Date: Thu, 15 Dec 1988 03:43-EST From: space-tech-request@cs.cmu.edu To: "~/st/lists/stdigest" Subject: Space-tech Digest #18 [ Note: I'll be away for Christmas until the end of the month. -- Marc ] Contents: Andrew Higgins Re: Ram Accelerator Paul Dietz Re: Ram Accelerator Charles Brunow Query: interpreting data on gravitational anomalies Marc Ringuette space plane concepts Paul Dietz Re: space plane concepts Charles Brunow Re: space plane concepts Steve Abrams Lunar Polar Probe Information (250 lines) ------------------------------------------------------------ Date: Thu, 8 Dec 88 23:35:51 CST From: Andrew Higgins To: space-tech@CS.CMU.EDU From: dietz@cs.rochester.edu (Paul F. Dietz) > I recently read somewhere (on the net?) a report of a professor and > students that built a model ram accelerator. Anyonme remember this? You may be referring to the article "Impulsive Behavior" by Susan Sutphin in the April 1988 issue of _Space_World_ (Vol. Y-4-292 p. 18). This is certainly not a technical article, but it does give some good background information. A brief summary follows: Students at the University of Washington are working on a chemically propelled mass launcher. The project is headed by Professors Adam Bruckner and Abraham Hertzberg of the university's Department of Aeronautics and Astronautics. The vehicle is similar to the main body of a ramjet used in unguided missles. The vehicle travels through a stationary tube filled with premixed high pressure gaseous fuel and oxidizer. The vehicle carries no primary propellant of its own. According to Bruckner,"The concept is that we can accelerate a vehicle weighing several thousand kilograms up to about 10 kilometers per second using only chemical energy and readily available fuels." The project has produced a small scale model that uses a projectile weighing between 50 and 100 grams and achieves a velocity of 2,400 meters per second. They hope to increase this to 4,000 meters per second before having to move to a different facility. All design work is based on current technology. The university has signed a teaming agreement with Olin Corp. and has received a research grant from Langley Research Center to further the effort. Both Ames and Lewis Research Centers are showing interest. Bruckner, Hertzberg, and Bogdanoff currently have a number of patents pending. Also, according to the April 1988 issue of _Aerospace_America_, high velocity gun launch concepts were debated at the AIAA/Defense Advanced Research Projects Agency lightsat conference in Monterey CA, and at a similar conference at Utah State Univ. Someone may want to look into these. -- Andrew J. Higgins | Illini Space Development Society 404 1/2 E. White St apt 3 | a chapter of the National Space Society Champaign IL 61820 | at the University of Illinois phone: (217) 359-0056 | P.O. Box 2255 Station A e-mail: ahiggins@uxe.cso.uiuc.edu | Champaign IL 61820 "A fanatic is one who can't change his mind and won't change the subject" - Sir Winston Churchill ------------------------------ Date: Sat, 10 Dec 88 10:41:18 EST From: dietz@cs.rochester.edu To: ota+@andrew.cmu.edu Cc: space-tech@cs.cmu.edu Subject: Ram Accelerator > The paper I > have was published at the _37th meeting of the Aeroballistic Range > Association_, Quebec, Canada, 9-12 September, 1986. The paper has now appeared in a journal: AIAA Journal, 26(2) (Feb. 1988), pages 195-203. It is slightly different from the conference version, but does not report the most recent experiments that reached 2.4 km/s. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 10 Dec 88 00:06:14 UTC (Sat) From: texbell!loci!clb@cs.utexas.edu (Charles Brunow) To: space-tech@cs.cmu.edu In the "Astronomical Almanac", information about the gravitational anomalies of the moon are given something like ... > Gravity field of the Moon > > gamma = (B-A)/C = 0.0002278 C/MR^2 = 0.392 > beta = (C-A)/B = 0.0006313 I = 5552".7 = 1`32'32".7 > C[2,0] = -0.0002027 C[3,0] = -0.000006 C[3,2] = 0.0000048 > C[2,2] = 0.0000223 C[3,1] = 0.000029 S[3,2] = 0.0000017 > S[3,1] = 0.000004 C[3,3] = 0.0000018 > S[3,3] = -.000001 How does one interpret this information? Also, in the "Documentation for the Machine-Readable Version of the Catalogue of Stars Within 25 Parsecs of the Sun" there are fields labeled "box orbit parameters" and U,V,W components of space velocity. Can someone describe how this data is used? Any