Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_6/V12_716.TXT

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Subject: SPACE Digest V12 #716

SPACE Digest                                     Volume 12 : Issue 716

Today's Topics:
           Re: space news from Nov 5 AW&ST
             Heat loss through radiation
         NASA Headline News for 12/19/90 (Forwarded)
           Re: space news from Nov 19 AW&ST
              Galileo Update - 12/18/90
          Re: MIR lottery (erh sweepstakes)
              Ulysses Update - 12/18/90

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Date: 19 Dec 90 19:04:29 GMT
From: usc!elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!dali.cs.montana.edu!ogicse!emory!emcard!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Organization: Gannett Technologies Group
Subject: Re: space news from Nov 5 AW&ST
References: <[e-mail]>, <FGF^?1|@rpi.edu>, <[e-mail]>
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In article <[e-mail]> [e-mail] (Nick Szabo) writes:
>
>OSC and Hercules are the only U.S. aerospace companies since the
>Shuttle to development a totally new, successful orbital launcher.
>They did it for 1/50th (2%) of what it cost to develop the first Shuttle.
>Unlike the major Shuttle contractors, they have carried a loss on the
>project (in other words risked their own money) eying future commercial
>markets.  These are encouraging facts not gripes.   Sorry I sounded like
>such a sourpuss over such a happy event.  :-)

The fact that a little 400 kilo payload launcher cost 2% of what the
vastly bigger and more complex shuttle cost is, in itself, shocking.
What are the hard numbers on development costs?

Gary

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Date: Tue, 18 Dec 90 22:32:32 EST
From: John Roberts <[e-mail]>
Organization: National Institute of Standards and Technology
    formerly National Bureau of Standards
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
To: [e-mail]
Subject: Heat loss through radiation


>From: ogicse!unicorn![e-mail]  (james d. Del Vecchio)
>Subject: Re: A human being in vacuum

>    [e-mail] (Douglas S. Rand) writes:
>>Radiational cooling is pretty effective,  especially when
>>the surrounding black body temperature is 3 or 4 degrees K.  If the
>>person in the vacuum is in shadow they could probably freeze in just
>>a few minutes.  If they're in direct sunlight then they might boil on
>>one side and freeze on the other (lots of fun).
>        --------
>I don't have a clear idea of how that would work.  If the heat in your
>body isn't going _into_ something (like air), then where is it going?

As others have pointed out, heat loss would be through thermal radiation
into "infinity". The rate of heat loss can be roughly calculated:
   The formula for energy transfer per second through heat flow for a
   "black body" (ideal) radiator is E = k * (T^4 - T0^4), where T is the
   temperature of the radiating body in Kelvins, T0 is the temperature of
   the surroundings, and k is 5.6696E-8 W / (m^2 * Kelvin^4). Therefore, the
   heat loss to open space of a blackbody object at 98.6 F would be about
   520 W/m^2, at 40 F would be 335 W/m^2, at 0 F would be 240 W/m^2, and so
   on. I believe the effective radiating surface of a human body is about
   1 to 1.4 m^2, and that a human is capable of generating at least 750 W
   for short periods of time, probably 200-300 W for extended periods, and
   perhaps 75-100 W at rest. It would seem then, that heat loss would be
   a problem.

Mitigating factors:
 - The skin temperature is lower than the core body temperature, thus reducing
   heat loss somewhat.
 - If you were near a large warm object such as a spacecraft or a metal plate
   heated by the sun, then the solid angle of exposure to open space would
   be reduced, and again heat loss would drop.
 - You wouldn't be naked in space, or you'd better not be. Insulating
   clothing would reduce heat loss, as would the helmet material (transparent,
   but not at human thermal wavelengths).
 - Good reflectors make poor radiators, and vice versa. The above formula is
   for an ideal black, nonreflecting surface. You may have noticed that most
   manmade objects in space are painted brilliant white wherever possible.
   This reduces radiative heat loss in shadow, and also reduces heating in
   sunlight. (Most white surfaces actually have poor reflectivity at thermal
   infrared wavelengths, so the reduction in heat loss would not be too
   pronounced, but but I believe the energy in sunlight is mostly centered
   around near-visible wavelengths, so reduction of solar heating should be
   quite significant.) I suppose the underside of the Shuttle is black partly
   to help it radiate heat during atmospheric reentry.

