Date: Tue, 2 Mar 93 11:02:23 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #255 To: Space Digest Readers Precedence: bulk Space Digest Tue, 2 Mar 93 Volume 16 : Issue 255 Today's Topics: How to power the LEO-moon space bus : ) Space FAQ 05/15 - References Space FAQ 06/15 - Constants and Equations Space FAQ 07/15 - Astronomical Mnemonics 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: 1 Mar 93 03:27:21 GMT From: Adrian Hassall Lewis Subject: How to power the LEO-moon space bus : ) Newsgroups: sci.space fcrary@ucsu.Colorado.EDU (Frank Crary) writes: >In article <1993Feb24.005220.15641@bsu-ucs> 01crmeyer@leo.bsuvc.bsu.edu (Craig Meyer) writes: >>"Moon rocks consist chiefly of minerals containing aluminum, calcium, iron, >>magnesium, oxygen, silicon, and titanium. Hydrogen, helium, and other gases >>are trapped in some of the rocks." >>I've been wondering if, along with building materials, some sort of propellant >>could be extracted from moon dirt. >>Oxygen (and therefore LOX) looks easy enough. >>The only thing on my list from the World Book that looks "worth >>burning" is Aluminum. Could it be burned quickly in some kind of powdered >>form? >It requires a little bit of work, but oxygen and aluminum are the primary >components in solid rocket fuels. >>When it comes to frieght runs back and forth from LEO to the moon, NUCLEAR >>PROPULSION SYSTEMS look like the way to go. A few Uranium spheres will take >>you a long way, along with a little hydrogen gas as a working fluid. As long >>as the thing never came back to earth, radiation wouldn't be nearly as >>much of a problem. >Given the elements available on the surface, oxygen might be a better >option: The specific impulse would drop to 25% of a hydrogen fueled >nuclear thremal rocket, and nasty corrosion problems might crop up, >but refueling on the Lunar surface would be very easy. > Frank Crary > CU Boulder Ah! Someone beat me to it. I have been thinking about this sort of thing for a while now. Unfortunatly, as someone else pointed out, the mass ratio is a bit steep. But then again, once the thing is in orbit and LLOX is available, does it really matter? As for the engineering, I think it would be _easier_ than for a LH2 NTR. Why? Simple, use zirconia as a coating for the fuel. From what I've read, zirconia and uranium/oxide have similar melting points and similar coefficents of thermal expansion. This would save having to use the exotic carbon based coatings that have been such a problem for the LH2 NTR's. ajax BTW, does anyone have any info about the DoD particle bed reactor that was recently announced? ------------------------------ Date: 28 Feb 93 17:27:48 GMT From: Jon Leech Subject: Space FAQ 05/15 - References Newsgroups: sci.astro,sci.space,sci.answers,news.answers Archive-name: space/references Last-modified: $Date: 93/02/28 22:17:54 $ REFERENCES ON SPECIFIC AREAS PUBLISHERS OF SPACE/ASTRONOMY MATERIAL Astronomical Society of the Pacific 1290 24th Avenue San Francisco, CA 94122 More expensive but better organized slide sets. Cambridge University Press 32 East 57th Street New York, NY 10022 Crawford-Peters Aeronautica P.O. Box 152528 San Diego, CA 92115 (619) 287-3933 An excellent source of all kinds of space publications. They publish a number of catalogs, including: Aviation and Space, 1945-1962 Aviation and Space, 1962-1990 Space and Related Titles European Southern Observatory Information and Photographic Service Dr R.M. West Karl Scharzschild Strasse 2 D-8046 Garching bei Munchen FRG Slide sets, posters, photographs, conference proceedings. Finley Holiday Film Corporation 12607 East Philadelphia Street Whittier, California 90601 (213)945-3325 (800)FILMS-07 Wide selection of Apollo, Shuttle, Viking, and Voyager slides at ~50 cents/slide. Call for a catalog. Hansen Planetarium (Utah) Said to hold sales on old slide sets. Look in Sky & Telescope for contact info. Lunar and Planetary Institute 3303 NASA Road One Houston, TX 