Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v11_5/v11_582.txt

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Subject: SPACE Digest V11 #582

SPACE Digest                                     Volume 11 : Issue 582

Today's Topics:
           Re: VOTE: Lynch Mob for a HST Personal!
                 Hubble GIFs
           Payload Status for 06/27/90 (Forwarded)
            Re: Public Perception Of Space
              Re: Saturn Rockets
               Re: Hubble GIFs
        moon to rocket lower staging problems
           Re: The Scout, Pershing II's and ICBM's
       NASA Prediction Bulletin Format  (for STEPHEN?)
         Re: Hubble Space Telescope Update - 06/27/90

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: 28 Jun 90 20:31:20 GMT
From: uoft02.utoledo.edu![e-mail]
Subject: Re: VOTE: Lynch Mob for a HST Personal!

In article <[e-mail]>, [e-mail] (Doug McDonald) writes:
>
>>Before you get carried away here, note that not all of the HST
>>systems could be tested until it was in a microgravity
>>enviroment.
>
> Testing the optics together on the ground could have been done,
> but........
>
> It would be really impossible to test them definitively, as a unit, as a
> null test, the best way. There is the problem of deformation due to
> gravity. They could have - and should have - at least tried testing the
> system as a whole by taking the two sets of optics (they did have two sets,
> didn't they?)

No I do not beleive they did due to expenses.  I know they only had
one primary and one secondary mirror.

>and pointing them at one another. But this still would
> not account for the deformation due to gravity. There they could have tried
> testing the optics while immersed in a liquid with a specific gravity
> matching the mirror.

Its not that simple.  You can't just immerse the mirrors.  The coatings
used frequently react very badly to other elements.  Not only would
you probably get useless results you very well could end up harming the
mirror.  This is why backset theorizing is so bad.  Lets get all the
facts before we say 'they could have, should have'.

>But this would not be a null test.
>
> Considering that they were touting these as the "most perfect mirrors
> ever made" I had assumed that they had tested them every which way.
>

I think they did.

So you even say they could not test definitively so whay are you complaining
over the way they tested?  Where you there, do you know what they should
have done but didn't?

> They certainly had the time to test them.
>
> Doug MCDonald   (what took you so long?)

Robert Dempsey
Ritter Observatory

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

Subject: Hubble GIFs
From: [e-mail] (THE GAR)
Date:    Wed, 27 Jun 90 08:32:03 GMT

I have received two files that claim to be the First and Second pictures
from the Hubble.  I don't have a Listserv and I am not at an FTPable
site, so here's what I would like to do:    If you have a Listserv, or
FTP site that would like to post these    images, send me a note
(GLWARNESAMFORD), and I will send you the    files.  If you just want a
copy for yourself, hold on and hopefully    these will be FTPable or
LISTSERV GETable very soon.       The resolution on these GIFs is 720 X
480, but they are still pictures from a VERY FAR PLACE, so don't expect
perfect images.  The first file compares the image to the identical
image from a ground based telescope.  The second is just Hubble.
 /====================================================================\
!  Later                                                               !
!  THE GAR             <----- "Gar" rhymes with Share, and has nothing !
!  (GLWARNER@SAMFORD)            at all to do with long nosed fish!    !
 \_____________________________________________________________________/

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

Date: 27 Jun 90 16:49:21 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Payload Status for 06/27/90 (Forwarded)


            Daily Status/KSC Payload Management and Operations 06-27-90.


            - STS-35 ASTRO-1/BBXRT (at OPF) -

            Experiment monitoring continues.


            - STS-37 GRO (at PHSF) -

            Functional testing continues.


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

            CITE testing will be active today.


            - STS-41 Ulysses (at Hanger AO) -

            Ulysses functional testing continues.  At the VPF, PCP/CIU
            testing will be performed today.


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

            Rack, floor, and module staging is continuing.


            - Atlas-1 (at O&C) -

            RAU mating plates and code plugs will be installed today.
            Orthogrid installation is continuing.


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

            Closeout inspections continue.


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

            Rack 11 and 7 staging continues on second shift.