Radiative cooling can be observed on the earth. Air (except for the greenhouse
gases) is not very good at blocking thermal infrared, so a clear night sky
allows the surface of the earth to radiate heat into outer space very
rapidly. (That's part of what makes amateur astronomy one of the coldest
sports. :-) A cloud layer tends to reduce the cooling effect. The air doesn't
radiate much infrared, so it may remain fairly warm while the surface gets
cold. This effect has traditionally been used in the Middle East to produce
ice even when the air temperature is above freezing.
     John Roberts
     [e-mail]

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Date: 19 Dec 90 20:53:49 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
Subject: NASA Headline News for 12/19/90 (Forwarded)
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             Headline News
Internal Communications Branch (P-2) NASA Headquarters

  Wednesday, December 19, 1990    Audio Service: 202 / 755-1788

This is NASA Headline News for Wednesday, December 19, 1990

A new Office of Exploration and a new Office of Human Resources will be
established within NASA, Administrator Richard H. Truly announced
yesterday in a holiday message to employees.  The creation of the two
new offices was a rapid response to recommendations made by the
Advisory Committee on the Future of the U.S. Space program.  Truly
noted that the initial duty of the Exploration Office would be to
provide "well thought-out" options to meet the challenges of returning
to the moon and and exploring Mars.  The Human Resources Office would
insure that NASA has the engineering, scientific and administrative
talent necessary to fulfill its civil space mission.  Truly also said
that NASA would place considerable emphasis on initiating the
committee's recommendation to develop a heavy lift launch vehicle and
to insure the robustness of the U.S. civil space transportation
system.


  * * * * * * * * * * * * * * * * * * * * * * * * * *

Fog in Texas and Louisiana delayed this morning's takeoff of the Space
Shuttle Columbia and its 747 carrier from Kelly AFB, San Antonio,
Texas.  Wheels up time for today's leg of the ferry flight to KSC was
9:44 a.m. Eastern time, with Barksdale AFB, Shreveport, Louisiana the
planned next stop.  A fly-over of the Johnson Space Center, Houston,
was also planned.  A weather front over the Florida panhandle make
arrival time at KSC uncertain, and the possibility exists that an
interim overnight stop at Eglin AFB, Florida, or at some other
appropriate location may occur, due to weather.

* * * * * * * * * * * * * * * * * * * * * * * * * * *

Test firing of a modified Space Shuttle main engine has been
tentatively rescheduled for 3:00 p.m. EST, Thursday, Dec. 20th, at
Marshall Space Flight Center.  Engineers said a problem with the test
facility's computer during the final countdown caused the postponement
of the test, originally scheduled for Tuesday afternoon, and they are
still trying to determine the exact cause of the difficulty.  The test
is the first of a series to better understand the internal operating
environment of the shuttle main engine.

* * * * * * * * * * * * * * * * * * * * * * * * * * *

At Kennedy Space Center, the Space Shuttle Discovery's right- hand OMS
pod has been installed and its plumbing and electrical connections are
being secured.  Installation of the Forward Reaction Control system is
scheduled for tomorrow evening.   Carbon brake modifications on
Atlantis are expected to be completed tomorrow.


Here's the broadcast schedule for Public Affairs events on NASA
Select TV.  All times are Eastern.  **indicates a live program.



Wednesday, 12/19/90

      12:00 noon    Administrator's holiday
            message to employees
      12:30 pm      The Year In Review
            from NASA Centers
       1:00 pm    **Galileo Press Conference from JPL
       6:00 pm      Replay of Administrator's holiday message and
            The Year In Review from NASA Centers

Thursday, 12/20/90

       11:30 am         NASA Update
    2:00 pm       **STS-35 Crew Post-Flight Press Conference from JSC




All events and times may change without notice.  This report is filed
daily, Monday through Friday, at 12:00 pm, EST.  It is a service of
Internal Communications Branch at NASA Headquarters.  Contact:
CREDMOND on NASAmail or at 202/453-8425.


NASA Select TV:  Satcom F2R, Transponder 13, C-Band, 72 degrees West
Longitude, Audio 6.8, Frequency 3960 MHz.

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Date: 18 Dec 90 03:46:33 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Organization: Sequent Computer Systems, Inc
Subject: Re: space news from Nov 19 AW&ST
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In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>...
>US and Canadian electric utilities discuss rapid development and launch of
>a solar-storm-warning satellite to help protect power-distribution networks
>against high solar activity.  The utilities fear possible repetitions
>of the 13 March 1989 storm, which plunged Quebec into a nine-hour blackout,
>nearly blacked out the entire US Eastern Seaboard as well, and caused
>serious malfunctions and significant equipment damage in many areas.
>A small satellite would be parked in a halo orbit around the Earth-Sun
>L1 point [where ISEE-3 was stationed for some years].  It would be
>quite simple, carrying a UCLA magnetometer and an LANL plasma analyzer.
>The utilities hope that it could be up by 1992, given rapid commercial
>development, launch on Pegasus, and commercial funding throughout.  The
>utilities hope that NOAA would contribute some money -- and indeed, both
>NOAA and the USAF are interested -- but government budgeting is too slow
>for the perceived urgent need.
>...

