Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_6/V12_653.TXT

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Subject: SPACE Digest V12 #653

SPACE Digest                                     Volume 12 : Issue 653

Today's Topics:
           Re: Powerful telescope for sale
       Re: Thanks from "star gazer...maybe"..Bob and 8 year old
              Galileo Update - 12/05/90
           Space Station Redesign Proposal
          Re: NASA Select coverage of Astro mission

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: 10 Dec 90 18:15:27 GMT
From: amethyst!organpipe!achilles.lpl.arizona.edu![e-mail]  (Matt Cheselka)
Subject: Re: Powerful telescope for sale

In article <[e-mail]> [e-mail] (Eric Tilenius) writes:
>
>                       POWERFUL 6" REFLECTING TELESCOPE
>                         EDMUND SCIENTIFIC NO. 85,086
>
>                                 * FOR SALE *
>                                * JUST $650! *
>
>This 6" reflecting telescope is wonderful for the serious amateur astronomer.
>It features:
>
>    - 6" parabolic mirror polished to within 1/4 wavelength of light
>        (that's accurate to within 0.0000055 inches!)
>
Folks, don't let numbers cloud your judgement.  0.0000055 inches = 1375
angstroms, which is ok, but not ideal.


>    - Clock drive / tracking motor to keep telescope oriented on
>        objects as the Earth turns.
>
>    - Will reveal faint stars to nearly 13th magnitude under
>        favorable conditions!

Very favorable...not too probable.  You have MAYBE one night a year that you can
see 13th with a 6"...but I guess I'm also to guy who questions the integrity of
seeing Stephans Quin. with a 90mm...but let's not start that again.
>
>    - 4' mirror housing (this is a big telescope!)
>
Can you explain this in better detail?


>    - Can split double stars separated by only .75 seconds of arc!

Under great seeing conditions...not too probable.  I really think that this
would be rather difficult with a 1/4 wave mirror...your sky would have to be
ROCK steady...maybe out in space.
>
>    - 1" focal length Kellner eyepiece
>    - 1/2" and 1/4" focal length Ramsden eyepieces

These two eyepieces are probably the worst eyepieces on the market...
my apologies to Kellner and Ramsden.  And who the heck still measures focal
lengths of eyepieces in inches?  Well, I guess it's just easier to understand
for all those suckers who will call to buy this scope.
>
>    - Mounted Barlow assembly w/ color corrected 2-element Barlow
>        lens of 46.6 mm focal length

What does this mean for a potential buyer?
>
>    - 6x sighting telescope

What about field of view and size of objective...another way to grab suckers by
only telling them how POWERFUL it is?
>
>    - Heavy-duty no-rust pedestal mount and weight mechanisms

How wobbly is it?  Can it withstand wind and heavy walking...you can't guide on
a star with your above mentioned  clock drive/tracking motor and take a long
exposure photo without the mount being steady.  How about polar alignment?  Is
that easy to do on this scope or is that unimportant to the sucker?
>
>    - PLUS BOOKS on how to use & get the most out of it, and more!
>
This is only good thing about this ad?

>Excellent condition!  A beautiful instrument!
>$650 includes everything listed above.

650 is actually a really good price...
>
>You must come and pick it up or arrange for pickup -- too tricky to ship!

Well, I don't know about that...I had mine moved down with me on a greyhound
bus!  It's CHEAP!

>Please CALL or EMAIL soon!
>


Eric, I'm not trying to make you loose a good deal on a good scope, but you
have to advertise reality and not just the high limits and possible expectations
about your scope.  I encourage anyone to buy this scope...it's a good beginners
instrument and having the books availiable will help a lot.  But PLEASE do not
buy this scope for the advertising!  I know it's sometimes fun to brag about a
scope and only note its good things, but there's good and bad about everything.
A good salesman will not be afraid to tell you that bad things about a product.
The person who only tells you about the good stuff is trying to rip you off.