77058-4399 Technical, geology-oriented slide sets, with supporting booklets. John Wiley & Sons 605 Third Avenue New York, NY 10158-0012 Sky Publishing Corporation PO Box 9111 Belmont, MA 02178-9111 Offers "Sky Catalogue 2000.0" on PC floppy with information (including parallax) for 45000 stars. Roger Wheate Geography Dept. University of Calgary, Alberta Canada T2N 1N4 (403)-220-4892 (403)-282-7298 (FAX) wheate@uncamult.bitnet Offers a 40-slide set called "Mapping the Planets" illustrating recent work in planetary cartography, comes with a booklet and information on getting your own copies of the maps. $50 Canadian, shipping included. Superintendent of Documents US Government Printing Office Washington, DC 20402 Univelt, Inc. P. O. Box 28130 San Diego, Ca. 92128 Publishers for the American Astronomical Society. US Naval Observatory 202-653-1079 (USNO Bulletin Board via modem) 202-653-1507 General 202-653-1545 Nautical Almanac Office (info on the Interactive Computer Ephemeris) Willmann-Bell P.O. Box 35025 Richmond, Virginia 23235 USA (804)-320-7016 9-5 EST M-F CAREERS IN THE SPACE INDUSTRY In 1990 the Princeton Planetary Society published the first edition of "Space Jobs: The Guide to Careers in Space-Related Fields." The publication was enormously successful: we distributed 2000 copies to space enthusiasts across the country and even sent a few to people in Great Britain, Australia, and Ecuador. Due to the tremendous response to the first edition, PPS has published an expanded, up-to-date second edition of the guide. The 40-page publication boasts 69 listings for summer and full-time job opportunities as well as graduate school programs. The second edition of "Space Jobs" features strategies for entering the space field and describes positions at consulting and engineering firms, NASA, and non-profit organizations. The expanded special section on graduate schools highlights a myriad of programs ranging from space manufacturing to space policy. Additional sections include tips on becoming an astronaut and listings of NASA Space Grant Fellowships and Consortia, as well as NASA Centers for the Commercial Development of Space. To order send check or money order made payable to Princeton Planetary Society for $4 per copy, plus $1 per copy for shipping and handling (non-US customers send an International Money Order payable in US dollars) to: Princeton Planetary Society 315 West College Princeton University Princeton, NJ 08544 DC-X SINGLE-STAGE TO ORBIT (SSTO) PROGRAM SDI's SSRT (Single Stage Rocket Technology) project has funded a suborbital technology demonstrator called DC-X that should fly in mid-1993. Further development towards an operational single-stage to orbit vehicle is uncertain at present; for considerably more detail on the SSRT program, get the document ames.arc.nasa.gov:pub/SPACE/FAQ/DeltaClipper by anonymous FTP or through the email server. HOW TO NAME A STAR AFTER A PERSON Official names are decided by committees of the International Astronomical Union, and are not for sale. There are purely commercial organizations which will, for a fee, send you pretty certificates and star maps describing where to find "your" star. These organizations have absolutely no standing in the astronomical community and the names they assign are not used by anyone else. It's also likely that you won't be able to see "your" star without binoculars or a telescope. See the back pages of Astronomy or other amateur astronomy publications for contact info; one such organization may be found at: International Star Registry 34523 Wilson Road Ingleside, IL 60041 This is not an endorsement of ISR. LLNL "GREAT EXPLORATION" The LLNL "Great Exploration", a plan for an on-the-cheap space station, Lunar base, and Mars mission using inflatable space structures, excited a lot of interest on the net and still comes up from time to time. Some references cited during net discussion were: Avation Week Jan 22, 1990 for an article on the