This is a great example of why lowering the entry-level costs of
space by a factor of 5 -- even if the cost/kg is higher -- is a good
business proposition.  All of a sudden, we are seeing new industries
emerge, in little niches here and there.   Solar storm warning was
previously a government monopoly for government purposes.  Now, companies
can afford to launch satellites to suit their own needs.  Over the long
term, IMHO the number of organizations with access to space will rise by
an order of magnitude due to Pegasus.   I predict that once consciousness
of cheap space access reaches the business community, we will be seeing
many more new, small industries like this one emerge.  Not all of these
will remain small.  Way to go OSC and Hercules!




--
Nick Szabo            [e-mail]
"For historical reasons, this feature is unintelligible"
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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Date: 18 Dec 90 20:48:15 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Organization: Jet Propulsion Laboratory, Pasadena, CA.
Subject: Galileo Update - 12/18/90
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                        GALILEO STATUS REPORT
                          December 18, 1990

     Yesterday, the Galileo spacecraft successfully completed a 5-degree
SITURN which resulted in the spacecraft leading the sun by about 2.5 degrees.
In addition to the SITURN, the scan platform calibration activity was
successfully performed.

     Today, the sequence memory load for TCM-9A (Trajectory Correction
Maneuver) will be sent to the spacecraft.  The TCM will be executed tomorrow
and it is designed to change the spacecraft's velocity by about 5.3 m/sec.

     The resetting of the CDS (Command Data Subsystem) critical controller 2A
POR (Power-On Reset) Telemetry indication will be performed today.  This action
was reported erroneously as being performed yesterday.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

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Date: 19 Dec 90 15:20:37 GMT
From: swrinde!zaphod.mps.ohio-state.edu!ub![e-mail]  (Maurice Volaski)
Organization: SUNY Buffalo
Subject: Re: MIR lottery (erh sweepstakes)
References: <9012181903.AA00726@tilde>, <[e-mail]>
Sender: [e-mail]
To: [e-mail]

Yesterday's New York Times carried an article on the sweepstakes. One
interesting statement made was that no one living in New York, Florida,
or Rhode Island was eligible for the flight for legal reasons.

Does any one know what law this is referring to?

Maurice Volaski

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Date: 19 Dec 90 18:56:18 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Organization: Jet Propulsion Laboratory, Pasadena, CA.
Subject: Ulysses Update - 12/18/90
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                          ULYSSES STATUS REPORT
                            December 18, 1990

     As of 9 AM (PST), December 17, 1990, the Ulysses spacecraft is
42,947,521 miles (69,117,336 km) from Earth, and 388,420,334 miles
(625,101,935 km) from Jupiter.  The spacecraft is traveling at 75,539 mph
(121,568 kph) relative to the Sun, and 34,970 mph (56,278 kph) relative
to the Earth.

     On December 17, a further Conscan operation was carried
out in telemetry Engineering Mode to make an accurate assessment of the
actual hydrazine fuel usage.  As Ulysses approaches Opposition, the Solar
Aspect Angle is reducing which is in turn reducing the solar energy acting on
the axial boom which is thought to be inducing the nutation-like motion.  The
axial boom will fall into complete shadow on about December 21.

     Routine operations have continued, with experiment monitoring and on
December 12 a matrix re-configuration of the BAM (Solar Wind Plasma experiment)
took place.  Since the DSN (Deep Space Network) was able to provide virtually
complete 24 hour coverage during this reporting period, no tape recorder
operations have taken place.

     On December 18, further radio science testing will be carried out.  On
December 19-20, a GRU (Cosmic Dust) noise test will take place.  Also on
December 20, a STO (Radio and Plasma Wave) PFR command uploading together
with radio science testing and KEP (Energetic Particles experiment)
re-configuration will occur.

     KEP re-configuration will continue on December 21.  The decision may be
taken to switch off the S-band downlink on December 21.  This will place the
spacecraft in the foreseen routine downlink configuration.

     Following the Nutation Investigation Team meeting on December 18 further
tests may be carried out to investigate the nutation-like behaviour.

     Since the DSN is able to supply almost complete telemetry coverage during
the next reporting period, tape recorder operations are not foreseen.  The
DSN performance has been nominal during the reporting period.  Extra support
has been provided to maximize on the amount of real-time data acquired.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

End of SPACE Digest V12 #716
*******************