Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_5/V11_505.TXT

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Date: Fri,  8 Jun 1990 01:44:51 -0400 (EDT)
Subject: SPACE Digest V11 #505

SPACE Digest                                     Volume 11 : Issue 505

Today's Topics:
         Termination of Lunar/Mars intiative
          Re: DSN Reliability and Resources Question
            Ulysses risks I: Design of RTG
        Re: "CCD imagers in HST" from EE Times
            Re: ROSAT IN ORBIT!!!!
            Re: ROSAT IN ORBIT!!!!
            Jonathan's Space Report, Jun 6
        Re: "CCD imagers in HST" from EE Times

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

Date: 6 Jun 90 22:48:12 GMT
From: ptolemy![e-mail]  (Charles Fineman)
Subject: Termination of Lunar/Mars intiative


The following is from a letter from Charlie Walker, former shuttle astronaut,
and President of the National Space Society:

Congress is ready to terminate the Lunar/Mars (aka Space Exploration)
initiative.

*** ZERO FUNDING ***  [emphasis added by poster]

The decision to cut this program has already been made behind the scenes.
Congress is only waiting to return from the Mermorial Day recess to vote
this important program out of existence.

Termination would be catastrophic.  No program is of more importance to
[the US (both government AND comercial) space program].

Without this program there will be ... *NO* manned activity in space beyond
low earth orbit for the foreseeable future.

This is what YOU need to do, if the Lunar/Mars [aka: Space Exploration]
initiative is to survive.

Telephone or write (preferably telephone):

Senator Barbara Mikulski (D-MD)   and   Congressman Bob Traxler (D-MI)
320 Hart Senate Office Building         2364 Rayburn Building
Washington, DC 20510                    Washington, DC 20515
[phone]                          [phone]

Your call or letter MUST arrive during the week of June 4 to be fully
effective.  The earlier, the better.  Updated information reguarding
timing can be obtained by call the Space Hotline [phone].

[An important side effect of this issue is presidential embarrassment].
If President Bush fails in this effort - an effort he began - an effort
for which he has expressed strong personal support, then other space
initiatives will [fail to get] the attention that they [need].  In fact,
it is unlikely that there will be any new space initiatives [by Bush or
any other presidents] for a long time.

The space program is in jeopardy.

Let your opinion count in this vital vote on America's future.  Call or
write.  America's space program needs your support today!

Thanks you,

Charlie Walker, former shuttle astronaut and pres. NSS

PS:  Your support makes a difference!
According to former NASA administrator, James Fletcher, "Without your letters
and phone calls, there is a [very high probablity] that the space station
program would have been canceled last year."

======

Also, the following senators and congresspersons should be contacted:

Senators:
Frank Lautenberg (D-NJ)
Robert Kerrey (D-MA)
J Bennett Johnson (D-LA)
Wyche Fowler (D-GA)
Patrick Leahy (D-VT)
Don Nickels (R-OK)
Charles Grassley (R-IA)
Phill Gramm (R-TX)

Congresspersons:
Louis Stokes (D-OH)
Alan Mollohan (D-WV)
Jim Chapman (D-TX)
Chester Atkins (D-MA)
Lawrence  Coughlin (R-PA)
Bill Green (R-NY)
Jerry Lewis (R-CA)

All members of Congress ca be contacted by calling 202-224-3121 and
asking for the member in question

Mail to:
Senator (name)               Congressperson (name)
Washington, DC 20510         Washington, DC 20515

Get those calls going in.  Thanks from Space Cause.

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

Date: 6 Jun 90 19:28:28 GMT
From: att!watmath!maytag!watdragon!watyew![e-mail]  (Brian or James)
Subject: Re: DSN Reliability and Resources Question


    This is probably a very stupid question, but are there safeguards
to prevent unauthorised types from successfully sending the HST spurious
commands?
                            JDN

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

Date:     Wed,  6 Jun 90 21:35 CDT
From: William Higgins <[e-mail]>
Subject:  Ulysses risks I: Design of RTG
Original_To:  SPACE

I've summarized what I know about the Ulysses RTG's and the risks posed by its
plutonium dioxide fuel.  Because of its length, I'm breaking my discussion up
into several separate postings.

