Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V12_0/V12_009.ZIP/V12_009

Internet Message Format | 1991-07-08 | 16KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/oaY41d:00VcJE77E5r>;
          Tue,  3 Jul 1990 02:51:22 -0400 (EDT)
Message-ID: <[e-mail]>
Precedence: junk
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Tue,  3 Jul 1990 02:50:50 -0400 (EDT)
Subject: SPACE Digest V12 #9

SPACE Digest                                       Volume 12 : Issue 9

Today's Topics:
            Re: HST focus problem
         Applications of Speech Recognition in space
         NASA Headline News for 07/02/90 (Forwarded)
         Re: Bringing the HST down -- even possible?
          Re: Reflections on Hubble and NASA
        Re: The HST was risky from square one
         Re: Hubble Space Telescope Update - 06/28/90
               Hubble mirrors.
        Re: The HST was risky from square one
           Re: NSS protests Chinese launch pricing
           Re: NSS protests Chinese launch pricing
        Re: Testing of Hubble Space Telescope

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: 2 Jul 90 12:35:46 GMT
From: mcsun!ukc!edcastle![e-mail]  (H Neves)
Subject: Re: HST focus problem

Is it not possible to use the real curvature data (presumably avaliable
from the manufacturer's test) to help solving it? Instead of compensating
the image based on a feedback system (prone to S/N limitations) this
would make use of focus variation data together with curvature data.
Sorry if it sounds absurd...

H.Neves
[e-mail]
Edinburgh, Scotland

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

Date: 2 Jul 90 17:32:04 GMT
From: mcsun!ukc!edcastle![e-mail]  (J Crowe)
Subject: Applications of Speech Recognition in space

If anyone has any information/contacts/anything_at_all on the topic of
applications of speech recoginition systems in space, I'd be really
grateful to receive stuff.  I have a couple of articles from back issues
of Speech Technology magazine, but that's all, so *anything* would be
much appreciated!

Thanks,
Jeremy.

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

Date: 2 Jul 90 18:10:35 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 07/02/90 (Forwarded)

-----------------------------------------------------------------
Monday, July 2, 1990                 Audio Service:  202/755-1788
-----------------------------------------------------------------
This is NASA Headline News for Monday, July 2.........

Preparations at the Kennedy Space Center pad 39-A for the
upcoming STS-38 launch scheduled for mid-July included a special
tanking test held on the orbiter Atlantis last Friday.  The test
verified a leak in the orbiter-to-external tank 17-inch umbilical
area.  Leak detectors exterior to the umbilical revealed hydrogen
shortly after the fueling process went from a slow fill to a fast
fill mode.

Engineers report it appears the leak is in a cavity between the
orbiter and external tank umbilical plates.  Although the leak's
precise location has not yet been identified, tests indicate the
17-inch line between the orbiter and the external tank used to
feed the hydrogen to the orbiter's three main engines is
contributing to the leak.  Data from the tests will continue to
be reviewed.

At this time, the external tank has been drained of the liquid
hydrogen used in the test.  Thorough inspections are being
performed in the orbiter's aft compartment.  Until the cause of
the leak has been determined, further processing of the STS-38
vehicle has been suspended.

Although similar to the leak that caused the postponement of the
STS-35/Astro-1 mission, the leak appears to be smaller than the
one detected during the tanking exercise on the STS-35 vehicle
prior to its rollback to the Vehicle Assembly Building and
demating.

Meanwhile, at the KSC Orbiter Processing Facility, the 17-inch
disconnect has been removed from the Space Shuttle Columbia.  It
is being prepared for shipment to the vendor for further testing
and analysis.  The disconnect from the Shuttle Endeavour arrived
at KSC last Thursday night and is scheduled to be installed in
the orbiter Columbia this week.

Also at KSC, preparations are underway to install the three main
engines on the orbiter Discovery this week.  Orbiter structural
inspections and routine testing of all the orbiter's systems will
continue as planned.  The Discovery is being prepared for the
STS-41/Ulysses flight scheduled for launch in October.

A progress update on the Space Shuttle activity will be discussed
on NASA Select TV.  A news briefing will be held with Associate
Administrator for Space Flight Dr. William Lenoir and Space
Shuttle Director Robert Crippen on Tuesday, July 3 at 4:00 P.M.
EDT.

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

Monday, July 2.........

        10:30 A.M.     Media briefing with NASA Administrator
                       Richard H. Truly, Associate Administrator
                       for Space Science And Applications Dr.
                       Lennard Fisk and Associate Administrator
                       for Space Flight Dr. William Lenoir at
                       NASA Headquarters.