overall Great Exploration NASA Assessment of the LLNL Space Exploration Proposal and LLNL Responses by Dr. Lowell Wood LLNL Doc. No. SS 90-9. Their address is: PO Box 808 Livermore, CA 94550 (the NASA authors are unknown). Briefing slides of a presentation to the NRC last December may be available. Write LLNL and ask. Conceptual Design Study for Modular Inflatable Space Structures, a final report for purchase order B098747 by ILC Dover INC. I don't know how to get this except from LLNL or ILC Dover. I don't have an address for ILC. LUNAR PROSPECTOR Lunar Exploration Inc. (LEI) is a non-profit corporation working on a privately funded lunar polar orbiter. Lunar Prospector is designed to perform a geochemical survey and search for frozen volatiles at the poles. A set of reference files describing the project is available in ames.arc.nasa.gov:pub/SPACE/LEI/* LUNAR SCIENCE AND ACTIVITIES Grant H Heiken, David T Vaniman, and Bevan M French (editors), "Lunar Sourcebook, A User's Guide to the Moon", Cambridge University Press 1991, ISBN 0-521-33444-6; hardcover; expensive. A one-volume encyclopedia of essentially everything known about the Moon, reviewing current knowledge in considerable depth, with copious references. Heavy emphasis on geology, but a lot more besides, including considerable discussion of past lunar missions and practical issues relevant to future mission design. *The* reference book for the Moon; all others are obsolete. Wendell Mendell (ed), "Lunar Bases and Space Activities of the 21st Century", $15. "Every serious student of lunar bases *must* have this book" - Bill Higgins. Available from: Lunar and Planetary Institute 3303 NASA Road One Houston, TX 77058-4399 If you want to order books, call (713)486-2172. Thomas A. Mutch, "Geology of the Moon: A Stratigraphic View", Princeton University Press, 1970. Information about the Lunar Orbiter missions, including maps of the coverage of the lunar nearside and farside by various Orbiters. SPACECRAFT MODELS "Space in Miniature #2: Gemini" by Michael J. Mackowski 1621 Waterwood Lane, St. Louis, MO 63146 $7.50 Only 34pp but enough pictures & diagrams to interest more than just the modelling community, I feel. Marco's Miniatures of Dracut, Mass. have produced a 1/144 Skylab in an edition of 500 & a 1/48 Lunar Rover (same scale as Monogram and Revell Lunar Modules) in a similar edition. Prices are $45 for Skylab, $24 for LRV. Check with them for postage etc. I have no connection with them, but have found their service to be good and their stock of rare/old kits *is* impressive. Prices range from reasonable ($35 for Monogram 1/32 scale Apollo CSM with cutaway details) to spectacular ($145 for Airfix Vostok). Four Star Collectibles P.O. Box 658 Dracut Mass 01826, USA. (508)-957-0695. Voyager, HST, Viking, Lunar Rover etc. kits from: Lunar Models 5120 Grisham Rowlett, Texas 75088 (214)-475-4230 As reviewed by Bob Kaplow: Peter Alway's book "Scale Model Rocketry" is now available. Mine arrived in the mail earlier this week. To get your own copy, send $19.95 + $2.50 s/h ($22.45 total) to: Peter Alway 2830 Pittsfield Ann Arbor, MI 48104 The book includes information on collecting scale data, construction of scale models, and several handy tables. Appendicies include plans for 3 sport scale models, a 1:9.22 D Region Tomahawk (BT50), a 1/40 V-2 (BT60), and a 1/9.16 Aerobee 150A (BT55/60). I've only begun to study the book, but it certainly will be a valuable data source for many modellers. Most vehicles include several paragraphs of text describing the missions flown by the rocket, various specs including "NAR" engine classification, along with a dimensioned drawing, color layouts & paint pattern, and a black & white photograph. The vehicles included are the Aerobee 150A, Aerobee 300, Aerobee Hi, Arcas, Asp, Astrobee 1500, Astrobee D, Atlas Centaur, Atlas-Agena, Atlas-Score, Baby WAC, D-Region Tomahawk, Deacon Rockoon, Delta B, Delta E, Gemini-Titan