help appreciated. ------------------------------ Date: Tue, 13 Dec 1988 00:19-EST From: Marc.Ringuette@DAISY.LEARNING.CS.CMU.EDU To: space-tech@cs.cmu.edu Subject: space plane concepts You may have noticed the noises on sci.space about starting up a private project to build a space plane. I doubt that such a project could really be completed by this kind of group (I think it's REALLY HARD) but I like the idea of sketching out some concepts for a super-simplified space plane. We'll see how it goes. I was hoping to kick off discussion here on space-tech with a specific design, but I couldn't pry one out of Chuck or Joe, and I'm not quite up to it this week. If anybody can come up with a design with some numbers for the size, weight, and performance it might achieve, that would be great. Remember, we're aiming for low-tech, low-cost. Does anybody know what the specs for the Phoenix launcher are? How about other small, simple launchers? It would be interesting to have some data points for comparison. ==== Space-tech people who have expressed interest in this are: Chuck Brunow (texbell!loci!clb) Joe Beckenbach (joe@csvax.caltech.edu) I also set up a 'space-project' mailing list for people to use for this. To join, send mail to 'space-project-request@cs.cmu.edu'. You can join now, but it won't get rolling until early January. In the meantime let's use space-tech. Hi ho. ----------------------------------------------------------------------------- | Marc Ringuette | mnr@cs.cmu.edu | "Take me to your leader" | | CMU Computer Science | 412-268-3728(w) | -- watch this space for other | | Pittsburgh, PA 15213 | 412-681-5408(h) | quotes from great literature | ----------------------------------------------------------------------------- ------------------------------ Date: Tue, 13 Dec 88 09:20:23 EST From: dietz@cs.rochester.edu To: space-tech@cs.cmu.edu Subject: Re: space plane concepts It might be possible to build an amateur winged reentry vehicle, and piggyback it onto a commercial launch. Talk of building an amateur winged launch vehicle is, IMHO, a waste of time -- it'd be orders of magnitude too expensive and complicated. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 14 Dec 88 04:02:10 UTC (Wed) From: loci!clb@cs.utexas.edu (Charles Brunow) To: space-tech@cs.cmu.edu Subject: space plane concepts >You may have noticed the noises on sci.space about starting up a private >project to build a space plane. I doubt that such a project could really be >completed by this kind of group (I think it's REALLY HARD) but I like the >idea of sketching out some concepts for a super-simplified space plane. >We'll see how it goes. There you go again; you are the most pessimistic person I know. You have made no effort to demonstrate that this project cannot be achieved but you are constantly running it down. I'd like to hear some good reasons why you're so set against a net space plane. So far all I've heard is an incessant "It won't work" or "You're doing it wrong." How can you presume to speak for the people who are working on the project, to tell them that they aren't capable of succeeding? >I was hoping to kick off discussion here on space-tech with a specific >design, but I couldn't pry one out of Chuck or Joe, and I'm not quite up >to it this week. If anybody can come up with a design with some numbers >for the size, weight, and performance it might achieve, that would be great. >Remember, we're aiming for low-tech, low-cost. Space-tech is not suitable for this project; I sampled the contents of space-tech from the archives and determined that the general trend of the group is totally different from that which is needed. The people who are doing the actual work require there own private group; a mailing list serves to tie the group together but it must be private to restrict access on a need-to-know basis. The specific details have commercial value and cannot be protected without privacy. Of course you are free to proceed with your exercise however you wish. You'll have to do it without me though because the time required to write these postings can be channelled into the research/design/simulation instead, which I prefer. -- #_\_@\\/\_@\\/\_@\ Charles Brunow Loci Products # /--u// --u// --o/ clb@loci.UUCP POB 833846-131 # _ __ _ _ __ __ __ ..!uunet!texbell!loci!clb Richardson, Texas 75083 ------------------------------ Date: Fri, 9 Dec 88 07:42:55 