preparation and will be published later this year in a scientific journal. ARECIBO TARGET STARS -- 1992 HRMS Right Ascension Declination Star Catalogs Distance Apparent Spectral Target Epoch 1950 Epoch 1950 GL HD SAO Other Name Constellation (l.y.) Magnitude Type Number h m s d m s 1000 0 36 45 20 58 54 27 3651 74175 54 Piscium Pisces 34 5.85 K0 V 1001 1 39 47 20 1 36 68 10476 74883 107 Piscium Pisces 26 5.22 K1 V 1002 2 45 12 26 51 42 113AB 17382 75580 Aries 59 7.61 K1 V 1004 3 27 37 19 56 0 21663 93462 Taurus/Aries 72 8.32 G5 V 1005 4 40 29 27 35 54 176.2 29883 76728 Taurus 73 8.00 K3 V 1006 5 34 4 20 42 24 209 37124 77323 Taurus 58 7.67 G4 IV-V 1007 6 23 14 18 47 18 233AB 45088 95677 OU Gem. Gemini 49 6.76 K2 V 1009 7 51 59 19 22 30 292.1 64468 97359 Gemini 92 7.87 K6 V 1010 8 37 7 11 42 24 315 73667 98015 Cancer 64 7.64 K1 V 1011 9 9 34 15 11 54 337A 79096 98427 Pi 1 Cancri Cancer 72 7.25 K0 V 1012 10 20 3 15 35 54 89906 99091 Leo 82 7.28 G2 V 1013 11 51 59 19 41 24 452.3A 103432 99858 Leo 63 8.22 G6 V 1014 11 52 2 19 42 24 452.3B 103431 99861 Leo 63 8.43 G7 V 1015 12 16 32 11 24 0 GL Virg Virgo 21 13.81 M V 1016 13 14 22 17 17 0 505A 115404 100491 Coma Beren. 39 6.59 K1 V 1017 14 49 5 19 18 24 566AB 131156 101250 Xi Bootis A,B Bootes 22 4.70 G8 V/K4 V 1019 14 51 7 19 21 12 567 131511 101276 Bootes 38 6.02 K2 V 1020 16 10 58 13 39 36 615.1A 145958 102018 49 Serpens Serpens 63 7.36 G8 V 1021 16 26 41 18 31 6 627A 148653 Hercules 56 7.68 K3 V 1022 17 51 22 21 20 0 697 85511 Hercules 59 8.48 K5 V 1024 19 5 43 16 46 36 746 178428 104551 Aquila 55 6.07 G5 V 1025 20 38 29 19 45 12 797A 197076 106373 Delph./Vulp. 65 6.45 G5 V 1026 21 42 7 14 32 36 836.7 206860 107364 Pegasus 49 5.94 G5 V 1027 22 48 56 13 42 6 216259 108215 Wo9798 Pegasus 76 8.30 K4 V 1028 23 29 20 19 39 42 896AB EQ Peg A,B Pegasus 21 10.38 M4 V/M6 V Notes: HRMS Target Number is a temporary internal catalogue number. GL refers to the Gleise Catalog. Questions may be directed to either of the following: Celeste Sleeper ecs@phobos.caltech.edu Peter Backus peter_backus@qmgate.arc.nasa.gov -- Celeste Sleeper - aka Ciela Andar | "I'm not even sure which planet I'm on." ecs@phobos.caltech.edu | "Well, if there's a bright center to the Astronomy Grad. Student | universe, you're on the planet that it's Summer: NASA Ames HRMS Project | farthest from." --C3PO and Luke: SW ------------------------------ Date: Sat, 17 Jul 1993 04:03:03 GMT From: hathaway@stsci.edu Subject: Hubble, Why the hurry? Newsgroups: sci.space,sci.astro In article <16JUL199320284922@stdvax.gsfc.nasa.gov>, abdkw@stdvax.gsfc.nasa.gov (David Ward) writes: > In article <CA9F9F.Hs1@scr.siemens.com>, masticol@scr.siemens.com (Steve Masticola) writes... >>clarke@next1.acme.ucf.edu (Thomas L. Clarke) writes: >> >> As I understand it the recent Endeavour mission stayed up two >> more days [...] to provide the maximum amount of time >> to prepare for the upcoming Hubble repair mission in December. >> >> Why the hurry? >> >> Or are there factors of which I am unaware? >> >>In a word, yes. >> >>Hubble is running on only one gyro; two (maybe three?) others have >>failed. If the last gyro fails, it loses attitude control and starts >>to tumble. It'd then be unserviceable, as well as useless for >>observation. I'd think NASA would want to put in new gyros before that >>happens. >> >>- Steve (masticol@scr.siemens.com). > > HST had six gyros, I think two are "dead in the water" failed, one is > "still breathing, but I wouldn't bank on it" failed, and three are being > used for control. If there were another gyro failure, HST would tumble > only if they didn't use the "still breathing" gyro, and I'm aware that > HST tested out a zero-gyro safe-hold recently, with acceptable results. > That mode could keep the spacecraft reasonably stable for a capture event > in December. > > Otherwise, I'd have to agree: no-one wants to _have_ to resort to such > measures. > > David W. @ GSFC But is there any indication that we know the time-scale for another gyro failure? At least well enough to justify risking a possible worse disaster by rushing in haste? I remember the attitude of the crew for the deployment launch - they kept at the "What if? and What could go wrong?" mantra. And I am glad of that. Is there something more to the hurry than a vague feeling of 'get to it at all costs before something else happens'? Is there a time limit to a safe-hold that would justify risking rushing? Or is there a true perception of haste anyway? W. Hathaway ------------------------------ Date: 17 Jul 1993 01:31:06 GMT From: George William Herbert <gwh@soda.berkeley.edu> Subject: Lifting body spacecraft (HL-20?) Newsgroups: sci.space hack@guenevere (Edmund Hack) writes: >Dave Michelson (davem@ee.ubc.ca) wrote: >: Is there even a schedule for the HL-20? I was under the impression that it >: was effectively dead. What is its current status? >It may still be limping along in the advanced studies area at Langley, but it >is certainly on life support. Last I heard, it was back-burner but there was still a moderately sized team at Langley on it. I know one of them; Lance Bush, who was at ISU last year. He did a quick presentation on the design during the session. And tantalizingly told us that a contractor (sounded a lot like the Skunk Works from the description) had been invited to do a bid estimate on building some and had given numbers back which were "Real High". I don't know what that means. We never weaseled the number out of him... 8-) They still had a group of engineers working on it last I heard, but it's not going anywhere. The great station costing massacre has probably grounded HL-20 forever. -George William Herbert Retro Aerospace ------------------------------ Date: 17 Jul 1993 02:04:32 GMT From: George William Herbert <gwh@soda.berkeley.edu> Subject: Moon Cable/Beanstalk. Newsgroups: sci.space dietz@cs.rochester.edu (Paul Dietz) writes: >Moreover: if you had a material that was strong and light enough to >make these cables, it would also make a dandy ultralight composite >material, in which case launch vehicles would get much lighter. >Remember, the payload on an SSTO goes up quickly if you can use >lighter materials, so if SSTO is reasonably feasible now, it becomes >much more so when built with unobtainium. Well, do remember (and we've been talking about this on the space-tech mailing list, for those who just get the newsgroup) composite structures lose most of a fiber's strength by the time they're fully formed. Much stronger fibers don't have equivalently better properties once they are laid up, not porportionally. There's some loss in that. Some of the high-end carbon fibers are within an order of magnitude of strong enough, and if I read my design with composites book right some Silicon Carbide whiskers _are_ strong enough to build a beanpole or tether from... I'll double check that tonight, but some were showing much greater than million PSI failure strength if I recall it right. Don't bury tether concepts quite yet 8-) I would second the last couple of sentences of Paul's though; anything that's good for Tethers will be more good for rockets, and it's gonna take a lot of rocket flights before we can ever consider really building a tether, wether we do