II, Iris, Javelin, Juno 1, Juno 2, Little Joe 1, Little Joe 2, Mercury-Atlas, Mercury-Redstone, Nike-Apache, Nike-Asp, Nike-Cajun, Nike-Deacon, Nike-Tomahawk, RAM B, Saturn 1 Block 1, Saturn 1 Block 2, Saturn 1B, Saturn 5, Scout, Standard Aerobee, Terrapin, Thor-Able, Titan III C, Titan III E, Trailblazer 1, V-2, Vanguard, Viking Model 1, Viking Model 2, and Wac Corporal. ROCKET PROPULSION George P. Sutton, "Rocket Propulsion Elements", 5th edn, Wiley-Interscience 1986, ISBN 0-471-80027-9. Pricey textbook. The best (nearly the only) modern introduction to the technical side of rocketry. A good place to start if you want to know the details. Not for the math-shy. Straight chemical rockets, essentially nothing on more advanced propulsion (although earlier editions reportedly had some coverage). Dieter K. Huzel and David H. Huang, "Design of Liquid Propellant Rocket Engines", NASA SP-125. NTIS N71-29405 PC A20/MF A01 1971 461p Out of print; reproductions may be obtained through the NTIS (expensive). The complete and authoritative guide to designing liquid-fuel engines. Reference #1 in most chapters of Sutton. Heavy emphasis on practical issues, what works and what doesn't, what the typical values of the fudge factors are. Stiff reading, massive detail; written for rocket engineers by rocket engineers. SPACECRAFT DESIGN Brij N. Agrawal, "Design of Geosynchronous Spacecraft", Prentice-Hall, ISBN 0-13-200114-4. James R. Wertz ed, "Spacecraft Attitude Determination and Control", Kluwer, ISBN 90-277-1204-2. P.R.K. Chetty, "Satellite Technology and its Applications", McGraw-Hill, ISBN 0-8306-9688-1. James R. Wertz and Wiley J. Larson (editors), "Space Mission Analysis and Design", Kluwer Academic Publishers (Dordrecht/Boston/London) 1991, ISBN 0-7923-0971-5 (paperback), or 0-7923-0970-7 (hardback). This looks at system-level design of a spacecraft, rather than detailed design. 23 chapters, 4 appendices, about 430 pages. It leads the reader through the mission design and system-level design of a fictitious earth-observation satellite, to illustrate the principles that it tries to convey. Warning: although the book is chock-full of many useful reference tables, some of the numbers in at least one of those tables (launch costs for various launchers) appear to be quite wrong. Can be ordered by telephone, using a credit card; Kluwer's phone number is (617)-871-6600. Cost $34.50. ESOTERIC PROPULSION SCHEMES (SOLAR SAILS, LASERS, FUSION...) This needs more and more up-to-date references, but it's a start. ANTIMATTER: "Antiproton Annihilation Propulsion", Robert Forward AFRPL TR-85-034 from the Air Force Rocket Propulsion Laboratory (AFRPL/XRX, Stop 24, Edwards Air Force Base, CA 93523-5000). NTIS AD-A160 734/0 PC A10/MF A01 PC => Paper copy, A10 => $US57.90 -- or maybe Price Code? MF => MicroFiche, A01 => $US13.90 Technical study on making, holding, and using antimatter for near-term (30-50 years) propulsion systems. Excellent bibliography. Forward is the best-known proponent of antimatter. This also may be available as UDR-TR-85-55 from the contractor, the University of Dayton Research Institute, and DTIC AD-A160 from the Defense Technical Information Center, Defense Logistics Agency, Cameron Station, Alexandria, VA 22304-6145. And it's also available from the NTIS, with yet another number. "Advanced Space Propulsion Study, Antiproton and Beamed Power Propulsion", Robert Forward AFAL TR-87-070 from the Air Force Astronautics Laboratory, DTIC #AD-A189 218. NTIS AD-A189 218/1 PC A10/MF A01 Summarizes the previous paper, goes into detail on beamed power systems including " 1) pellet, microwave, and laser beamed power systems for intersteller transport; 2) a design for a near-relativistic laser-pushed lightsail using near-term laser technology; 3) a survey of laser thermal propulsion, tether transportation systems, antiproton annihilation propulsion, exotic applications of solar sails, and laser-pushed interstellar lightsails; 