CST From: sedspace@doc.cc.utexas.edu (405986289 abrams) Posted-Date: Fri, 9 Dec 88 07:42:55 CST To: SEDS-L%TAMVM1.bitnet@cunyvm.cuny.edu Subject: Lunar Polar Probe Information Cc: space-tech@cs.cmu.edu Gang, The following information was gleaned from handouts at the first three meetings of the Lunar Polar Probe group in Houston. For those who are interested in the Lunar Polar PRobe conference that this group is hosting -- information about this conference was posted earlier on the nets; if you need a new copy, send me a note -- this information will give you a better idea of what types of things have been discussed for this probe. If you have any ideas, comments, or suggestions, send them to me at: sedspace@doc.cc.utexas.edu Steve Abrams 10/7/88 Lunar Polar Orbiter Mission (ELV Launch) - LOM 002-A (11/26/88-The simplest and least expensive Lunar Polar Orbiter consists of a spin-stabilized satellite whose spin axis is perpendicular to the plane of the ecliptic throughout the mission. The simplest and least expensive experiment package for such a mission consists of those experiments which do not require any pointing to obtain global mapping data. Such instruments collect their data without requiring stepping mirrors or antennas to compensate for the varying nadir direction with respect to the satellite's spin axis. Of the some 20 experiments which can provide fundamental data required to characterize the Moon. These are listed below:) This limited duration (about 1 year), pre-cursor mission will provide total coverage global maps of the composition of the lunar surface layer and the moon's gravity and magnetic fields and data on its physical characteristics, structure, and tenuous atmosphere. The complete set of experiments, which will be carried out in order to fulIy exploit the scientific capabilities of this type of mission, is as follows (listed according to major mission objectives); 1) Gamma-ray spectrometer, 2) Neutron spectrometer, to obtain data on the elemental (U, Th, K, H, Al, Mg, Fe, Ti at 80 km resolution) composition of the upper most surface layer (the regolith) of the moon. These experiments will determine if water ice is present in permanently shadowed regions at the poles and provide global maps of the composition of the surface. The maps are required to understand the global distribution of the various petrological/selenochemical units and, hence, the evolution of the crust, the bulk composition of the crust and the Moon and if and where economically important mineral deposits occur. 3) X-ray spectrometer, 4) Visual-near-IR spectrometer, and 5) 5-20 micron-IR spectrometer, to obtain data on the mineralogical (Plagloclase, Orthopyroxene, Clinopyroxene, Olivine, Ilmenite, Glass at 500 m resolution) composition of the upper most surface layer (the regolith) of the moon. 6) Multi-spectral Imager (100 m resolutlon), to obtain data on the distribution of compositional units. 7) Stereo-Imager (100 m resolutlon), and 8) High-resolution Imager (20 m resolutlon), to obtain data on the distribution of compositional units, the topography, and the structure of surface features. 9) IR radiometer and 10) Micro-wave radiometer, to obtain data on the temperature and physical properties of the surface and the heat flow (50 km resolution) from the lunar interior. 11) Magnetometer, 12) Electron reflectometer, to obtain data on the local magnetic fields (up to a few 100 or perhaps a few 1000 gammas at the surface, but only up to a few gammas at orbital altitudes) of the surface, the temperature of the interior, the presence or absence of a small metallic lunar core, and the interaction of the moon with the solar wind and geomagnetic tail. These data will help determine the internal structure, thermal history, and bulk composition of the Moon, if the Moon had a magnetic dynamo active in its earlier history, and the origins of the local magnetic fields. 13) Solar wind experiment, 14) Gravity experiment (doppler tracking), to obtain data on density differences in the crust, on the internal density profile of the moon, and the presence or absence of a small metallic lunar core. These data will help determine the internal structure of the moon, the presence of near-surface gravity anomalies (which might be related to ore deposits), and improve the definition of the lunar gravitational model needed for better orbital predictions. 