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Subject: SPACE Digest V12 #702

SPACE Digest                                     Volume 12 : Issue 702

Today's Topics:
           Galileo Update - 12/08/90 (Earth Flyby)
           Re: space news from Nov 19 AW&ST
           Re: space news from Nov 5 AW&ST
         Re: call for discussion - FAQ topics
         Re: call for discussion - FAQ topics
              space GIF pictures
             Re:  A human being in vacuum

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription notices,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 14 Dec 90 19:23:33 GMT
From: van-bc!ubc-cs!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 12/08/90 (Earth Flyby)


                             GALILEO STATUS REPORT
                                 EARTH FLYBY
                               December 8, 1990

     At 12:35PM (PST) the Galileo spacecraft made it closest approach to
Earth.  Galileo came within 597 miles of Earth and just 0.4 seconds
off the predited time.  The gravity assisted enabled to pick up an
additional 11,000 mph to its velocity relative to the Sun up to a speed
of about 78,000 mph.  Highlights of the day are listed below.

     Prior the ECA (Earth Closest Approach) at 12:01 AM, the NIMS (Near
Infrared Mapping Spectrometer) took a thermal map mosaic of crater Langrenus
in Mare Fecunditatis on the Moon, at phase angles of 136.6 to 133.2 degrees.
A long map mode was utilized to characterize instrument response.
Subspacecraft latitude was at -6.2 degrees and longitude was t 294.4 degrees
west.  The NIMS resolution was approximately 276 km.

     At 2:04 AM, the SSI (Solid State Imaging) camera obtain low-light level
images of the Moon in both earthlight and/or starlight for the purpose of
assessing the imaging system sensitivity as well as to search for the possible
presence of lunar volatiles.  The SSI also did some lunar multispectral
mapping to calibrate the SSI with "ground truth" from Apollo landing sites,
to map red spots and other non-mare volcanism, and to explore unmapped areas.

     At 3:15 AM, the NIMS mapped Mare Fecunditatis in the proximity of the
Messier crater at an approximate resolution of 206 km with phase angles of
122 to 126 degrees at one instrument mode.  An SSI frame was also taken
with a clear filter.

     At 4:21 AM, the UVS (Ultraviolet Spectrometer) instrument observed the
Earth's geotail to study the distribution of hydrogen atoms in the antisunward
direction.  The UVS measurements at H Lyman-Alpha are 16 times the
sensitivity of the EUV's (Extreme Ultraviolet Spectrometer).  They will be
cross-compared with simultaneous measurements with EUV.  The first geotail
observations were at 90 degrees cone and will slow slew from above to
equidistantly below the ecliptic plane at a slew rate of about 1 degree/minute
(290.82 microradians/second).  The second observation is performed by a
slow slew about the antisunward directions (180 degrees or as close as
allowed to 180 degrees cone) to 160 degree cone angle in constant clock.

     At 5:37 AM, the PPR (Photopolarimeter Radiometer) instrument made another
phase angle map of the lunar disk.

     At 5:55 AM, the NIMS made its fourth full map mosaic, this time on
Mare Tranquillitatis with a range of phase angles of 118 to 111 degrees,
utilizing full map modes (204 wavelenghts, Gain state=1).  The NIMS
resolution was at 194 km.  The next NIM thermal map occurred at 8:22 AM with
the mosaic centered on the southern portion of Mare Tranquillitatis in the
proximity of Maskelyne crater north of the Apollo 11 landing site, with
phase angles from 107.5 degrees to 96 degrees.  Three SSI frames were taken
using the clear filter.

     At about 9 AM, lunar periapsis occurred with the spacecraft 74,150 miles
from the Moon.  At 10:15 AM, the PPR made another lunar phase angle map.
At 10:19 AM, the PWS made a high resolution observation near the Earth's
plasmsphere using the 80 kHz wideband mode. At 10:30 AM, the UVS made its
second measurment of the Earth's geotail.

     At 10:52 AM, NIMS made another thermal map mosaic, this time along
the terminator and the highland south of Rima Ariadaeus in Mare
Tranquillitatis.  The SSI took two frames with the clear filter.