DESIGN OF ULYSSES RTG

Ulysses is powered by a particular model of radioisotope thermoelectric
generator (RTG) known as a General Purpose Heat Source (GPHS).  Galileo had two
of these, Ulysses has only one.  It is a 55.5-kg device which produces 285
watts of electrical power when its fuel is fresh.

The fuel is plutonium-238 (not 239, the fissionable isotope used in bombs) in
the form of plutonium dioxide, a ceramic.  This isotope decays exclusively by
giving off 5.5 MeV alpha particles, and no other radiation.  Alpha particles
are the easiest kind of radiation to stop.  A thin sheet of paper will stop
most alphas.  The iridium cladding on the plutonium-oxide fuel slugs is more
than enough shielding to prevent radiation from escaping.  It is also malleable
enough to deform under stress without releasing the oxide inside.

The fuel pellets are in cylinders, 2.75 cm in diameter by 2.75 cm long. Each
pellet yields thermal power of 62.5 watts; the 72 pellets loaded into Ulysses
have a total thermal loading of about 4410 watts.  Therefore specific power
for the GPHS is 5.1 watts/kg, and electrical conversion efficiency is 6.8%.

Two cladded pellets go into a cylindrical graphite-epoxy impact shell; this is
wrapped in a carbon-bonded carbon fiber insulator.  Two impact shells go into a
block-shaped graphite-epoxy enclosure called an aeroshell.  The aeroshell,
measuring 9.7 x 9.3 x 5.3 cm, is the primary re-entry protection for the fuel.
The insulators should protect the fuel from the high temperatures of re-entry,
while the impact shells protect it from mechanical impact.

Eighteen aeroshell modules are stacked into the aluminum housing of the GPHS,
which also contains 576 silicon-germanium thermocouples.  In the case of an
accidental reentry, the GPHS is designed to separate into separate modules.
Between $20 million and $30 million have been spent on a testing program to
insure its safety, exposing RTG components to heating, projectile impact,
explosions, immersion in water, and fires.

                      ______meson   Bill Higgins
                   _-~
     ____________-~______neutrino   Fermi National Accelerator Laboratory
   -   -         ~-_
 /       \          ~----- proton   Bitnet: [e-mail]
 |       |
 \       /                          SPAN/Hepnet/Physnet: 43011::HIGGINS
   -   -
     ~                              Internet: [e-mail]

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

Date: 7 Jun 90 03:39:46 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!qucdn![e-mail]  (Arnold G. Gill)
Subject: Re: "CCD imagers in HST" from EE Times

In article <[e-mail]>, [e-mail] (Derek Buzasi) says:
>
>I hate to rain on anyone's parade, but the CCDs used on the HST are not
>even close to being state of the art by modern standards, although they
>may qualify based on 1982 standards. These chips have low quantum
>efficiency (around 32% at best), high noise levels (~15 electrons),
>and relatively low dynamic range by modern standards.
     My question is, why weren't the CCDs exchanged and updated while Hubble
was sitting on the ground in its expensive clean room?  Putting in a better
CCD sounds like a very trivial thing to do, with only minor changes in the
other hardware around it, especially since the signal will so markedly improve.
-------
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
|  Arnold Gill                        |                                     |
|  Queen's University at Kingston     |     If I hadn't wanted it heard,    |
|  BITNET   : gilla@qucdn             |       I wouldn't have said it.      |
|  X-400    : [e-mail]  |                                     |
|  INTERNET : [e-mail]  |                                     |
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Date: 6 Jun 90 13:46:55 GMT
From: mcsun!unido!mpirbn![e-mail]  (Daniel Fischer)
Subject: Re: ROSAT IN ORBIT!!!!

In article <[e-mail]> [e-mail] (Jonathan McDowell) writes (message shortened) :

>The ROSAT x-ray astronomy satellite was launched from LC17B at Cape
>Canaveral at 2148UT today (Jun 1).  Launch was delayed several minutes ...
>... The Harvard-Smithsonian ROSAT team
>rented a satellite dish to watch NASA Select, and celebrated with beer
>and pretzels...

