Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_4/V11_494.TXT

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Date: Wed,  6 Jun 1990 01:45:49 -0400 (EDT)
Subject: SPACE Digest V11 #494

SPACE Digest                                     Volume 11 : Issue 494

Today's Topics:
               Re: Jupiter Sodium Cloud
          "CCD imagers in HST" from EE Times
               Van Allen Belts
          Re: DSN Reliability and Resources Question
               Re: HAWAII AND STAR WARS
         NASA Headline News for 06/05/90 (Forwarded)
           Payload Status for 06/05/90 (Forwarded)
            SPACE Digest V11 #489

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: Tue, 5 Jun 90 13:38 EDT
From: "CURATOR, B.U. DEPARTMENT OF ASTRONOMY" <[e-mail]>
Subject: Re: Jupiter Sodium Cloud

In response to:

*Date: 31 May 90 18:45:47 GMT
*From: thorin!homer![e-mail]  (Jonathan Leech)
*Subject: Re: Jupiter and Sodium Cloud......

*In article <[e-mail]> [e-mail] ("CURATOR,
* B.U. DEPARTMENT OF ASTRONOMY") writes:
*>Last November, a team of astronomers from Boston University went to McDonald
*>Observatory in Texas to image this cloud in "sodium light", which is easier
*>to image than sulfur or some of the other elements Io spews out.

*    Does this lie in one of the frequencies spewed out by the sodium
*lighting astronomers are opposed to?

*    Jon Leech ([e-mail])    __@/


The emission which was observed to be coming from the Jovian environment is
the neutral sodium D1,D2 doublet at 5890 and 5896 angstroms. Sodium lamps
emit light at these same wavelengths, hence their orange appearance. We
had enough trouble with the naturally occuring atmospheric sodium emissions
and any excessive sodium lamp interference would have made the observations
impossible. Fortunately, McDonald Observatory has minimal sodium light
pollution and so it was a good place to make observations at these
wavelengths.

Brian Flynn
Boston University
Department of Astronomy

P.S. Thus another example of why we continually fight for dark skies! - FFS

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

Date: 5 Jun 90 22:18:28 GMT
From: mtndew![e-mail]  (Stephen J. Friedl)
Subject: "CCD imagers in HST" from EE Times

From _EE Times_, 4 June 1990, pg 33  (reproduced w/o permission)

    TI CCD Imagers Give Hubble Better Vision - Greenbelt, MD

    The first image returned from the Hubble Space Telescope
    was matched with a similar image from a telescope in Chile,
    and proved to be distinctly clearer.

    Texas Instruments supplied the thermoelectrically-cooled
    CCD imager arrays on the Hubble; they are set up in four
    tiled, 2048x2048 pixel imagers.

    Ground-based observatories have telescopes based on lower
    quality (fallout) CCD imagers, also often supplied by TI.

--
Stephen J. Friedl, KA8CMY / Software Consultant / Tustin, CA / 3B2-kind-of-guy
[phone]  / [e-mail]  / {uunet,attmail}!mtndew!friedl

"I will defend to your death my right to my opinion" - me

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

Date: Tue, 5 Jun 90 08:10:32 PDT
From: [e-mail]
X-Vmsmail-To: UTADNX::UTSPAN::AMES::"[e-mail]",HAIRSTON
Subject: Van Allen Belts

Today's (June 5) New York Times has a good article about the Van Allen Belts
, the South Atlantic Anomaly, and all the problems they're causing for NASA
and various satellites.  Check it out.  I'm still digging for a list of
articles about the belts and the magnetosphere in general and I'll post
that at the end of the week.

Marc Hairston--Center for Space Sciences--University of Texas at Dallas
SPAN address  UTSPAN::UTADNX::UTD750::HAIRSTON

"It is better to light a single candle than to get all hot and sweaty trying
to light a grape."--C. Barsotti

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

Date: 5 Jun 90 05:10:44 GMT
From: unmvax!nmt.edu![e-mail]  (Daniel Briggs)
Subject: Re: DSN Reliability and Resources Question

In article <[e-mail]> [e-mail] (S. Khai Mong) writes:
>A bunch of simple questions:
>What are the resources of DSN in terms of dishes and sites?
>
>What is the expected reliability and redundancy during really critical
>periods?
>
>Could radio astronomy telescopes be pressed into service?