     At 11:15 AM, at about 1 hours 20 minutes before ECA, the star scanner
shutter was closed and the spacecraft's attitude was based on the
gyroscopes only.  The Magnetometer (MAG) was configured for calibration at
11:33 AM.  The MAG will be operated in 6 of its 8 different configurations
during the Earth 1 encounter.

     The PLS (Plasma) instrument was safed at 11:54 AM.  At 12:03 PM with
the spacecraft now only 9,512 miles from Earth, the NIMS recorded some
mesopheric water profiles derived from the night side limb scans.   Water
was observed in the tell-tale emissions in longspectrometer mdoe.  One
scan was acquired near the equater over the Indian Ocean, another near the
70 N latitude near USSR/Scandinavia.  The SSI simultaneously acquired
auroral imaging during the 70 N latitude scan with 5-10 km vertical
resolution.

     At 12:14 PM, the SSI made lightning and aurora observations which
was recorded on the tape recoder.  Communications was switched from
LGA-1 (Low Gain Antenna 1) to LGA-2.  UVS observation was made at
12:23 AM of the night airglow morpology and altitude variations of NO
gamma (236.3 nm) and NO delta (198.0 nm) emissions.  Altitudes started
at 1000 km and sampled down to the surface. The EUV made measurements to
search for emissions of H, He and O+ in the 50.0 to 125.0 region of the
spectrum starting in the exosphere on the nightside and ending in the
exosphere on the dayside.

     At 12:30 PM, the DSN (Deep Space Network) lost contact with the
spacecraft as expected, as Galileo passed out of view of the tracking
stations.  ECA occurred at 12:34:34 PM.  At 12:38PM and 12:56PM, the NIMS
made two more mesopheric water profiles over the equator of the Pacific Ocean.

     At 12:59 PM, the PWS made some more high resolution observations
of the near Earth plasmasphere.  The PLS made observations of the
magnetosphere to determine the composition and source of the near Earth
solar wind, and to search for ion beams, charged oxygen, helium and
other heavy ions.

     At 13:17 PM, the SSI took it first multispectral images of Australia
from the time it became visible near the terminator.  The SSI will continue
to take images of Australia until it rotated out of view over the limb.  These
images will be combine together to form an Earth feature track/zoom movie.

     At 13:20 PM, the PPR measured the polarization at three separate
wavelengths on the day side of the Earth.  The resulting mosaic will
provide the best chance of observing both clouds and ocean surfaces.

     At 13:33 PM, the NIMS made its first Moon observation since ECA,
centering across Sinus Medii east of the Murchison crater.  The SSI
camera took two frames with the green filter.

     The shutter of the star scanner was opened a 13:45 PM.  At 14:04 PM
the HIC (Heavy Ion Counter) instrument was enabled to measure solar flares
and cosmic rays.  The EUV was turned off.

     At 14:16 PM, the NIMS obtained a Nyquist-sampled map of Australia and
its surrounding water to calibrate the NIMS longmap spectra as well as
to obtain spacial distributions of various mineralogical and vegetation
types.  This map, the first of two Australia maps, concentrates on the
western half of Australia within 30 degress of the morning terminator with
spacial resolution of 35-50 km per nimsel.  The SSI acquired 4-color maps
"on the fly" during each observation.

     At 14:19 PM, the MAG starting taking measurements every 5 minutes for
about an hour to study the high freqency structure of the Earth's bow
shock, which the spacecraft crossed multiple times.

     At 14:34 PM, the PWS made observations using its 80 kHz wideband mode.
At 15:05 PM, the NIMS made its second Nyquist-sampled map of Australia, this
time concentrating on the eastern half some 60 degrees from the terminator.

     At 15:34 PM, the UVS starting making UNEWS (UVS North East West South)
scans to provide a valuable set of control data for comparison with the
data acquired during the UVS NIMS Antarctica Map, as well as provide several
swaths of data regarding ozone abundance over the Antarctic.  The North
South swath will start near the South Pole of the Earth and will be compared
with the Equatorial swath and the 55 degree latitude swath that may be
be observed in the ozone emissions.