> |  Jonathan McDowell       |  phone : [phone]              |
> |  Center for Astrophysics | uucp: husc6!harvard!cfa200!mcdowell |
> |  60 Garden Street        | bitnet : [e-mail]        |
> |  Cambridge  MA 02138     |  inter : [e-mail]   |
> |  USA                     |   span : cfa::mcdowell     (6699::) |

At the German Space Operations Center (GSOC) at the DLR in Oberpfaffenhofen,
Bavaria, W.Germany, there was a 'lauch party' at this time, with approx. 600
guests, bands playing (folk [i.e.: Blasmusik] and jazz), light shows, lots of
good things to eat, and, of course, NASA Select on a big projection screen.

The final seconds of the CountDown were awesome: people first became very
silent, but from about t-5sec on they started to count louder and louder, and
at ignition the NASA soundtrack was drowned in a tremendous cheer. This
repeated at the first booster separation (NASA's TV coverage was of oustanding
beauty) and again at the second one. It was *big* fun to watch NASA Select from
Europe (not usually available here), and the party was just perfect.

P.S.: During the celebrations I've learned from a key DLR manager involved in
German-Soviet space activities that the Soviet MARS'94 spacecraft will almost
certainly be launched in 1996 not 1994 - they do not want to repeat the PHOBOS
errors. Most likely a very complicated German camera will be on board: with
German unification on the horizon, the Eastern and Western German space
agencies have decided to cooperate in its development.

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

Date: 7 Jun 90 01:04:24 GMT
From: dftsrv!dftnic.gsfc.nasa.gov![e-mail]  (Brian S. Lev)
Subject: Re: ROSAT IN ORBIT!!!!

In article <[e-mail]>, [e-mail] (Jonathan McDowell) writes...
>The ROSAT x-ray astronomy satellite was launched from LC17B at Cape
>Canaveral at 2148UT today (Jun 1).  Launch was delayed several minutes
>when an airliner strayed into the launch area.  Orbit insertion occurred
>at 2159UT and the orbit was circularized at 2226UT.  The spacecraft was
>due to separate from the Delta second stage at 2230, but loss of data at
>the Indian Ocean ground station prevented confirmation of the event at
>the time I am writing this (2250UT).  The Harvard-Smithsonian ROSAT team
>rented a satellite dish to watch NASA Select, and celebrated with beer
>and pretzels...

I LOVE IT!  Seems like the SAO crew and the GSFC crew were on the same wave-
length!  Someone from the group here convinced the management of a nearby
Mexican eatery (one of the big chains) to cut part of their music video system
over to the local cable TV company, which also carries NASA Select TV.  We
enjoyed a happy hour sitting in front of a projection TV, watching that
beautiful bird fly and toasting the fact that we all still had jobs!  It was
especially nice to see the bartended *cut off* the music videos during the
actual launch so that we -- and a number of patrons -- had a clearer view.

>ROSAT observations will begin in a few weeks with the X-ray all sky
>survey. Next year, observatory-type pointed observations will be made.

Yep -- and (as part of the team doing Level 1 & 2 data processing and keeping
the project-dedicated network links "alive") I can't wait... lots of neat stuff
out there to "see" in the X-ray spectrum, and the whole dumb world don't seem
to care...

+----------------------------------------------------------------------------+
|  Brian Lev/STX                           [phone]   (FTS)888-9514     |
|  NASA Goddard Space Flight Center        DECnet: SDCDCL::LEV  (6153::LEV)  |
|  Advanced Data Flow Technology Office    TCP/IP: [e-mail]  |
|  Code 930.4                              BITNET: LEV@DFTBIT                |
|  Greenbelt, MD  20771                    TELENET: [BLEV/GSFCMAIL]          |
|     X.400 Address: (C:USA,ADMD:TELEMAIL,PRMD:GSFC,O:GSFCMAIL,UN:BLEV)      |
+----------------------------------------------------------------------------+
|   "The ability of a network to knit together the members of a sprawling    |
|   community has proved to be the most powerful way of fostering scienti-   |
|   fic advancement yet discovered."  -- Peter Denning                       |
+----------------------------------------------------------------------------+
|     DISCLAIMER: THESE STATEMENTS ARE MY OWN AND *NOT* NASA'S OR STX'S!     |
+----------------------------------------------------------------------------+