Tuesday, July 3........

         4:00 P.M.     Media briefing with Associate
                       Administrator for Space Flight
                       Dr. William Lenoir.


Thursday, July 5.......

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




---------------------------------------------------------------
All events and times are subject to change without notice.  These
reports be 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 R2R, Transponder 13, C-Band, 72 Degrees
West Longitude, Audio 6.8, Frequency 3960 MHz.
---------------------------------------------------------------

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

Date: 2 Jul 90 20:19:20 GMT
From: agate!sag4.ssl.berkeley.edu![e-mail]  (David Ray)
Subject: Re: Bringing the HST down -- even possible?

Even if the Shuttle flights could be reserved, and even if the Hubble
could fit into the cargo bay, there is some question as to whether it
would survive the trip back to Earth. The highest g-forces during a
Shuttle flight are during re-entry, not lift-off, and many space
payloads are designed to survive deployment in space but not re-entry.
The most feasable plan is to service it in space.

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

Date: 2 Jul 90 11:42:18 GMT
From: hsi!mlfarm![e-mail]  (Ronald Florence)
Subject: Re: Reflections on Hubble and NASA

[e-mail] writes:

 >   Lets draw a lesson from Hubble himself.  He first studied law and
 > passed the bar.  He then enlisted and became an officer.  Later
 > he turned Yerkes,  'a moribund institution', into a major research center
 > and made many famous discoveries.  Pretty good for such a humble
 > start in the wrong direction.

The comparison between Hubble and NASA is valid, though in a slightly
different way.  Hubble's autobiography shouldn't be trusted any more
than his British accent, which was pure affectation.  Yerkes was
hardly a "moribund" institution before Hubble's arrival.  Under Hales
it was probably the premier institution for astronomical research in
the United States.  Hubble dismissed the work of Shapley and his other
predecessors at Mount Wilson as "of no significance", which is
remarkably like the NASA press releases which described the Hubble
Space Telescope as the most important event in astronomy since
Galileo.
--

Ronald Florence            {yale,uunet}!hsi!mlfarm!ron

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

Date: 2 Jul 90 13:46:52 GMT
From: uc!shamash!timbuk!sequoia![e-mail]  (Greg Titus)
Subject: Re: The HST was risky from square one

In article <[e-mail]> [e-mail] (John A. Weeks III) writes:
>Discover Magazine, July 1989, Page 68 "The Big Glass".  Excellent article
>on the construction of the primary mirror.  Drama, suspense, and technical
>details.

See also Sky & Telescope, July 1989, Page 31: "Building the Hubble
Space Telescope", by C. Robert O'Dell.

greg
--------------------------------------------------------------
Greg Titus ([e-mail])             Compiler Group (Ada)
Cray Research, Inc.                               Santa Fe, NM
Opinions expressed herein (such as they are) are purely my own.
--
--------------------------------------------------------------
Greg Titus ([e-mail])             Compiler Group (Ada)
Cray Research, Inc.                               Santa Fe, NM
Opinions expressed herein (such as they are) are purely my own.

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

Date: 2 Jul 90 16:22:42 GMT
From: idunno!idacrd![e-mail]  (Robert McGwier)
Subject: Re: Hubble Space Telescope Update - 06/28/90

From article <[e-mail]>, by [e-mail] (George William Herbert):
> In article <[e-mail]> [e-mail] (Robert McGwier) writes:
>>
>>I don't believe this for a second when I KNOW of testing facilities that
>>EXISTED at the time and from yesterday's papers they were offered and
>
> Nice idea, but it's not quite that simple.  You have intrinsic problems
> testing a flexible mirror in a gravity well when it's supposed to be
>

Where you are wrong, is to assume that the test facilities I talked about
did not assume thin mirrors.  Just in case you need to be told, this is
_NOT_ this countries first telescope in orbit.  The earlier ones just didn't
point up.  I agree that the test facilities I mentioned could NOT test these
mirrors to the limits of surface accuracy they could achieve in space, given
that the mirrors were ground properly here.  They _COULD_ have detected
easily this gross error in the combined system.  I do believe this to be
a case of not invented here and almost criminal mismanagement.  I still
remain livid.

Bob

--
____________________________________________________________________________
    My opinions are my own no matter    |    Robert W. McGwier, N4HY
    who I work for! ;-)            |    CCR, AMSAT, etc.
----------------------------------------------------------------------------

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

Date: 2 Jul 90 11:36:45 GMT
From: attcan!utgpu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!ists!nereid![e-mail]  (Harold Peter White)
Subject: Hubble mirrors.