     At 16:09 PM, the NIMS made its second lunar observation since ECA, and
eighth overall.  The mosaic was centered on Sammering crater (lattide =
0.5 degrees, W longitude = 8 degrees) and east of the Apollo 14 and 12 landing
sites.  Two SSI frames were taken with the clear filter.

     At 16:59 PM, the NIMS now focused it attention on Antartica by taking
a Nyquist-sampled map of Antartic ice and it surrounding water.  The SSI
acquired contigous 3-color maps with a spacial resolution of 85 km per pixel.
The second map was made by NIMS at 17:56 PM.

     At 19:23 PM, the NIMS made its ninth lunar observation, this time on
northwest poing of Montes Riphaeus in Mare Insularum south of the Apollo
12 landing site.  Using the long map mode with a phase angle of 56.4 degrees,
NIMS obtained it best lunar spectral map resolution (123 km).  The SSI
obtained 4 frames with the clear filter.

     At 19:44 PM, the NIMS obtained a lunar thermal map at 147 to 144 degrees
phase, over the Kastner crater in mare Smyhil.  The NIMS resolution is at
about 274 km.

     At 19:56 PM, the NIMS obtained its first Nyquist-sampled map for a Earth
global mosaic.  Comprised of 12 OAPELS over some 25 hours, this map will
cover 30N to 30S near Africa at a spacial resolution of 125 km per pixel.

     At 21:06 PM, the NIMS continued its Moon farside coverage by obtaining
a spectral map of Oceanus Procellarum between Euclides and Letronne craters
at a phase angle of 49 degree with 179 km resolution.  The NIMS obtained
the Earth global moscaic #2 at 21:28 PM. Mosaic #3 came at 22:11 PM and
mosaic #4 at 23:48 PM.

     At 23:34 PM, the NIMS made its 11th lunar observation on the area
of Hansteen and Billy craters in Oceanus Procellarum at a phase angle of 39.3
degrees with a resoltion of 188 km.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 14 Dec 90 15:33:28 GMT
From: zaphod.mps.ohio-state.edu!caen!dahm.engin.umich.edu![e-mail]  (Ken Sheppardson)
Subject: Re: space news from Nov 19 AW&ST

In article <[e-mail]> [e-mail] writes:
>In article <[e-mail]>,
>     [e-mail] (Henry Spencer) writes...
>
>>Space station designers trying to decide whether it is more important to
>>get started on the latest redesign or finish the enormously complex series
>>of preliminary design reviews on the last design.  NASA favors the latter,
>>on the grounds that much of it will not need to be re-done.  [Wanna bet?]
>
>A lot depends on how much of the PDR material covers components that would
>remain themselves intact (although moved around all over the place) after
>a redesign.  Some components will remain more-or-less intact, such as the
>photovoltaic arrays and the associated beta gimbals (unless something's
>happened in the project office I haven't heard about yet).  In those cases,
>you probably would want to get the PDR review done.  But I'd take my time
>and have one eye on redesign issues at the same time, just in case.
>
   The PDR concluded some time ago. The review in question is the ISPDR
   (Integrated Systems Preliminary Design Review) which looks at interface
   issues, overall system performance, etc. - the sort of things that would
   change significantly due to a configuration change. Individual components
   and subsystems were examined during the PDR.


===============================================================================
 Ken Sheppardson                                  Email: [e-mail]
 Space Station Freedom Advanced Programs Office   Phone: [phone]
 NASA Langley Research Center                     FAX:   [phone]
===============================================================================

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

Date: 15 Dec 90 19:10:50 GMT
From: usc!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: space news from Nov 5 AW&ST

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.  :-)

Didn't they start out with a guaranteed sale from DAPRA before the
thing was actually built? And they also had use of the B-52 from
DAPRA, didn't they?

Phil

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

Date: 14 Dec 90 18:00:14 GMT
From: zephyr.ens.tek.com!wrgate!mtdoom![e-mail]  (Dan Tilque)
Subject: Re: call for discussion - FAQ topics

[e-mail] (Jonathan Leech) writes:
>
>I'd like to propose some new FAQ topics. Perhaps with this as a starting
>point we can evolve a good set and get volunteers to write them up for
>Eugene's list.
>
>    - Current space legislation of import.

