Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_6/V12_642.TXT

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Subject: SPACE Digest V12 #642

SPACE Digest                                     Volume 12 : Issue 642

Today's Topics:
        Re: Correction to my list of Firsts...
         NASA Headline News for 12/05/90 (Forwarded)
             ASTRO status at 3/11:48 MET
      Astro-1 Status for 12/05/90 [1239 CST] (Forwarded)
             atmospheric pressure on Mars
               ASTRO status at 3/20:54
           Martian atmosphere/Total Recall
             Re: * SpaceNews 03-Dec-90 *

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription notices,
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----------------------------------------------------------------------

Date: 5 Dec 90 00:59:43 GMT
From: usc!cs.utexas.edu!sun-barr!newstop!exodus!concertina.Eng.Sun.COM![e-mail]  (Steve Hix)
Subject: Re: Correction to my list of Firsts...

In article <[e-mail]>, [e-mail] (Steve "il-Manhous" Norton) writes:
> BTW, If I may point out something to all of the most kind people who have
> responded:  The Hubble does not do what it was designed to do.  It fails
> to do so because it has flaws.  Consequently, I called it broken.

Ever built an airplane?  As in one that you can fly in?

If you've done your work right (and the designer has done all his/her/its
homework), then it's kick the tires and light the fires.

Normally, however, (and especially if this is a new design) the first flight
shows any number of problems.  Some less minor than others.

It might take quite a while to iron out the bugs and wrinkles and rough
spots, but eventually you either get it all working right, or give up in
disgust and trash it.

The HST is a one-off, first-time, no-prototype item.  And it's showing
bugs, wrinkles,...  A lot of the problems aren't even up in space right
now, there were errors in procedures, etc. that were done down here.  (And
a bunch of 'em got re-elected, too.)

Frankly, I'm a bit suprised that it workds as well as it does.  The
functional problems are irritating, but they can be fixed.

What are the chances that the ground-based problems are going to be fixed?
The people who worked on this are going to be working on other things in
the future.  Want to bet on how many lessons learned on this are going to
be applied in future efforts, as opposed to how many errors will be repeated
elsewhere?

> I'm entirely aware that the Hubble might be brought up to speed sometime
> in 1993, but that does not make it any less flawed.

You probably wouldn't like working in some consumer-engineering field.  There
are few new products that don't come out with some problem or other than has
to be fixed after the fact.  (Not even if you're based in Stuttgart or Kobe.)

A big budget is no guarantee of perfection...it's just a big budget.  And this
isn't necessarily all due to stupidity or laziness, just human imperfection.

Sorry about that.

--
------------
  The only drawback with morning is that it comes
    at such an inconvenient time of day.
------------

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

Date: 5 Dec 90 18:00:30 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 12/05/90 (Forwarded)


             Headline News
Internal Communications Branch (P-2) NASA Headquarters

  Wednesday, December 5, 1990    Audio Service: 202 / 755-1788

This is NASA Headline News for Wednesday, December 5, 1990

"We have an observatory that's really coming alive now. ...  We're
starting to make science!" exclaimed Mission Scientist Ted Gull,
reaffirming the improving status of the mission, as Astro-1moved
farther from a checkout mode to its science mode.  The Shuttle-borne
observatory has made complete science observations and the Instrument
Pointing System has greatly improved in its operation.  Observations of
significant targets have come with increasing regularity since early
yesterday.

Marked improvements in Astro-1's ability to execute automatic stellar
acquisitions were the result of ground efforts in feeding the star
tracker system successively refined calibrations.  Pointing stability
still remained below specifications, and because control of Spacelab,
the IPS and the experiments is still done on a single computer
terminal, acquisitions require more time than expected.  Both
conditions are expected to improve.

Yesterday evening, the Broad Band X-ray Telescope alignment, with its
Two-Axis Pointing System, was completed, clearing the way for the team
to press on with their science observations.  During this period, the
X-ray telescope made observations of the Crab Nebula and the binary
star system Cygnus X-3.