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

Date: 6 Jun 90 19:58:47 GMT
From: frooz!cfa250![e-mail]  (Jonathan McDowell)
Subject: Jonathan's Space Report, Jun 6

Jonathan's Space Report

Jun 6 1990 (no.41)
----------------------------------------------------

Launch of STS-38/Atlantis is due for early July. Atlantis will
be transferred from the Orbiter Processing Facility
to the Vehicle Assembly Building this week, where it will
be mated with the ET and SRBs.

Launch of STS-35/Columbia has been rescheduled for August 9.
A fuelling test revealed a leak in the seal between the orbiter
and the External Tank; repairs will require destacking of the
Shuttle in the Vehicle Assembly Building. The delay means that
Spacelab Life Sciences 1 will also slip.

The ROSAT (Rontgensatellit) x-ray astronomy satellite was launched on a
Delta 6920 on Jun 1.  The satellite, which is in a 600 km orbit, is
similar to the Einstein Observatory (1978-81) but with more sensitive
detectors.  ROSAT is a joint project between the German DLR space agency
and NASA, with British collaboration.  The main X-ray telescope focusses
radiation onto the PSPC (Position Sensitive Proportional Counter) which
will make the best survey yet of the X-ray sky.  Another detector, the
HRI (High Resolution Imager) has higher spatial resolution and can be
rotated into the focus of the telescope.  ROSAT also carries a piggyback
British telescope, the Wide Field Camera which will observe the sky in
the extreme ultraviolet.

The Hubble Space Telescope is in its Orbital Verification Phase 1.
All the instruments have been turned on for electronics checks;
acquisition of guide stars has improved greatly. Focussing of the
telescope continues.

Anatoli Solov'yov (Komandir) and Aleksandr Balandin (Bortinzhener)
continue in orbit aboard the Mir complex.  The Soyuz TM-9 transport is
currently at the station.  The Kristall module was launched on May 31,
and is due to dock today at the forward port. It will be transferred
to a side port soon after. Progress-42 undocked from the rear port
on May 27, and Soyuz TM-9 made a 24-min flight from the front port
to the rear port on May 28, leaving the front port open for Kristall.
Solov'yov and Balandin have been in space for 114 days.

The 6th Resurs-F remote sensing satellite was launched on May 29
by Soyuz from Plesetsk.

(c) 1990 Jonathan McDowell

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

Date: 7 Jun 90 14:46:29 GMT
From: frooz!cfa250![e-mail]  (Bill Wyatt)
Subject: Re: "CCD imagers in HST" from EE Times

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

It better be, at 1.5 gigabucks! Actually, NASA PR really blew it by
overstating the expectations this early in the mission. Every
instrument, ground-based or not, has an extensive check-out and
calibration period. It always takes more time that you expect to
optiimize an instrument, sometimes weeks, more likely years.

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

Wrong. Remember, these chips were state-of-the-art 10 years ago.
Each chip is 800x800, and there are mosaics up to 2x2, for a total
of 1600x1600. The 2048x2048 size has only become common in the last
year or two. TI no longer makes CCD chips, btw.

Bill Wyatt, Smithsonian Astrophysical Observatory  (Cambridge, MA, USA)
    UUCP :  {husc6,cmcl2,mit-eddie}!harvard!cfa!wyatt
 Internet:   [e-mail]
     SPAN:   cfa::wyatt                 BITNET: wyatt@cfa
--
Bill Wyatt, Smithsonian Astrophysical Observatory  (Cambridge, MA, USA)
    UUCP :  {husc6,cmcl2,mit-eddie}!harvard!cfa!wyatt
 Internet:   [e-mail]
     SPAN:   cfa::wyatt                 BITNET: wyatt@cfa

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

End of SPACE Digest V11 #505
*******************