4) the status of antiproton annihilation propulsion as of 1986; and 5) the prospects for obtaining antimatter ions heavier than antiprotons." Again, there is an extensive bibliography. "Application of Antimatter - Electric Power to Interstellar Propulsion", G. D. Nordley, JBIS Interstellar Studies issue of 6/90. BUSSARD RAMJETS AND RELATED METHODS: G. L. Matloff and A. J. Fennelly, "Interstellar Applications and Limitations of Several Electrostatic/Electromagnetic Ion Collection Techniques", JBIS 30 (1977):213-222 N. H. Langston, "The Erosion of Interstellar Drag Screens", JBIS 26 (1973): 481-484 C. Powell, "Flight Dynamics of the Ram-Augmented Interstellar Rocket", JBIS 28 (1975):553-562 A. R. Martin, "The Effects of Drag on Relativistic Spacefight", JBIS 25 (1972):643-652 FUSION: "A Laser Fusion Rocket for Interplanetary Propulsion", Roderick Hyde, LLNL report UCRL-88857. (Contact the Technical Information Dept. at Livermore) Fusion Pellet design: Fuel selection. Energy loss mechanisms. Pellet compression metrics. Thrust Chamber: Magnetic nozzle. Shielding. Tritium breeding. Thermal modeling. Fusion Driver (lasers, particle beams, etc): Heat rejection. Vehicle Summary: Mass estimates. Vehicle Performance: Interstellar travel required exhaust velocities at the limit of fusion's capability. Interplanetary missions are limited by power/weight ratio. Trajectory modeling. Typical mission profiles. References, including the 1978 report in JBIS, "Project Daedalus", and several on ICF and driver technology. "Fusion as Electric Propulsion", Robert W. Bussard, Journal of Propulsion and Power, Vol. 6, No. 5, Sept.-Oct. 1990 Fusion rocket engines are analyzed as electric propulsion systems, with propulsion thrust-power-input-power ratio (the thrust-power "gain" G(t)) much greater than unity. Gain values of conventional (solar, fission) electric propulsion systems are always quite small (e.g., G(t)<0.8). With these, "high-thrust" interplanetary flight is not possible, because system acceleration (a(t)) capabilities are always less than the local gravitational acceleration. In contrast, gain values 50-100 times higher are found for some fusion concepts, which offer "high-thrust" flight capability. One performance example shows a 53.3 day (34.4 powered; 18.9 coast), one-way transit time with 19% payload for a single-stage Earth/Mars vehicle. Another shows the potential for high acceleration (a(t)=0.55g(o)) flight in Earth/moon space. "The QED Engine System: Direct Electric Fusion-Powered Systems for Aerospace Flight Propulsion" by Robert W. Bussard, EMC2-1190-03, available from Energy/Matter Conversion Corp., 9100 A. Center Street, Manassas, VA 22110. [This is an introduction to the application of Bussard's version of the Farnsworth/Hirsch electrostatic confinement fusion technology to propulsion. 1500 Subject: Space FAQ 06/15 - Constants and Equations Newsgroups: sci.astro,sci.space,sci.answers,news.answers Archive-name: space/constants Last-modified: $Date: 93/02/28 22:17:37 $ CONSTANTS AND EQUATIONS FOR CALCULATIONS This list was originally compiled by Dale Greer. Additions would be appreciated. Numbers in parentheses are approximations that will serve for most blue-skying purposes. Unix systems provide the 'units' program, useful in converting between different systems (metric/English, etc.) NUMBERS 7726 m/s (8000) -- Earth orbital velocity at 300 km altitude 3075 m/s (3000) -- Earth orbital velocity at 35786 km (geosync) 6371 km (6400) -- Mean radius of Earth 6378 km (6400) -- Equatorial radius of Earth 1738 km (1700) -- Mean radius of Moon 5.974e24 kg (6e24) -- Mass of Earth 7.348e22 kg (7e22) -- Mass of Moon 1.989e30 kg (2e30) -- Mass of Sun 3.986e14 m^3/s^2 (4e14) -- Gravitational constant times mass of Earth 4.903e12 m^3/s^2 (5e12) -- Gravitational constant times mass of Moon 1.327e20 m^3/s^2 (13e19) -- Gravitational constant times mass of Sun 384401 km ( 4e5) -- Mean Earth-Moon distance 1.496e11 m (15e10) -- Mean Earth-Sun distance (Astronomical Unit) 1 megaton (MT) TNT = about 4.2e15 J or the energy equivalent of about .05 kg (50 gm) of matter. Ref: J.R Williams, "The Energy Level of Things", Air Force Special Weapons Center (ARDC), Kirtland Air Force Base, New Mexico, 1963. Also see "The Effects of Nuclear Weapons", compiled by S. Glasstone and P.J. Dolan, published by the US Department of Defense (obtain from the GPO). EQUATIONS Where d is distance, v is velocity, a is acceleration, t is time. Additional more specialized equations are available from: ames.arc.nasa.gov:pub/SPACE/FAQ/MoreEquations For constant acceleration d = d0 + vt + .5at^2 v = v0 + at v^2 = 2ad Acceleration on a cylinder (space colony, etc.) of radius r and rotation period t: a = 4 pi**2 r / t^2 For circular Keplerian orbits where: Vc = velocity of a circular orbit Vesc = escape velocity M = Total mass of orbiting and orbited bodies G = Gravitational constant (defined below) u = G * M (can be measured much more accurately than G or M) K = -G * M / 2 / a r = radius of orbit (measured from center of mass of system) V = orbital velocity P = orbital period a = semimajor axis of orbit Vc = sqrt(M * G / r) Vesc = sqrt(2 * M * G / r) = sqrt(2) * Vc V^2 = u/a P = 2 pi/(Sqrt(u/a^3)) K = 1/2 V**2 - G * M / r (conservation of energy) The period of an eccentric orbit is the same as the period of a circular orbit with the same semi-major axis. Change in velocity required for a plane change of angle phi in a circular orbit: delta V = 2 sqrt(GM/r) sin (phi/2) Energy to put mass m into a circular orbit (ignores rotational velocity, which reduces the energy a bit). GMm (1/Re - 1/2Rcirc) Re = radius of the earth Rcirc = radius of the circular orbit. Classical rocket equation, where dv = change in velocity Isp = specific impulse of engine Ve = exhaust velocity x = reaction mass m1 = rocket mass excluding reaction mass g = 9.80665 m / s^2 Ve = Isp * g dv = Ve * ln((m1 + x) / m1) = Ve * ln((final mass) / (initial mass)) Relativistic rocket equation (constant acceleration) t (unaccelerated) = c/a * sinh(a*t/c) d = c**2/a * (cosh(a*t/c) - 1) v = c * tanh(a*t/c) Relativistic rocket with exhaust velocity Ve and mass ratio MR: at/c = Ve/c * ln(MR), or t (unaccelerated) = c/a * sinh(Ve/c * ln(MR)) d = c**2/a * (cosh(Ve/C * ln(MR)) - 1) v = c * tanh(Ve/C * ln(MR)) Converting from parallax to distance: d (in parsecs) = 1 / p (in arc seconds) d (in astronomical units) = 206265 / p Miscellaneous f=ma -- Force is mass times acceleration w=fd -- Work (energy) is force times distance Atmospheric density varies as exp(-mgz/kT) where z is altitude, m is molecular weight in kg of air, g is local acceleration of gravity, T is temperature, k is Bolztmann's constant. On Earth up to 100 km, d = d0*exp(-z*1.42e-4) where d is density, d0 is density at 0km, is approximately true, so d@12km (40000 ft) = d0*.18 d@9 km (30000 ft) = d0*.27 d@6 km (20000 ft) = d0*.43 d@3 km (10000 ft) = d0*.65 Atmospheric scale height Dry lapse rate (in km at emission level) (K/km) ------------------------- -------------- Earth 7.5 9.8 Mars 11 4.4 Venus 4.9 10.5 Titan 18 1.3 Jupiter 19 2.0 Saturn 37 0.7 Uranus 24 0.7 Neptune 21 0.8 Triton 8 1 Titius-Bode Law for approximating planetary distances: R(n) = 0.4 + 0.3 * 2^N Astronomical Units (N = -infinity for Mercury, 0 for Venus, 1 for Earth, etc.) This fits fairly well except for Neptune. CONSTANTS 6.62618e-34 J-s (7e-34) -- Planck's Constant "h" 1.054589e-34 J-s (1e-34) -- Planck's Constant / (2 * PI), "h bar" 1.3807e-23 J/K (1.4e-23) - Boltzmann's Constant "k" 5.6697e-8 W/m^2/K (6e-8) -- Stephan-Boltzmann Constant "sigma" 6.673e-11 N m^2/kg^2 (7e-11) -- Newton's Gravitational Constant "G" 0.0029 m K (3e-3) -- Wien's Constant "sigma(W)" 3.827e26 W (4e26) -- Luminosity of Sun 1370 W / m^2 (1400) -- Solar Constant (intensity at 1 AU) 6.96e8 m (7e8) -- radius of Sun 1738 km (2e3) -- radius of Moon 299792458 m/s (3e8) -- speed of light in vacuum "c" 9.46053e15 m (1e16) -- light year 206264.806 AU (2e5) -- \ 3.2616 light years (3) -- --> parsec 3.0856e16 m (3e16) -- / Black Hole radius (also called Schwarzschild Radius): 2GM/c^2, where G is Newton's Grav Constant, M is mass of BH, c is speed of light Things to add (somebody look them up!) Basic rocketry numbers & equations Aerodynamical stuff Energy to put a pound into orbit or accelerate to interstellar velocities. Non-circular cases? NEXT: FAQ #7/15 - Astronomical Mnemonics ------------------------------ Date: 28 Feb 93 17:28:22 GMT From: Jon Leech Subject: Space FAQ 07/15 - Astronomical Mnemonics Newsgroups: sci.astro,sci.space,sci.answers,news.answers Archive-name: space/mnemonics Last-modified: $Date: 93/02/28 22:17:48 $ ASTRONOMICAL MNEMONICS (This is the last FAQ section posted to sci.astro) Gathered from various flurries of mnemonic postings on sci.astro. Spectral classification sequence: O B A F G K M R N S Oh Be A Fine Girl Kiss Me Right Now, Sweetheart. (a classic) O'Dell's Big Astronomical Fiasco Gonna Kill Me Right Now Surely Obese Balding Astronomy Found Guilty; Killed Many Reluctant Nonscience Students. Octopus Brains, A Favorite Gastronomical Kitchen Menu, Requires No Sauce Odd Ball Astronomers Find Generally Kooky Mnemonics Really Nifty Stuff Oh Big And Ferocious Gorilla, Kill My Roomate Next Saturday Oh Boy, A Flash! Godzilla Kills Mothra! Really Not Surprising! Oh Boy, An F Grade Kills Me On Bad Afternoons Fermented Grapes Keep Mrs. Richard Nixon Smiling On, Backward Astronomer, Forget Geocentricity; Kepler's Motions Reveal Nature's Simplicity Our Bad Astronomy Faculty Gets Killed Monday Oven Baked Ants, Fried Gently, Kept Moist, Retain Natural Succulence Overseas Broadcast: A Flash! Godzilla kills Mothra! (Rodan Named Successor) Overweight Boys and Fat Girls Keep Munching Only Bored Astronomers Find Gratification Knowing Mnemonics Oh Bloody Astronomy! F Grades Kill Me Order of the planets: Sun Mercury Venus Earth (Terra) Mars (Asteroids) Jupiter Saturn Uranus Neptune Pluto My Very Earnest Mother Just Served Us Nine Pizzas Mother Very Thoughtfully Made A Jelly Sandwich Under No Protest My Very Erotic Mate Joyfully Satisfies Unusual Needs Passionately Men Very Easily Make Jugs Serve Useful Nocturnal Purposes Man Very Early Made A Jug Serve Useful Noble Purposes My Very Educated Mother Just Showed Us Nine Planets My Very Eager Mother Just Showed Us Nine Planets My Very Exhausted Mother hAs Just Swept Up a Planetary Nebula Most Voters Earn Money Just Showing Up Near Polls My Very Educated Mother Just Served Us Nine Pizza-pies Many Viscious Elephants Made John, Suzy and Uncle Need Protection Solar Mass Very Easily Makes All Jupiter's Satellites Undergo Numerous Perturbations. Mein Vater erklaert mir jeden Sonntag unsere niedlichen Planeten (My Father explains to me every Sunday our nine planets) Man verachte einen Menschen in seinem Unglueck nie -- Punkt (Never scorn/despise a person in his misfortune/bad luck/misery -- period!) Colors of the spectrum: Red Orange Yellow Green Blue Indigo Violet ROY G. BIV (pronounce as a man's name) Richard Of York Gave Battle In Vain Read Out Your Good Book In Verse Galilean Satellite of Jupiter: Io Europa Ganymede Callisto I Expect God Cries I Eat Green Cheese I Embarrass Good Christians Ich erschrecke all guten Christen (I scare all good Christians) Saturnian Satellites MET DR THIP Miriam's Enchiladas Taste Divine Recently. Tell Her I'm Proud. (Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion, Iapetus, Phoebe) Uranian Satellites: MAUTO Mispronunciations Afflict Uranus Too Often My Angel Uriel Takes Opium (Miranda, Ariel, Umbriel, Titania, Oberon) NOTE: the remaining FAQ sections do not appear in sci.astro, as they cover material of relevance only to sci.space. NEXT: FAQ #8/15 - Contacting NASA, ESA, and other space agencies/companies ------------------------------ End of Space Digest Volume 16 : Issue 255 ------------------------------