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

Date: 27 Jun 90 16:53:42 GMT
From: usc!elroy.jpl.nasa.gov!jpl-devvax![e-mail]  (Steve Jenkins)
Subject: Re: Public Perception Of Space

In article <kaW=[e-mail]> [e-mail] (Jon C. Slenk) writes:
>* Overall, the situation is, as I see it, this:
>    The government shouldn't do anything other than protect rights.
>    The concept of a free market should do everything else.
>
>[....]
>
>Thus, the problem! Hope this makes my position somewhat clearer
>(in that I think people have the wrong ideas regarding the purpose of a
>government).

The government of the United States was ostensibly founded upon the
principle that the people explicitly invest their government with the
powers enumerated in the Constitution, which serves as the instrument
of their consent.  It's no accident that the Constitution begins with
the phrase "We, the people".

The government should do what the people wish it to do, subject to the
constraints of the Constitution.  How exactly do you conclude that this
is a "wrong idea"?

--
Steve Jenkins N6UNI            [e-mail]
Caltech/Jet Propulsion Laboratory    [phone]

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

Date: 27 Jun 90 08:32:52 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Re: Saturn Rockets

From article <[e-mail]>, by [e-mail] (Henry Spencer):
> A.  (Henry Spencer)  The Saturn I was the original Saturn first stage with
>     a small liquid-hydrogen upper stage.  Apart from some test
>     flights, it launched the Pegasus micrometeorite-measurement
>     satellites.  There were plans to use it for early Apollo flights.
>     Basically, the IB took over its major missions.  In hindsight,
>     the I was a dead end that probably shouldn't have been pursued.
It was designed when there were no operational US LH2/LOX boosters, well
before the RL10 engines first flew, on a Centaur, and when multiple
flight tests were the norm. "All up" testing had to be sold against the
misgivings of many at MSFC. Do you really think they could have started
with the Saturn IB, and does anyone else share your opinion?

Nick (opinions coloured by "Apollo" by Murray & Cox, which makes it
clear how tricky the Saturn V developement was, and how surprised people
were when Apollo 4 worked first time).
--
Dr. Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: [e-mail]   BITNET: [e-mail]

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

Date: 27 Jun 90 22:02:03 GMT
From: mcsun!hp4nl!swi.psy.uva.nl![e-mail]  (Ferry van het Groenewoud)
Subject: Re: Hubble GIFs

[e-mail] (THE GAR) writes:

>I have received two files that claim to be the First and Second pictures
>from the Hubble.  I don't have a Listserv and I am not at an FTPable
>site, so here's what I would like to do:    If you have a Listserv, or

Wouldn't it be better to have sci.space.pictures and mail the pictures over
the net (since there obviously are many people that would like to have the
pictures).
Ferry.

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

Date: 27 Jun 90 19:28:27 GMT
From: att!watmath!maytag!watdragon!watfun![e-mail]  (Fred Walter)
Subject: moon to rocket lower staging problems

With all this discussion on model/amateur rockets to the moon (but no
actual figures being posted, such as the weights of the rocket engines) one
wonders whether or not it'd actually work.

Some comments :

        1) If you are doing staging, the materials holding the stages
           together will add weight that must be taken into consideration.

        2) How will you ensure that the stages separate properly ?
           Without damaging the upper stages ? While properly igniting the stage
           above it ?

        3) Where will the lower stages end up falling ? On houses/people ?
           Or will you be launching from over water ? Will the discarded stages
           have a parachut on them to slow them down on their return, to
           try and ensure they don't kill anything ? How will this be
           handled ?

        4) If you try and put multiple rocket motors together side-by-side
           in a stage, how do you compensate for the fact that their
           thrusts won't be exactly the same ? How do you ensure they
           all ignite at the same time ? Failure to handle either of these
           will result in an off course rocket.

Since you'll need multiple stages in order to get to the moon, these
issues will have to be dealt with. Can they be dealt with in a cost
effective manner ?

    fred

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

Date: 27 Jun 90 16:44:19 GMT
From: mojo![e-mail]  (Doug Mohney)
Subject: Re: The Scout, Pershing II's and ICBM's

In article <[e-mail]>, [e-mail] (Mark SOKOLOWSKI) writes:

>At the same time a major disarmement effort can make ICBM's
>affordable for free.