There's not as much posted in the way of questions asked on this as
there is lobbying for support.  I'm not sure that inclusion in an FAQ
will reduce that noticeably.

At any rate, this kind of info requires periodic update by someone with
a pipeline to the sources of change.  As a keeper of an FAQ for another
group (sf-lovers), I've avoided questions like this mostly because I
have no access to that kind of info, but also because I just don't have
the time to keep changing the list.  Things may change sufficiently
slowly in the space arena that it's not as much a problem (I doubt it,
though).

>    - Planetary probes (Larry Klaes did a nice one which I recall Eugene
>    posting in the past, it should still be available).

Eugene still posts it periodically, I believe.  It could use a better
internal organization, but that's a different issue.

>    - Sources for digitized HST etc. images, and explanation of why
>    digital data is not immediately available; ordering info
>    for the Voyager CD.

Amen to this.

>    More topics, suggestions, and so forth?

How about the effects of explosive decompression on the human body.


---
Dan Tilque    --    [e-mail]

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

Date: 14 Dec 90 19:22:56 GMT
From: rochester!sol![e-mail]  (Brian Yamauchi)
Subject: Re: call for discussion - FAQ topics

In article <[e-mail]> [e-mail] (Jonathan Leech) writes:

   In article <[e-mail]>, [e-mail]
   (Eugene N. Miya) writes:
   |>You can make it change.  Just discuss the changes on the net, then mail the
   |>resolution to me.

   I'd like to propose some new FAQ topics.

       - Sources for digitized HST etc. images, and explanation of why
       digital data is not immediately available; ordering info
       for the Voyager CD.

And related to this, how about a directory of net archive sites for
space images?  (GIFs, rasters, etc.)  Especially since every request
for such images is followed-up by a half dozen "me too"'s...
--
_______________________________________________________________________________

Brian Yamauchi                University of Rochester
[e-mail]        Computer Science Department
_______________________________________________________________________________

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

Date: 13 Dec 90 08:02:55 GMT
From: csn!tramp.Colorado.EDU![e-mail]  (CARLEY STEPHEN PETER)
Subject: space GIF pictures

Thanks

Steve

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

Date: 14 Dec 90 18:42:43 GMT
From: van-bc!ubc-cs!news-server.csri.toronto.edu!utgpu!cunews!micor!latour!atronx!orbit![e-mail]  (Walt Sullivan)
Subject: Re:  A human being in vacuum

>In article <[e-mail]> [e-mail] (james d. Del Vecchio) writes:
>Followups To: sci.space
>
>Someone posted that vacuum was an isulator.

Vacuum insulates against heat transfer via conduction, as in Thermos
bottles. It also prevents cooling via convection, since there is
nothing there.

>
>    [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?

Heat can be transferred by radiation, as well. Offhand, I can think of
three good examples - the Sun (93,000,000 miles of vacuum), an incandescent
light bulb above you, and, since I live in Ottawa, Ontario, Canada,
45 degrees north of the equator, windows. On clear winter nights, sitting
in a room heated to 70 degress F, the half of me facing a clear,
unobscured window gets very cold - trying to radiate heat to warm
the depths of space. On cloudy nights, I don't get nearly as cold.
I don't know how cold it gets where you are, but try this:
get two thermometers and place them 2 or 3 feet away from a window
on a clear, cold night. Place an opaque object between one thermometer
and the window. Wait. I'll bet the unobscured thermometer reads
lower.

>
>I don't understand the "3 or 4 degree K" outside temp.  How can it have
>a tempature if there's nothing there?   Do you just mean an imperfect vacuum
>where the particles hitting you are at 3-4 deg K?

That's the background microwave radiation left over from the Big Bang.

>I always had the idea that something being cold was only relavent if it was
>actualy touching you.  What's touching you in space?

That's only necessary for cooling via conduction.

--

    Walt Sullivan           ...!fts1!atronx!orbit!walt
                            Fido 1:163/109.4
    None of what I say is what my employer says, ever!

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

End of SPACE Digest V12 #702
*******************