Its amazing how incredible hindsight desides what is cost effect (or even
possible) to check out. And yes, I was (and still am) working with a group on
Hubble proposals. It hasn't become a garbage can yet by a long shot.

But anyway, my question is for all those who have built (or attempted to build)
there own telescope. If you know that you have a problem with a primary mirror,
is it not impossible to design a new secondary to work with it? And is it just
possible to replace the secondary on the Hubble when the repair group goes up?
This seems like a possiblity that no-one has suggested yet, but I can see why it
shouldn't be considered.

H. Peter White
[e-mail]
[e-mail]

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

Date: 3 Jul 90 03:37:33 GMT
From: well![e-mail]  (Charles Hawkins Mingo)
Subject: Re: The HST was risky from square one

In article <[e-mail]> [e-mail] (Doug McDonald) writes:
>Then why didn't they test the components? In a way that would have discovered
>a very serious very  large error?
>. . . pure stupidity and or incompetence.

    From what I read in the New York Times, NASA had three testing
alternatives.  First of all, they could build a special mount and test
the mirrors together; this is the optimal engineering solution, but it
costs several hundred million dollars.  Secondly, they could just test the
mirrors individually, to see if they were manufactured to spec (which they
did); the cheapest solution, which catches the most likely problem: a
manufacturing error.  Thirdly, they could have used equipment used to
test spy satellites; this would have allowed the mirrors to be tested
together, and would only have cost about $10 million, but the military
test would only detect errors 5 times the maximum NASA allowed; while it
_would_ have cought this bug, the most probable manufacturing flaws would
have gone undetected.

    All in all, it's very easy to criticize in hindsight.  The real
question is whether NASA acted reasonably in light of the facts known at
the time.  Apparantly, NASA should have paid more attention to design error
than manufacturing error, but designers often have to simply assume that
the calculations are valid, because there is no easy way to test them
(as here).
--
--
Charlie Mingo                    Usenet: mingo@well!apple.com
2209 Washington Circle #2            CI$:  71340,2152
Washington, DC  20037                AT&T:  202/785-2089

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

Date: 2 Jul 90 21:08:29 GMT
From: usc!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!ofa123![e-mail]  (Mark Perew)
Subject: Re: NSS protests Chinese launch pricing

David -

I think that it is legitimate that NSS make a complaint and ask
for an inquiry.  If the Chinese can *actuallY* launch something
cheaper then we shouldn't complain about it (but HR 2674 would
bar the US payload market from taking advantage of this lower
cost!).  However, if they can't (and I strongly suspect that
they can't) then we have a legitimate beef about them dumping
on the market.


--
uucp:     Mark Perew
Internet: [e-mail]
BBS:      714 544-0934   2400/1200/300

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

Date: 2 Jul 90 17:36:46 GMT
From: usc!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!ofa123![e-mail]  (David Anderman)
Subject: Re: NSS protests Chinese launch pricing

How can NSS complain about Chinese launch pricing if it does not know
Chinese launch costs? Is NSS privy to Chinese internal accounting?


--
uucp:     David Anderman
Internet: [e-mail]
BBS:      714 544-0934   2400/1200/300

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

Date: 3 Jul 90 03:44:12 GMT
From: well![e-mail]  (Charles Hawkins Mingo)
Subject: Re: Testing of Hubble Space Telescope

In article <[e-mail]> [e-mail] (Brad Templeton) writes:
>But I refuse to believe that a test that would have detected real BONEHEAD
>errors like a 1/2 wave curvature error would have been expensive.

    Ah, but thet weren't looking for _bonehead_ errors, they were looking
for subtle, microscopic errors.

    You'd be surprised how bany bonehead errors are made by people who
only look for minor imperfections.  At the Diablo Canyon power station, they
installed the two reactors backwards and upside-down.  Pilots often make
180-degree navigational erors (football players, too, on occasion).
--
Charlie Mingo                    Usenet: mingo@well!apple.com
2209 Washington Circle #2            CI$:  71340,2152
Washington, DC  20037                AT&T:  202/785-2089

--
--
Charlie Mingo                    Usenet: mingo@well!apple.com
2209 Washington Circle #2            CI$:  71340,2152
Washington, DC  20037                AT&T:  202/785-2089

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

End of SPACE Digest V12 #9
*******************