Edmund Sci. stuff, i've noticed, is good quality...don't get me wrong.  But
bragging about 1/4 wave mirrors should be kind of embarrassing.  No flames
intended...i just wanted to let any possible buyer to not reguard this "ad" as
the final decision you should make...look into the instrument and the kinds of
things Eric talked about...make sure it's what you REALLY want.  I myself have
only looked through one Edmund Sci. 'scope, a few years ago...and I recall that
I liked it.  But i realy hate how people try to find suckers in the crowd to put that amount of money into something that they might regret later.

Buy the scope if you like what you hear in Eric's ad, but my recommendation
would be to explore the ideas of "wave" and Kellners and Ramsdens and Barlows that are color corrected and sighting scopes and telescope drives.  Ask me if
nothing else...I'll be happy to try and answer anything you want to ask.


Matt
Cheselka

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

Date: 8 Dec 90 16:45:56 GMT
From: alice![e-mail]  (Andrew Koenig)
Subject: Re: Thanks from "star gazer...maybe"..Bob and 8 year old

In article <[e-mail]> [e-mail] (Bob Egan) writes:

> Boom...Mars !!! wow...almost on top of us...never did figure out what
> that very small cluster of stars near it were...(I see them allot)

the Pleiades, perhaps?
--
                --Andrew Koenig
                  [e-mail]

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

Date: 11 Dec 90 04:21:27 GMT
From: snorkelwacker.mit.edu!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 12/05/90


                    GALILEO EARTH FLYBY STATUS REPORT
                           December 5, 1990

     The Galileo spacecraft will make an Earth gravity assist on December 8,
1990 at 12:34:34 PM (PST).  The spacecraft will approach the Earth from the
night side and make it closest approach over the Atlantic Ocean (25.2N
Latitude, 63.5W Longitude) at an altitude of 593 miles.  Galileo will make
numerous measurements of the Earth/Moon system before, during and after the
flyby.  Listed below are the science observations that will be made by each
of science instruments onboard the spacecraft.

     SOLID STATE IMAGING SYSTEM (SSI) - Provides high-resolution images in
the visible light with at 1500mm telescopic camera.  The sensor is an
actively-cooled, tantalum-shielded Charge Coupled Device (CCD) of 800 x 800
pixels.  Color pictures are obtained by combining images taken through
different filters.  The camera's best observations will detect objects as
small as 20 meters.  The SSI was checked out in December 1989 and had a
successful Venus encouter.  919 shutters and 120 filter wheel steps has
been performed since launch.  Earth flyby objectives:

     Earth:
     o Conduct ground truth studies and images system characterization.
     o Earth imaging to form movies:
        - "Powers-of-Ten" feature track movie.  Will start at 45 minutes
           Earth Closest Approach (ECA +45 minutes).
        - Zoom/Departure movie, will take images of the Earth after ECA
          and will continue to do for several days after ECA.
        - Spin movie, at ECA +2 days, 17 hours to ECA +3 days, 18 hours, will
          take images of one complete Earth rotation, which will be combined
          to form a spin movie.

     Moon:
     o Impact basin formation and evolution using the Orientale Basin.
     o Highland crustal heterogeneity.
     o Mare basalt distribution and characterization.
     o Nearside-farside asymmetries (maria and highlands).
     o Nature, origin and distribution of farside non-Mare volcanism.
     o South polar highlands and Mare crustal stratigraphy.
     o Physical characteristics of lunar surface via photometric study.

     DUST DETECTOR SUBSYSTEM (DDS) - Determines the velocity, mass, charge
and flight direction of sub-micron-sized particles.  Sensitive to dust
particle mass of 10^-16 grams to 10^-6 grams.  Up to 100 particles/sec
can be detected.  The DDS cover was deployed on December 27, 1989, and the
instrument was powered on December 28, 1989, and has remained on ever since.
Cruise science data has been recovered from 61 DDS memory readouts. Earth
flyby objectives:

     o Search for evidence of an Earth shepherded dust ring at 1 AU.
     o Investigate dust-magnetosphere interations (ie. swarms of dust
       particles) inside the magnetotail and magnetosphere.
     o Search for space debris inside 36,000 km and particularly at perigee.
     o Search for lunar ejecta while the Moon is within the field of view
       (mainly after closest approach).
     o Improve instrument calibration by characterizing the noise in each
       of the ion collector, electron collector and channeltron.

