Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.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 ; Fri, 30 Mar 90 02:09:17 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Fri, 30 Mar 90 02:08:42 -0500 (EST) Subject: SPACE Digest V11 #200 SPACE Digest Volume 11 : Issue 200 Today's Topics: Re: Brilliant Pebbles Re: Aurora = Strange Flash of Light? Space List: What Every Space Enthusiast Should Know Re: NASA Headline News for 03/29/90 (Forwarded) Re: Shuttle Escapes Scientists advance monitoring of global atmospheric temperatures (Forwarded) NASA Headline News for 03/29/90 (Forwarded) ---------------------------------------------------------------------- Date: Thu, 29 Mar 90 20:31:45 EST From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. Subject: Re: Brilliant Pebbles >From: zaphod.mps.ohio-state.edu!rpi!crdgw1!ge-dab!puma!andrew.ATL.GE.COM!jnixon@tut.cis.ohio-state.edu (John F Nixon) >Subject: Re: "Brilliant Pebbles" vs. "Smart Rocks" (was Re: Railgun ...) >>Whatever happened to the succinct, professional sounding "Smart Rocks"? >Different program, if I am not mistaken. There are several proposals, involving projectiles of different sizes and capabilities, and in different numbers. >Actually, I am proposing "Savant Sand" as an SDI weapon. When detecting an >attack, put several tons of suborbital sand, suitably positioned, in front >of the stuff coming your way. Sure, it puts some plutonium in the upper >athmosphere, but ..... :-) ;-) 8-) That would work if everything came at the same time. John Roberts "...in their megalomania they thought to make the roberts@cmr.ncsl.nist.gov very sand beneath their feet intelligent." - The Cyberiad, by Stanislaw Lem ------------------------------ Date: 29 Mar 90 05:34:40 GMT From: zaphod.mps.ohio-state.edu!samsung!munnari.oz.au!murtoa.cs.mu.oz.au!ditmela!yarra!jlw@tut.cis.ohio-state.edu (John Webb) Subject: Re: Aurora = Strange Flash of Light? In article , wmartin@STL-06SIMA.ARMY.MIL (Will Martin) writes: > > I've never seen any reference to an aurora producing something equivalent > to a "whole-sky flashbulb effect" which is what at least part of this local > light flash was. The color I saw was a cold blue-white, like a flashbulb, > (deletions) > > I'd like to learn more about auroras. Anyone have a favorite reference > they would cite? > I quote from William R. Corliss: Handbook of Unusual Natural Phenomena - (quote) ALL-SKY LIGHT FLASHES ... many well-verified observations of sudden flashes of light covering the entire sky exist. Such phenomena vary from a brilliant, electric-blue flash to a flickering purple one. Some unknown agency trips a planet-sized "flash cube," releasing considerable luminous energy. (unquote) Well, he might have been exaggerating somewhat, but the book is good for all this sort of thing. The quote is followed by examples and guesses. John jlw@yarra.oz.au ------------------------------ Date: Thu, 29 Mar 90 10:12:29 PST From: greer%utd201.dnet%utadnx@utspan.span.nasa.gov X-Vmsmail-To: UTADNX::UTSPAN::AMES::"space@andrew.cmu.edu" Subject: Space List: What Every Space Enthusiast Should Know Space List: What every Space Enthusiast Should Know A List of Numbers and Equations Relevant to Space Exploration courtesy Dale M. Greer Numbers 9.8 m/s^2 ( 10) -- Acceleration at surface of Earth (one g) 7726 m/s (8000) -- Earth orbital velocity at 300 km altitude 3075 m/s (3000) -- Earth orbital velocity at 35786 km (geosync) 6378 km (6400) -- Mean radius of Earth (Re) 1738 km (1700) -- Mean radius of Moon (Rm) 5.974e24 kg (6e24) -- Mass of Earth (Me) 7.348e22 kg (7e22) -- Mass of Moon (Mm) 1.989e30 kg (2e30) -- Mass of Sun (Ms) 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) Conversions 1.61 km / mi 0.0254 m / in 3.28 ft / m 0.3048 m / ft 1.467 fps / mph (or 88 fps = 60 mph, exactly) 0.447 m/s / mph 2.2 lb / kg (2.2 pounds-mass, that is) Equations Where d is distance, v is velocity, a is acceleration, t is time. For constant acceleration d = d0 + vt + .5at^2 v = v0 + at v^2 = 2ad General Gravity f = G m1 m2 / r^2 a = v^2 / r g = G Me / r^2 For circular Keplerian orbits, where u is gravitational constant, a is semimajor axis of orbit, P is period. v^2 = u/a P = 2pi/(Sqrt(u/a^3)) 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 acceleration of gravity, T is temperature, k is Bolztmann's constant. 