or not. -george william herbert Retro Aerospace ------------------------------ Date: 17 Jul 1993 02:09:53 GMT From: George William Herbert <gwh@soda.berkeley.edu> Subject: SOIL PRODUCTION ON MARS Newsgroups: sci.space In article <742806263.AA02023@cheswicks.toadnet.org> Steve.Schaper@f9.n8012.z86.toadnet.org (Steve Schaper) writes: >If one could just get Mars the right atmosphere, lichen don't need >soil, and many tundra species need very little. They will make soil. >You would want to seed the soil in many locations with soil bacteria, >then when the organic content is high enough, earthworms, etc. You're putting the car before the road system here; getting Mars the right atmosphere is about 95% energy and effort wise of the effort needed to terraform it. The plants will be the easy (if not necessarily simple) part. Ways to get Mars an atmosphere are indeed being looked at, see for instance various papers in the soon-to-be-published Case for Mars V proceedings and the Case IV and III proceedings (already on better library shelves everywhere ;-). Oh, darn, that reminded me, I have to get my final drawings and paper versions to the editors... time to go offline for a while. Ta ta... 8-) -george ------------------------------ Date: 17 Jul 1993 03:24:28 GMT From: David Fagan <daf@bbn.com> Subject: Why are meteor showers seasonal? Newsgroups: sci.space I'm sure the answer to this must be simple, but it's been nagging at me for a long time. Why do particular metor showers recur at the same time of year? The simple answer is that there is a cloud of asteroids in the earth's orbit which the earth passes thru at the same time each year. However, don't I have to assume that the asteroids are in solar orbit as well? In that case it seems unlikely that the earth would repeatedly encounter those asteroids at the same point in its orbit. The only answer that leaves me is that there is an asteroid belt (or many belts) which cross the earths orbit. I've never heard anything to this effect, however. I must be missing something. My endless gratitude to whomever can explain this to me. Dave Fagan daf@bbn.com ------------------------------ id ab26002; 16 Jul 93 21:07:59 EDT To: bb-sci-space@CRABAPPLE.SRV.CS.CMU.EDU Xref: crabapple.srv.cs.cmu.edu sci.space:67154 Path: crabapple.srv.cs.cmu.edu!fs7.ece.cmu.edu!europa.eng.gtefsd.com!howland.reston.ans.net!math.ohio-state.edu!cs.utexas.edu!not-for-mail From: Gene Heyler <glh@aplcomm.jhuapl.edu> Newsgroups: sci.space Subject: Re: GPS - who, how,..... Date: 16 Jul 1993 19:40:21 -0500 Organization: UTexas Mail-to-News Gateway Lines: 23 Sender: daemon@cs.utexas.edu Message-Id: <glh.16.0@aplcomm.jhuapl.edu> Nntp-Posting-Host: cs.utexas.edu Source-Info: Sender is really news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU In article <zuf.742791750@nella12.cc.monash.edu.au> you write:>From: zuf@nella12.cc.monash.edu.au (Mr J Zufi) >Subject: GPS - who, how,..... >Date: Fri, 16 Jul 1993 03:02:30 GMT >Thanks for listening - I'm after info about GPS, i.e. articles, >ftp sites, books, people-in-the-know, etc. > >Please post replies publicly as I know of a few other people >seeking similar info. > > How about subscribing to the monthly periodical GPSWorld? It is probably the best source of what's currently going on in the industry. - Gene ------------------------------------------------------- Gene A. Heyler Johns Hopkins Univ. Applied Physics Lab Bldg 24 Rm E131 Laurel, Maryland USA 20723-6099 Phone : (410) 792-5000 x 8664 InterNet : GLH@APLCOMM.JHUAPL.EDU ------------------------------ End of Space Digest Volume 16 : Issue 886 ------------------------------