     MAGNETOMETER (MAG) - Monitors and measures magnetic fields for strength
and fluctuations in the spacecraft's immediate environment.  The MAG
instrument was first powered on October 19, 1989, and has remained on
continuously with the exception of the spacecraft safing event in January
1990 and the optimal averager anomoly in July 1990. Cruise science data has
been recoveredf from 49 MAG memory readouts.  On June 8, 1990, a storage
pointer was overwritten in the MAG executive program.  This was a result of
a programming error, and the problem has since been identified, and the
MAG memory was reloaded on August 6, 1990.  Earth flyby objectives:

     o High-time resolution magnetic field data (snapshots) will be taken
       during the bowshock crossing.  Multiple shock crossings are estimated
       between 2:35 PM (PST) and 3:05 PM on December 8, 1990.
     o MAG will look for ion cyclotron waves in unique frequency band
       bridging the gap between PWS data and other MAG data.
     o The structure and dynamics of Earth's distant magnetotail will be
       investigated.
     o Solar wind data will be correlated with IMP8 (Earth orbit) data to
       study the scale size of solar wind magnetic structures.

     ENERGETIC PARTICLE DETECTOR (EPD) - Measures in the spacecraft's
immediate environment the energy, composition, intensity and angular
distribution of high energy charged particles (electrons, protons and
heavy ions) having energies above 20keV and extending  to about 10MeV
per atomic mass unit.  The EPD was checked out in December 1989 and had
limited data at Venus.  Earth flyby objectives:

     o Measure electron and ion fluxes and ion composition (.02 to 55 MeV)
       in the distant geotail.  This extends the range of energy and
       composition measurements provided by ISEE 3.
     o Attempt to determine the neutral energetic particle distribution
       upstream of the magnetosphere.

     NEAR INFRARED MAPPING SPECTROMETER (NIMS) - Measures the thermal,
compositional and structural nature of its targets in infrared.  Checked
out in December 1989 and had a successful Venus operation.  Earth flyby
objectives:

     Earth:
     o Mespheric water content - relation to potential methane increases
       and noctilucent cloud occurrences.
     o Geological and biolgical mapping of Australia and Antarctica:
        - New Biological data in 3.5 hydrocarbon bands (C-H stretching).
        - Antactic snow reflectance data for climatology.
        - Geological remote sensing and ground truth.
     o Global mapping:
        - Spectral properties of vegetation.
        - Organic content of oceans and seas (phytoplankton).
        - Global distribution of atmospheric methane and organics.

     Moon:
     o Newly observed territory.
     o Search for hydrated minerals.
     o Extended phase angle coverage.

     ULTRAVIOLET SPECTROMETER (UVS) and EXTREME ULTRAVIOLET SPECTROMETER
(EUV) - Measures gases and aerosols and looks for complex molecules.  The
UVS has been on since a 4 day checkout on December 27, 1989, and has made
Venus observations and Lyman Alpha background surveys during cruise.  The
EUV was cross calibrated with the UVS in December 1989.  The EUV made Venus
observations, making ongoing sky background maps, and successfully observed
Comet Levy. Earth flyby objectives:

     o Obtain Lyman Alpha maps with 10 degree resolution over the entire
       anti-Sun hemisphere.
     o Search for possible lunar atmospheric constituents, ie. H, He, O, S
       OH.
     o Obtain H and OH maps of the entire Earth-Moon system.
     o Measure ozone abundance at various Earth latitudes.
     o Map the Earth's night airglow emissions NO. (2363), NO (1980) and
       altitude variations.
     o Map the Earth's geotail and magnetosphere from 250 R+ to 1 R+ in
       Lyman Alpha, He 584 Angstroms and O+ 834 Angstroms.
     o Search nightside to dayside exosphere for H, He and O+ emissions.
     o Map the interstellar wind and density profile for the He cone from
       7000 R+ to 250 R+.