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 (13000 m -- 40000 ft) = d0*.18 d@9 km ( 9800 m -- 30000 ft) = d0*.27 d@6 km ( 6500 m -- 20000 ft) = d0*.43 d@3 km ( 3300 m -- 10000 ft) = d0*.65 (Suggestions? Your favorite numbers, equations?) ------------------------------ Date: 29 Mar 90 20:43:56 GMT From: cdaf@iuvax.cs.indiana.edu (Charles Daffinger) Subject: Re: NASA Headline News for 03/29/90 (Forwarded) In article <46141@ames.arc.nasa.gov> yee@trident.arc.nasa.gov (Peter E. Yee) writes: o ----------------------------------------------------------------- o Thursday, March 29, 1990 Audio: 202/755-1788 o ----------------------------------------------------------------- o o This is NASA Headline News for Thursday, March 29....... o Saturday. o o On Capitol Hill yesterday, Dr. William Lenoir, Associate o Administrator for Space Flight, told a Senate subcommittee o dealing with space that NASA will rely heavily on automation and o robotics to reduce maintenance space walks by astronauts for o Space Station Freedom. Lenoir was responding to published o reports that were extremely critical of the space station o maintenance requirements and the need for extensive o extravehicular activity to service the station in orbit. Is it just me, or does this seem even more blatantly political than usual.. Didn't the preliminary draft of the report in question just come out last week? Can NASA, which usually works at such a snail's pace, really come back with a legitimate answer to the problems to be posed in the report within a week, and have it prepared for congress? Can we take all of the 'management hats' which are worn around NASA by the people who unfortunately make the decisions and collectively burn them? -charles -- Charles Daffinger >Take me to the river, Drop me in the water< (812) 339-7354 cdaf@iuvax.cs.indiana.edu Home of the Whitewater mailing list: whitewater-request@iuvax.cs.indiana.edu ------------------------------ Date: 29 Mar 90 18:11:34 GMT From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Shuttle Escapes In article <5A031C150F1A010F-MTABWIDENER*DXANDY@widener> DXANDY@WIDENER.BITNET writes: > [one-man reentry systems] > Are there any plans to equip Space Station Freedom with any kind of >rescue system? ... There is persistent talk about equipping the station with some kind of lifeboat. However, this will probably resemble either an Apollo capsule or a scaled-down shuttle orbiter. One of the major requirements for such a thing is rapid return of a seriously-ill astronaut, and that dictates at least a two-man lifeboat. -- Apollo @ 8yrs: one small step.| Henry Spencer at U of Toronto Zoology Space station @ 8yrs: .| uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 30 Mar 90 02:10:53 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Scientists advance monitoring of global atmospheric temperatures (Forwarded) Brian Dunbar Headquarters, Washington, D.C. March 29, 1990 Jim Sahli Marshall Space Flight Center, Huntsville, Ala. Phil Gentry University of Alabama-Huntsville RELEASE: 90-45 SCIENTISTS ADVANCE MONITORING OF GLOBAL ATMOSPHERIC TEMPERATURES An improved technique for potentially measuring global atmospheric temperature changes and possible global warming has been developed by scientists at NASA's Marshall Space Flight Center, Huntsville, Ala., and the University of Alabama in Huntsville (UAH). Dr. Roy Spencer, a Marshall scientist in the Earth Science and Applications Division, and Dr. John Christy, a research scientist at UAH's Johnson Research Center, evaluated temperature data gathered by the National Oceanic and Atmospheric Administration (NOAA) satellites since 1979 to monitor monthly temperature variations over the globe to a mean accuracy of 0.01 degree Centigrade, setting a standard against which future temperature trends will be measured. While future global temperature variations were not specifically addressed, the decade from 1979-1988 showed no net warming or cooling trend. The NOAA data had been used previously for localized weather forecasting, which involved only small portions of the data. By developing a 10-year data record with global coverage, Spencer and Christy have immproved upon the surface thermometer network currently used to monitor global temperature. Thermometers are largely restricted to populated areas, leaving the atmosphere over oceans essentially unmeasured. Earlier data used to support claims of global warming during the past 100 years have come from temperatures measured with these thermometers at the Earth's surface. While monthly temperature variations measured by the satellites showed poor agreement with the