They wouldn't be "free." You would have to buy them as surplus(?). One or two
of the Titan(s) retired in the early '80s might have been refuburished to
launch a payload, but I'm not real sure about this.

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

Date: 28 Jun 90 17:54:48 GMT
From: usc!cs.utexas.edu!ut-emx![e-mail]  (Frank Abernathy)
Subject: NASA Prediction Bulletin Format  (for STEPHEN?)

Folks, bear with me...  I tried to send a reply to Stephen,
I believe was his name, it bounced so I'm posting hoping he'll
see this..
==========================cut=================================

From: [e-mail] (TS Kelso)
Subject: NASA Prediction Bulletins

==============================================================================

Data for each satellite consists of three lines in the following format:

AAAAAAAAAAA
1 NNNNNU NNNNNAAA NNNNN.NNNNNNNN +.NNNNNNNN +NNNNN-N +NNNNN-N N NNNNN
2 NNNNN NNN.NNNN NNN.NNNN NNNNNNN NNN.NNNN NNN.NNNN NN.NNNNNNNNNNNNNN

Line 1 is a eleven-character name.

Lines 2 and 3 are the standard Two-Line Orbital Element Set Format identical
to that used by NASA and NORAD.  The format description is:

Line 2
Column     Description
 01-01     Line Number of Element Data
 03-07     Satellite Number
 10-11     International Designator (Last two digits of launch year)
 12-14     International Designator (Launch number of the year)
 15-17     International Designator (Piece of launch)
 19-20     Epoch Year (Last two digits of year)
 21-32     Epoch (Julian Day and fractional portion of the day)
 34-43     First Time Derivative of the Mean Motion
        or Ballistic Coefficient (Depending on ephemeris type)
 45-52     Second Time Derivative of Mean Motion (decimal point assumed;
           blank if N/A)
 54-61     BSTAR drag term if GP4 general perturbation theory was used.
           Otherwise, radiation pressure coefficient.  (Decimal point assumed)
 63-63     Ephemeris type
 65-68     Element number
 69-69     Check Sum (Modulo 10)
           (Letters, blanks, periods = 0; minus sign = 1)

Line 3
Column     Description
 01-01     Line Number of Element Data
 03-07     Satellite Number
 09-16     Inclination [Degrees]
 18-25     Right Ascension of the Ascending Node [Degrees]
 27-33     Eccentricity (decimal point assumed)
 35-42     Argument of Perigee [Degrees]
 44-51     Mean Anomaly [Degrees]
 53-63     Mean Motion [Revs per day]
 64-68     Revolution number at epoch [Revs]
 69-69     Check Sum (Modulo 10)

All other columns are blank or fixed.

Note that the International Designator fields are usually blank, as issued in
the NASA Prediction Bulletins.
====================================cut=================================

Hope this helps the original requestor...
frank
(Credit for the service of posting the NASA preditions goes, of course, to
Dr. Kelso...)

--
Frank Abernathy, University of Texas at Austin, [e-mail]
Work: (512)-471-3216      Home: (512)-244-0625 (ans. mach always on...)

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

Date: 28 Jun 90 19:18:26 GMT
From: skipper![e-mail]  (Al Bowers)
Subject: Re: Hubble Space Telescope Update - 06/27/90


In article    From: [e-mail] (Ron Baalke)


>The optical system is a variation of a Cassegrain
>design, called Ritchey-Chretien, which uses a folded design to enable
>a long focal length of 189 feet to be packaged into a small telescope
>length of 21 feet.  Both mirrors are hyperboloidal in shape, meaning they
>have a slightly deeper curvature than a parabolic mirror.  This shape was
>to correct all coma and spherical aberations everywhere in the field of
>view.

Now, I'm certainly no optical expert, but isn't a Ritchey-Chretien's
secondary an elliptical mirror?  I do know it provides a flat field,
no coma, no spherical aberration, no chromatic aberration (being a
reflector telescope).  It does have off axis astigmatism though.

I was just curious.

Another opinion...

--
Albion H. Bowers  [e-mail]  ames!elxsi.dfrf.nasa.gov!bowers

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

End of SPACE Digest V11 #582
*******************