Observations made by the Ultraviolet telescopes yesterday and last
night included the globular cluster M92, a cluster of some 100,000
stars 25 light- years from Earth containing many very hot, old,
ultraviolet producing stars.  Also observed was the star Theta Muscae,
a Wolf-Rayet star, which exhibits a very strong stellar wind, and the
supernova remant Cygnus Loop, which exploded some 50,000 years ago.
The M81 spiral galaxy was observed, as well as an elliptical galaxy,
M87, a strong X-ray source.  Hopkins Ultraviolet Telescope scientist
Dr. Randy Kimble described a "delightful spectrum" obtained from an
Earth-sized white-dwarf star, only weakly detected prior to Astro-1.

  * * * * * * * * * * * * * * * * * * * * * * * * * *

Over 34 million miles from Earth, and traveling 79,500 mph relative to
the sun, the Ulysses solar probe is gaining stability from the wobble
in its rotation.  The wobble has decreased steadily this week, as the
spacecraft's axial boom moves further into the shade of the body of the
probe, and as its distance from the sun increases.  The wobble has
decreased from six degrees side-to-side motion, to about three
degrees.  Controllers have adopted a wait-and-see stance before taking
any immediate action to attempt to reduce the wobble further.


Here's the broadcast schedule for Public Affairs events on NASA Select
TV.  All times are Eastern.  **indicates a live program.

Wednesday, 12/5/90     Mission coverage of the STS-35/Astro-1 flight
             will continue live throughout the week ...

       1:15 pm          Magellan Status Report from JPL
       2:46 pm          Science TV from Astro-1
       3:30 pm          "Today in Space with Dr.  Frank Six from MFSC
       5:00 pm          Change of shift flight director briefing from JSC
       6:00 pm          Mission Manager briefing from MSFC
       7:15 pm          Science TV from Astro-1
       8:57 pm          Science TV from Astro-1
      10:19 pm          Blue/Red crew handover
      11:06 pm          Science TV from Astro-1

Thursday, 12/6/90
      12:12 am          Flight deck activities from Columbia
    1:00 am         Change of shift flight director briefing from JSC
    3:14 am         Science TV from Astro-1
    7:51 am         Science TV from Astro-1
    9:00 am         Change of shift flight directors briefing from JSC
       10:30 am         Mission science briefing from MSFC
       12:24 pm         Flight deck activities from Columbia
     1:47 pm        Science TV from Astro-1
     3:30 pm        "Today in Space" with Dr. Frank Six from MFSC
     4:35 pm        Science TV from Astro-1
     5:00 pm        Change of shift flight directors briefing from JSC
     6:00 pm        Mission manager briefing from MSFC

All events and times may change without notice.  This report is filed
daily, Monday through Friday, at 12:00 pm, EST.  It is a service of
Internal Communications Branch at NASA Headquarters.  Contact:
CREDMOND 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 Dec 90 18:38:57 GMT
From: uvaarpa!murdoch![e-mail]  (Greg Hennessy)
Subject: ASTRO status at 3/11:48 MET

The situation on ASTRO continues to improve, but is by no means as
good as possible. BBXRT is observing, and getting almost all of its
data, although there was a temporary glitch of the Two Axis Pointing
System (TAPS). HUT works well, but has still not aquired any targets.
It has observed 10 objects that WUPPE aquired when WUPPE was primary,
or by manuan acquisition, and gotten VERY nice data. WUPPE has
observed 10 objects, and has one exciting result already, even before
the instrumental polarization is fully finished. There is a well known
dip in UV spectra around 2300 angstroms, which is attributed to
graphite, probably in dust grains. The question is wheter or not the
light is scattered off the grains, or absorbed by the grains. This all
was pointed out 25 years ago by Ted Stecher, the PI of the UIT
telescope. If the light was being absorbed, the polarization would not
be changed, but if the light was scattered, there would be a large
polarization induced into the starlight. The WUPPE team found that the
polarization did NOT change across the line, meaning that the light is
being absorbed not scattered. The UIT telescope made five long
exposures, and 3 short ones. There long observations included the
Perseus cluster, NGC2992, and the Crab Nebula, and M87.