     PHOTOPOLARIMETER RADIOMETER (PPR) - Observes light in the visible and
infrared wavelengths, provides data on atmospheric composition and thermal
energy distribution.  Operated at Venus, and recently turned back on.  Earth
flyby objectives:

     o Make polarization measurements over clear and cloudy regions of the
       South Pacific to test capability of cloud particle detection.
     o Measure the Earth's radiation budget to test PPR capability.
     o Map the polarized light from the Moon between phase angle of 20 to
       150 degrees to TEST PPR capabilities.

     PLASMA SUBSYSTEM (PLS) - Measures the composition, energy, temperature
density, and three dimensional distribution and bulk motions of low energy
plasma (ions) in the spacecraft's immediate environment.  The instrument's
range is from 1V to 50kV with 5 second temporal resolution.  The PLS was
checked out in December 1989 and had 4 hours operation at Venus.  Earth flyby
objectives:

     o Characterize the dynamics of the plasma environment in the Earth's
       magnetosphere.
     o First simultaneous measurements of both ion and electron flows to
       characterize current system.
     o First definitive measurement of plasma composition in the magnetotail
       to determine source of plasma.
     o Search for charged oxygen in plasmoids to discern plasmoid/plasma
       sheet association.

     PLASMA WAVE SYSTEM (PWS) - Detects electromagnetic waves and analyzes
wave-particles interactions in three dimensions.  Uses a dipole antenna
comprising of two 10 meter graphite-epoxy antennas at the tip of the
Magnetometer boom, and search coils in the High Gain Antenna reflector
structure.  The PWS was checked out in December 1989 and collected 1 hour
of Venus data.  Earth flyby objectives:

     o Characterize plasma waves and radio emissions in the distant
       magnetotail.
     o Obtain a complete set of low rate science plasma wave observations
       extending from the solar wind through the dawnside magnetosphere.
     o First wideband observations of both electromagnetic and electrostatic
       waves in the solar wind and Earth's magnetotail/magnetosphere.

      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 11 Dec 90 21:05:02 GMT
From: swrinde!cs.utexas.edu!samsung!uakari.primate.wisc.edu!sdd.hp.com!news.cs.indiana.edu!msi.umn.edu!cs.umn.edu!kksys!orbit!pnet51![e-mail]  (S Schaper)
Subject: Space Station Redesign Proposal

A proposal for the U.S./International Space Station:

 LLNL as the manned base for both testing biology at various g factors and
for housing the OMV, LMV's and Mars mission(s).

 A combination of Columbus, EOS and Freedom parts to produce the man-tended
free-flyer for both materials science and remote observations such as EOS
and ASTRO 1 payloads.

  This seems a usable synthesis that we know how to  build, and will
achieve the tasks that Freedom was originally intended for.

  Cost savings in the LLNL manned portion should make it possible to
re-implement the Manned Orbit Manuevering Vehicle(s).

     This should be neither as inexpensive as LLNL proposes, nor as
expensive as Freedom is predicted to be by its' detractors, and should
solve most, if not all, of the problems of both facilities in regards to
performing both as a manned exploration base camp and as a stable, zero-g
experiment platform.
**************************************************************************
Zeitgeist Busters!
UUCP: {amdahl!bungia, uunet!rosevax, chinet, killer}!orbit!pnet51!schaper
ARPA: crash!orbit!pnet51![e-mail]
INET: [e-mail]

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

Date: 8 Dec 90 17:59:38 GMT
From: [e-mail]  (Michael S. Gull)
Subject: Re: NASA Select coverage of Astro mission


    A long time ago, in a galaxy far, far away....
    The HUT team had t-shirts made up a couple of years ago with Jabba the Hutt sitting in the payload bay of the Columbia.....
    There's also been a few designs around with Astro, although I don't think there was ever a t-shirt made...

                        Mike

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

End of SPACE Digest V12 #653
*******************