surface thermometer data, annual averages agreed much better. Nothing could be said, however, about the validity of any long term warming trend observed by thermometers before 1979, due to the relatively short satellite data record. The satellite data Christy and Spencer used came from microwave radiometers, developed by NASA, that each day measure the average temperature of the lowest 6 miles of the atmosphere over most of the Earth. By providing a precise record of monthly temperature changes over the Earth, this data will be extremely valuable in improving the understanding and prediction of climate changes. The most dramatic events recorded by the satellites were the 1983 and 1987 El Ninos, when unusually warm water in the tropical Pacific Ocean affected weather conditions worldwide. Similar effects are believed to have contributed to the 1988 drought over the United States. The two El Nino events caused global temperatures to rise more in a few months than might be forecast from several decades of "enhanced greenhouse warming," the researchers noted. Dramatic global coolings, such as that following the 1983 El Nino, were part of the unexpectedly large annual and seasonal global temperature changes observed during the 1980s. Spencer's and Christy's research will be published Friday in Science magazine. ------------------------------ Date: 29 Mar 90 17:42:13 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: NASA Headline News for 03/29/90 (Forwarded) ----------------------------------------------------------------- Thursday, March 29, 1990 Audio: 202/755-1788 ----------------------------------------------------------------- This is NASA Headline News for Thursday, March 29....... The Hubble Space Telescope is being installed in the payload bay of the Space Shuttle orbiter Discovery today. A decision was made to make the move after it was determined that tiny little winged insects, called midges, had been sufficiently swept up in Launch Pad 39-B's Payload Changeout Room. About 40 of the little creatures were trapped in special cages in the super-clean transfer area. During installation, pad technicians will make electrical and mechanical connections between the orbiter and the telescope. An interface verification test will be conducted Saturday. In other pad work, a controller will be replaced on engine # 3 in the next day or so. An internal circuitry problem was discovered late Tuesday. It will be necessary to remove the heat shield around the engine to do the replacement work. The Flight Readiness Review is scheduled to begin tomorrow and conclude Saturday. A firm launch date will be most likely be announced Saturday. The Jet Propulsion Laboratory says the Galileo spacecraft is operating very well. It's 74 million miles from Earth...72 millon miles from the Sun and traveling at a speed of 83-thousand miles per hour. Spacecraft computers are now controlling Galileo in its post-Venus flyby phase. Commands have been sent to do routine tasks and schedule several trajectory-correction maneuvers planned for the Venus-Earth cruise period. The corrections will make necessary changes to the flight path for the Earth gravity-assist encounter in December. On Capitol Hill yesterday, Dr. William Lenoir, Associate Administrator for Space Flight, told a Senate subcommittee dealing with space that NASA will rely heavily on automation and robotics to reduce maintenance space walks by astronauts for Space Station Freedom. Lenoir was responding to published reports that were extremely critical of the space station maintenance requirements and the need for extensive extravehicular activity to service the station in orbit. *************** ----------------------------------------------------------------- Here's the broadcast schedule for Public Affairs events on NASA Select TV. All times are Eastern. Wednesday, April 4..... 1:00 P.M. Television coverage begins of the launch of the DARPA sponsored Pegasus air-launched booster by the NASA B-52 aircraft. Takeoff from Edwards Air Force Base is scheduled for 2:00 P.M. Release at about 3:10 P.M. All events and times are subject to change without notice. ----------------------------------------------------------------- These reports are filed daily, Monday through Friday, at 12 noon, Eastern time. ----------------------------------------------------------------- A service of the Internal Communications Branch, NASA HQ. ------------------------------ End of SPACE Digest V11 #200 *******************