The science teams are still not happy with  with the tracking. When
the star trackers acquire the stars, the stability is very nice, but
the trackers  often do not work. Another patch was uplinked last night
and another test will be this shift.

On shift four there was 0 percent of science being done, on shift five
there was 17, and on shift six there was 35 percent. However that 35
percent counted the time lost for a test as the star trackers as zero
time achieving science, but took in the time. If you only consider the
times that the teams attempted to observe, then the teams achieved 44
percent. The mission is being replanned to take longer exposures, so
better data of fewer objects will be done.

--
-Greg Hennessy, University of Virginia
 USPS Mail:     Astronomy Department, Charlottesville, VA 22903-2475 USA
 Internet:      [e-mail]
 UUCP:        ...!uunet!virginia!gsh7w

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

Date: 6 Dec 90 03:40:45 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Astro-1 Status for 12/05/90 [1239 CST] (Forwarded)


      Astro 1 Mission Report #21
      12:39 p.m. CST, December 5, 1990
      3/11:49 MET
      Spacelab Mission Operations Control
      Marshall Space Flight Center


      Hopkins Ultraviolet Telescope Deputy Project Scientist Randy Kimble
      has good reason to be excited about spectra from a white dwarf star
      tagged G191B2B which the telescope recorded last night.

      "I tried to make a measurement of this star with a sounding rocket
      in 1982 for my Ph.D thesis, but it didn't quite work," Kimble
      recalled during a press science briefing this morning.  "Now I am
      delighted eight years later I could have this spectrum in my hand!"
      Kimble said that his desire to study the star was one of the reasons
      he joined Principal Investigator Arthur Davidsen's Hopkins telescope
      team.

      The scientist reported that the Astro crew, using a contingency
      target acquisition procedure, was able to lock onto the star quickly
      and get two good spectra with a total of 25 minutes observing time.
      (The typical telescope observation launched by a sounding rocket
      might provide 5 minutes of data.)  Emissions from the white dwarf
      were recorded both in the far ultraviolet and the extreme
      ultraviolet, at one time called the "unobservable ultraviolet,"
      Kimble said.

      Also at the briefing, Ultraviolet Imaging Telescope Co-Investigator
      Morton Roberts explained some of the rationale for studying stars.
      "Star formation is of interest because we want to know how we got
      here," Roberts stated.  "After all, the sun is a very important
      star.  If we can understand the general process of star formation,
      we can better understand the formation of the solar system."

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

Date: 6 Dec 90 02:32:38 GMT
From: [e-mail]  (Bill Seward)
Subject: atmospheric pressure on Mars

Here is a question that occured to me for a really silly reason:

In the movie "Total Recall" [no flames on my taste in films, please :-) ],
several people who were exposed to the Martian atmosphere without the
benefit of a pressure suit died from what I can best term semi-explosive
decompression.  That is, they slowly blew up like balloons and popped.

I remember reading, way back somewhere, that a human could survive at
the Martian equator during the summer with only a respirator.  Of course,
this was pre-Viking.

So the question is, what is the atmospheric pressure of Mars at the surface
and could suck a thing happen?  Or was Hollywood just wanting to add a
little gore for the masses?