Yes, they can and have used existing radio astronomy sites to
supplement the DSN.  Since the decodable bit rate that you can sustain
is a direct function of the sensitivities of your receiver, (at least
in the low signal case, anyway), more collecting area directly
translates into more pictures.  This was critical during the Voyager
encounter with Neptune.  The DSN was augmented with the VLA here in
New Mexico, and with the Parkes 64m telescope in Australia.  From our
point of view, it was a terrific deal!  NASA provided us with the
equipment that we needed to track Voyager, and we provided them with
about a month of observing time.  We got about $8M worth of new
equipment, and they got about 30% more images back than they would
have without us in the net.  Both sides proclaimed themselves
*extremely* pleased with the results.  With budgets the way that they
are, there is no way that we could have afforded half the stuff that
NASA bought us, some of it very badly needed indeed.  The reliability
issue is kind of interesting, though.  NASA has very different
standards of reliability than we do.  We had been running at about 80%
reliability or thereabouts before the encounter.  (Memory is vague, so
don't take this as gospel, but I think that was 80% of the time we
were *supposed* to be on the air.  That is, scheduled down time wasn't
included in that figure.)  NASA wanted the reliability above 98%.
That costs a lot of money that we just didn't have by ourselves.  I
mean, if we have a lightning strike and lose an hour of observing, we
just reschedule.  If that happens to the DSN during an encounter, you
are big time SOL.  Of the $8M that was spent on the upgrade, a little
less than half went to buying a new receiver system that could receive
Voyager.  (This X-band system is now the most sensitive of the half
dozen bands that we have available.  There is a *lot* of good science
that has come out of it.  Not the least is the fact that we now share
a frequency with Goldstone.  We can now do radar reflection
experiments with them.  They transmit, we receive.)  They remaining
money all went into upgrading our reliability.  We got a first class
lightning protection system for the control building.  We got a brand
new set of online control computers.  They brought in a few very
pricey specialists who managed to fix a few software bugs that had
been with us as long as the array has been operational.  We got not
one, but two new backup power generators.  Neither NASA's way of
operating not ours is *wrong*, but both are quite *different* from
each other.  The operating philosophies evolved under an entirely
different set of constraints.  In our case, maximizing the science per
buck meant more equipment, but less reliability.  NASA goes the other
way.  Certainly by the time they had finished the upgrade, we felt a
little Au plated.  (And even though I expect a few snide remarks about
that last sentence, I found the encounter to be a quite educational
experience.  Gold plated toilets are one thing, but reliable receivers
are another.  Reliability is expensive, but there are very good reasons
for making single point failure equipment as reliable as possible.  In
short, I could see where NASA was coming from during all of this.)


--
This is a shared guest account, please send replies to
[e-mail] (Internet)
Dan Briggs / NRAO / P.O. Box O / Socorro, NM / 87801  (U.S. Snail)

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

Date: 4 Jun 90 15:29:53 GMT
From: att!watmath!watserv1!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: HAWAII AND STAR WARS

In article <[e-mail]> [e-mail] (Doug Borsom) writes:
>The fact (if true) that Cape Kennedy includes a thriving wildlife
>refuge is irrelevant to the Hawaii question unless the two
>eco-systems are very similar and the proposed use (in the largest
>sense of the word) of the Big Island site is very similar...

You're confusing proofs with good examples.  The fact that Kennedy Space
Center (there is no Cape Kennedy nowadays) includes a thriving wildlife
refuge (it does; I've been there) is not sufficient to prove that the
Hawaii launch site would have similar results.  However, it *is* quite
sufficient to shoot down the claim that vast ecological devastation
would inevitably ensue.

>So far, most postings on both sides have dealt with the assesment
>of the ecological impact with the kind of simplicity that ...
>well, let's say that Carl Sagan has been accused of in writing
>his Sunday Supplement articles about subjects far outside his area
>expertise.

Subject to constraints of honesty and good taste, one does one's best to
match the tone and intellectual respectability of the original posting.
--
As a user I'll take speed over|     Henry Spencer at U of Toronto Zoology
features any day. -A.Tanenbaum| uunet!attcan!utzoo!henry [e-mail]

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

Date: 5 Jun 90 16:27:00 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 06/05/90 (Forwarded)

-----------------------------------------------------------------
Tuesday, June 5, 1990                Audio Service:  202/755-1788
-----------------------------------------------------------------
This is NASA Headline News for Tuesday, June 5........