15) Radar altimeter, to obtain data on the size and shape of the moon and its surface topography 16) Radar sounder, to obtan data on subsurface layering (to a depth of a few km) in the moon, on tis topography and on the presence of water ice in the polar regions 17) Mass spectrometer, 18) Suprathermal ion detector, and 19) UV spectrometer, to obtaln data or, composition (at least He, H, 40Ar, 36Ar, CH4, NH3, C02), concentration, and dynamics of the tenuous lunar atmosphere, the sporadic release of 40Ar and other volatiles from the lunar interior into the atmosphere, the release of volatiles into the lunar atmosphere by the impact of carbonaxeous chondrite meteorites and comet remnants, and the interactlon of the solar wind with ions produced in the tenuous atmosphere by UV radiatlon. 20) Alpha particle spectrometer, to obtain data on the distribution of radon release sites (e.g., Aristarchus, Grimaldi, and the edges of the maria) and on the frequency of release of radon from the lunar interior by detecting alpha particles from radioactlve, radon gas and from radioactlve deposits of radon's decay product, polonium. These data will help define the areas of the Moon which are tectonically and possibly volcanically active. 21) Synthetic-aperature radar, to obtain high resolution radar imagery in the permanently shadowed areas of the polar regions where ice may have accumulated. Lunar Polar Orbiter Mission(s) (Ref. JPL 660-41, Rev. A, Mission Summary for Lunar Polar Orbiter, 1977; Contributions of a Lunar Geosciences Observer to Fundamental Questions in Lunar Science, Dept. Geo. Sci., Southern Methodist U., Dallas, 1986; Preliminary Sci. Rpts. for Apollo 14, 15, and 16, NASA SP's) Experiment Mass Power kbits/s volume kg w cm3 1) Gamma-ray 15 10 1.5 29x32x50 spectrometer (4 boom) 2) Neutron Special mode of operation of Gamma- spectrometer ray spectrometer 3) X-ray 11 10 0.3 20x20x40 spectrometer 4) Visual-near-IR 23 12 1.5, 3, 83x37x39 optics spectrometer 6, 12 20x25x13 electronics 5) 5-20 micron-IR 16 12 10 60x50x30 spectrometer 6) Multi-spectral Integrated into the Visual-near-IR spectrometer Imager 7) Stereo-Imager 11 15 5 20x20x12 optics 25x18x5 electronics 8) High-resolution 15 20 10 TBD Imager 9) IR radiometer 17 18 1 23x23x30 10) Microwave 10 10 0.2 100x60x20 antenna radiometer 1Ox30x40 11) Magnetometer 3 3 0.4 8x5x5 sensor 4 boom 22x11x15 electronics 12) Electron 5 5 0.3 20x20x20 reflectometer 13) Solar wind 6 13 0.1 31x28x35 experiment 14) Doppler 7 4 0.1 61 dia x 13 antenna Gravity 30x30x12 electronics experiment, relay sub- 28 TBD TBD TBD satelllte, or corner 3 0 0 40x30x20 reflector satellite, 15) Radar 17 28 1 100 dia antenna altimeter 120x60x10 electronics 16) Radar TBD TBD TBD TBD sounder 17) Mass 11 TBD TBD 30x32x23 spectrometer 18) Suprathermal 9 10 0.1 34x12x31 ion detector 19) UV 17 7 0.2 27000 spectrometer 20) Alpha particle TBD TBD TBD TBD spectrometer 21) Synthetic- TBD TBD TBD TBD aperture radar (The ?????'s indicate areas where the xeroxed copy were blanked out) Lunar Polar Orbiter Missions can be launched from Earth, from Earth orbit, from L1 or L2 Space Stations, or from a Lunar Polar Orbiting Space Station (though the LPO's should not be in co-orbits with the Space Statlon). Since the LPO is an early pre-cursor mission, it will probably be launched from Earth or from Earth orbit and, so, only these orbits will be considered here. All the above LPO experiments can be carried on one large orbiter or sub-sets of the experimentscan be carried on 2 or more smaller orbiters. The LPOs are 3-axis stabilized spacecrafts. As instrument technology advances, advanced LPOs ????? flown (see LOM - 006). In order to increase the resolution ????? measurements, an advanced LPO can be flown tethered to a L???? Orbiting Space Station (see LOM - 007). This would a????? collected from altitudes of only 5 to 10 km. The following data are for a single LPO mission experiments and launched from Earth using an expen????? LPO Orbital Elements Semimajor axis: 1838 km Altltude: 100 km Eccentricity: 0.005 Inclination: 96.4! Node w.r.t. Sun line: 57! Argument of periapsis: 147! Orbital Period: 117.89 min. LPO Characteristics (ELV Launch) Instruments Mass: 56 kg Power: 52 w kblts/s: 23 Volume: 1 m3 Orbiter (total) Mass: 1200 kg Power: 320 w kbits/s: 50 Volume: 20 m3 (stowed) ------------------------------ End of Space-tech Digest #18 *******************