------------------------------------------------------------------------------
| Bill Seward -- Analyst, Programmer, System Manager, User Training,         |
|                Operations and whatever else needs doing.                   |
|       Cutaneous Pharmacology & Toxicology Center, NC State University      |
| [e-mail]                            [e-mail] |
------------------------------------------------------------------------------

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

Date: 6 Dec 90 03:44:18 GMT
From: uvaarpa!murdoch![e-mail]  (Greg Hennessy)
Subject: ASTRO status at 3/20:54


The observational efficiency of the ASTO observatory continues to
increase, but not as quickly as hoped. The star trackers work
perfectly whenever tested, but still have not worked on a real object.
All science done so far ahas been by the astronauts hand guiding the
telescopes, which results in much less stable images than the nominal
star trackers. The star trackers can be made to work in a certain
fashion, a complicated procedure, but this procedure takes so much
time that it often eats up most of the observing time. The last tests
on teh star tracker show that the three tubes that compose the star
trackers are misaligned by 0.9 degrees. They are supposed to be
coplanar.

During the eigth shift, two problems occured that lost observing time.
One was the crew exercising on the treadmill diring an observation
of P Car. The premission understanding was that the crew would only
excercise during handovers (times when so science was being done) but
this was apparently not written down anywhere. The crew will now only
excercise when the shuttle is in an SAA, a region of higher radiation
where the instruments do not work. Also during the mission the
verniers (small rockets which keep the shuttle pointed in the proper
position). Since this meant that the shuttle had to manuver using the
large rockets, the shuttle doors were closed to prevent contamination
from the fuel, which contains hydrazine. Three observations were
missed, unfortunately the high priority targets the Pleiades,
VW-Hydra, and the cluster Abell 2199. (Talk about rotten luck). These
four targets had zero science done, and specified observation times of
16, 23, 40, and 34 minutes. Sucessful observations were made of the
galaxy 0558-504 with 10 of 15 minutes (67%), M79 (14 of 27, 52%),
SK69-239 (18 of 33, 55%), M79 again (31 of 45, 69%), NGC 1399 (10 of
26, 38%), P-Cyg (33 of 38, 65%), 3C273 (everybody's favority quasar)
41 of 47, 87%, Capella, 12 of 28, 43%, and HD99264, 20 of 29 minutes
for 70 percent. All in total, 39 percent of the scheduled time was
done, compared with 36% for shift 7, 17% for shift 6, and 0% before
that. The next shifts observations will be done with a software patch
to correct for the misalighed star tracker.

--
-Greg Hennessy, University of Virginia
 USPS Mail:     Astronomy Department, Charlottesville, VA 22903-2475 USA
 Internet:      [e-mail]
 UUCP:        ...!uunet!virginia!gsh7w

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

Date: 6 Dec 90 06:19:18 GMT
From: usc!zaphod.mps.ohio-state.edu!think.com!mintaka!bloom-picayune.mit.edu![e-mail]  (Matthew T Velazquez)
Subject: Martian atmosphere/Total Recall


    The Martian atmosphere is something like .005 to .008 bars at the
surface. Earth's sea level atmosphere is about 1 bar.

    The squirming and gagging you saw in Total Recall would have looked
more like this:


    ********    ********    *        *        *******
    *       *      *    *    **        *       *       *
    *    *      *    *     * *        *       *       *
    ********       *    *    *  *        *       *
    *    *      **********    *   *       *       *     ***
    *       *      *    *    *    *      *       *       *
    ********       *    *     *     *******        *******


    Personally, I think it would have been a better effect.

    But that's me.


                -T

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

Date: 4 Dec 90 18:37:21 GMT
From: sdd.hp.com!wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: * SpaceNews 03-Dec-90 *

In article <[e-mail]> [e-mail] (Franklin Antonio) writes:
>So, the basic work was done 371 years ago!  This is one of the humbling things
>about celestial mechanics...

Kepler is not the really humbling example in celestial mechanics.  That
honor goes to Isaac Newton, not much later.  After deducing that gravity
followed an inverse square law, he explored the consequences of that
(including deriving Kepler's Laws) so thoroughly that the greatest
mathematicians of the next two centuries basically just added footnotes
to his work.
--
"The average pointer, statistically,    |Henry Spencer at U of Toronto Zoology
points somewhere in X." -Hugh Redelmeier| [e-mail]   utzoo!henry

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

End of SPACE Digest V12 #642
*******************