Kennedy Space Center workers are preparing the Space Shuttle
Columbia with sensors for an additional test to find the source
of a liquid hydrogen leak that scrubbed last week's launch of
STS-35.  A liquid hydrogen fill test on the orbiter's main
propulsion system is scheduled for Wednesday morning.
Technicians hope to detect the leak source during the transition
from slow to fast fill. The orbiter will remain at launch pad 39-
A and the Rotating Service Structure will be retracted during the
test.
                            ********

The Magellan spacecraft is performing well in cruise mode
following the successful completion of a cruise mapping test last
Friday.  On completion of the final "orbit" of the mapping test,
the radar was turned off and the spacecraft subsystems were
returned from orbital operations to cruise configuration.  The
spacecraft is 108 million miles from Earth traveling at 76,000
miles per hour.  It is scheduled to reach Venus this August.

                            ********

Aerospace Daily reports an Administration official confirmed that
Vice President Dan Quayle met with Soviet leader Mikhail
Gorbachev Friday to discuss space.  The story reports the
National Space Council, chaired by Quayle, is drafting the scope
of international participation in the President's Space
Exploration Initiative.  According to the story, offers to
participate in missions to the moon and Mars will be extended to
Japan and European countries already involved in cooperative
space programs with the U.S., but Soviet participation will not
be ruled out.
                            ********

Japan's Agency of Industrial Science and Technology may build a
robot for Space Station Freedom, according to Reuters news
service.  The Japanese government will decide this August whether
to develop, build and launch a $130 million mechanical "handyman"
scheduled for the year 2000.  The robot would be used to assemble
structures and repair machinery in space.

                            ********

A second Pegasus launch by Orbital Sciences Corporation is
scheduled for early this fall, according to Space Fax Daily.  The
payload will be seven microsatellites currently under
construction by Defense Systems, Inc.  It will be for the Defense
Advanced Research Projects Agency.






---------------------------------------------------------------
Here's the broadcast schedule for Public Affairs events on NASA
Select TV.  All times are Eastern.


Tuesday, June 5........

       12:00-2:00 P.M.        NASA Video Productions.
                                Birth and death of a star.
                                Supernova 2.
                                Life and the solar system.
                                Robotics in the Space Station.
                                Computer animation movies on
                                  the Earth and Mars.
                                Neptune encounter highlights.


Wednesday, June 6.......

        2:00 P.M.             Voyager I Solar System "Family
                              Portrait" news conference.


Thursday, June 7........

       11:30 A.M.             NASA Update will be transmitted.


-----------------------------------------------------------------
All events and times are subject to change without notice.  These
reports are filed daily, Monday through Friday, at 12:00 P.M.
EDT.  This is a service of the Internal Communications Branch,
NASA HQ.  Contact: JSTANHOPE 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.
-----------------------------------------------------------------

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

Date: 5 Jun 90 16:28:45 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Payload Status for 06/05/90 (Forwarded)


    Daily Status/KSC Payload Management and Operations 06-05-90.


    - STS-35 ASTRO-1/BBXRT (at Pad-A) -

    Launch countdown and scrub/turnaround support continue
    today.


    -STS-40 SLS-1 (at O&C) -

    Mechanical and fluid preps for CITE testing along with MVAK
    training continues.


    - STS-41 Ulysses (at ESA 60) -

    The RTG walkthrough at Pad-B will continue today.


    - STS-42 IML-1 (at O&C) -

    Rack, floor, and module staging along with water servicer
    validations are continuing.


    - STS-45 Atlas-1 (at O&C) -

    Orthogrid installation continues.


    - STS-46 TSS-1 (at O&C) -

    Coldplate lifter beams were modified third shift today.


    - STS-47 Spacelab-J (at O&C) -

    Rack 4 staging will be performed today.


    - STS- 55 SL-D2 (at O&C) -

    Rack 12 staging continues.


    - STS-LON-3 HST M&R (at O&C) -

    ORUC interface testing will be active today along with MLI
    installation.

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

Date:        Tue, 05 Jun 90 08:37:41 CDT
From: CC731CC <[e-mail]>
To: <[e-mail]>
Subject: SPACE Digest V11 #489

PLEASE! Remove me from this list.

Sorry for the interruption.
    -Brian

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

End of SPACE Digest V11 #494
*******************