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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 <[e-mail]>
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![e-mail]  (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
 [e-mail]   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![e-mail]  (John Webb)
Subject: Re: Aurora = Strange Flash of Light?

In article <[e-mail]>, [e-mail] (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  [e-mail]

------------------------------

Date: Thu, 29 Mar 90 10:12:29 PST
From: [e-mail]
X-Vmsmail-To: UTADNX::UTSPAN::AMES::"[e-mail]"
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: [e-mail]  (Charles Daffinger)
Subject: Re: NASA Headline News for 03/29/90 (Forwarded)

In article <[e-mail]> [e-mail] (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<  [phone]
[e-mail]
Home of the Whitewater mailing list:    [e-mail]

------------------------------

Date: 29 Mar 90 18:11:34 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Shuttle Escapes

In article <5A031C150F1A010F-MTABWIDENER*DXANDY@widener> [e-mail] 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 [e-mail]

------------------------------

Date: 30 Mar 90 02:10:53 GMT
From: trident.arc.nasa.gov![e-mail]  (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![e-mail]  (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
*******************