Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_7/V13_796.TXT

Internet Message Format | 1991-07-06 | 17KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from hogtown.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/YcRN2HW00WBwQLoE5n>;
          Sat,  6 Jul 91 05:42:43 -0400 (EDT)
Message-ID: <[e-mail]>
Precedence: junk
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Sat,  6 Jul 91 05:42:38 -0400 (EDT)
Subject: SPACE Digest V13 #796

SPACE Digest                                     Volume 13 : Issue 796

Today's Topics:
       Re: NASA Headline News for 06/24/91 (Forwarded)
               Aviation Week on Galileo
         Asteroid grazed atmosphere in 1972?
           Stanford Mars Landing Report Available?
    Research asst. positions w/NASA satellite project, UC Berkeley
             Re: Aurora geometry
     Programmer positions w/NASA satellite project at UC Berkeley

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 26 Jun 91 21:50:30 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!usc!elroy.jpl.nasa.gov!jato!kelvin.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Re: NASA Headline News for 06/24/91 (Forwarded)

In article <[e-mail]>, [e-mail] (John A. Weeks III) writes...
>In <[e-mail]> [e-mail] (Peter E. Yee) kindly posts:
>> Headline News
>
>> [...]  JPL continues its anomaly investigation into the cause and
>> possible fixes for the partial deployment of the spacecraft's high gain
>> antenna.  The data from the Gaspra flyby can be recorded onboard the
>> spacecraft, for later playback at the second Earth encounter in
>> December, 1992.
>
>Does anyone know if the data playback during the second Earth fly-by is going
>to affect the ability to collect data on the second Earth encounter?  The
>first Earth encounter was spectacular (actually the Moon photos were the
>part I liked)...it would be a shame to miss part of the second fly-by.
>

The Gaspra playback will not inhibit Galileo's data collection for the
second Earth flyby.  In fact, a similiar thing was already done with the first
Earth flyby, where the Venus data was played back just prior to the
flyby.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |     Jet Propulsion Lab |
  ___| | | | |__) |/  | | |__   M/S 301-355        | "Imagination is more
 /___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | important than knowledge"
 |_____|/  |_|/       |_____|/                     | Albert Einstein

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

Date: 26 Jun 91 10:53:53 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!bu.edu!transfer!lectroid!sw.stratus.com![e-mail]  (Tarl Neustaedter)
Subject: Aviation Week on Galileo

Excerpted From Aviation Week, June 24, page 54

After mentioning that the Oct. 29 Gaspra encounter will be recorded and
not broadcast directly (regardless of whether they free the antenna soon,
due to planning restrictions), a comment on why the antenna is stuck:

     High friction caused by galling between standoff pins on the antenna
   ribs and their conical receptacles on the antenna center structure is
   the likely cause for the stuck 16-ft-dia antenna, according to William
   J. O'Neil, Galileo project manager at the Jet Propulsion Laboratory.
   Differential heat expansion between the graphite ribs and the
   aluminum/beryllium center structure is believed to have locked some
   of the titanium pins in the receptacles as the center structure cooled
   and shrunk when Galileo traveled away from the Sun.

     But as the antenna ribs were driven open, the stuck ribs bent, rotating
   the pin forces from the top to the bottom of the receptacle, according
   to the latest scenario. Previously, engineers thought the center
   structure should be warmed and expanded to free the ribs, and this was
   tried unsuccessfully in late May. Now they think the center structure
   should be contracted because the main loads are believed to be on the
   bottom, instead of the top, of the receptacles.

     Pointing Galileo's high-gain antenna away from the Sun should provide
   enough cooling, and this may be done this summer. Engineers are also
   studying the natural frequency of the ribs and how they might be moved
   to jiggle them free.

[Perhaps having it play Strauss' Also Sprach Zarathustra? :-) ]

Anyway, they also show a self-portrait of galileo by it's infrared
mapping spectrometer, but from before the attempted antenna deployment.
Terrible resolution, but interesting that Galileo can take "pictures"
of itself.
--
         Tarl Neustaedter    [e-mail]
         Marlboro, Mass.    Stratus Computer
Disclaimer: My employer is not responsible for my opinions.

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

Date: 26 Jun 91 12:55:12 GMT
From: dftsrv!amarna.gsfc.nasa.gov![e-mail]  (Charles Packer)
Subject: Asteroid grazed atmosphere in 1972?

Last Tuesday there was an article about the danger of an
asteroid hitting Earth published in the New York Times.
It contains this statement:

  "In 1972 a large asteroid, estimated at up to 260
   feet in diameter, or nearly the length of a football
   field, zipped through the upper atmosphere over the
   northern United States and Canada, blazing across the
   sky in a daylight fireball witnessed by thousands of
   people before it re-entered space."

I checked the Times's own annual Index for 1972 and found
nothing about this under any related heading. There was one
occurrence mentioned in which (have you stopped laughing
about the 260-foot "large asteroid?") "400 shooting meteors"
were seen over Japan on Oct. 8.

Anybody know if there's anything to the asteroid story?

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

Date: 26 Jun 91 19:50:52 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!think.com!snorkelwacker.mit.edu!bloom-picayune.mit.edu![e-mail]  (Matthew T Velazquez)
Subject: Stanford Mars Landing Report Available?

From a recent posting in clari.tw.space:

>        WASHINGTON (UPI) -- An international effort could land the first human
>exploration team on Mars and establish a permanent base on the Red
>Planet within 21 years, a report concluded Wednesday.

Does anybody know where I could get my hands on a copy of this report? I have
several graduate projects from 1985 to describe the establishment of a Mars
base in conjunction with a lunar base, asteroid mining, and the space station,
and I would be very interested in seeing what the guys from Stanford and the
USSR have to say about it in 1991.

Any help at all would be appreciated.

AtDhVaAnNkCsE,

                T Velazquez
                MIT Aero/Astro
                [e-mail]
"The art of engineering is knowing when to lie, and by how much."
                -Ken Meltsner

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

Date: 26 Jun 91 21:38:40 GMT
From: agate![e-mail]  (EUVE jobs)
Subject: Research asst. positions w/NASA satellite project, UC Berkeley


                   Map the Unseen Universe

The Extreme Ultraviolet Explorer (EUVE) Project  is looking for
talented  and  enthusiastic  professionals  to join our team in
exploring and documenting stars and galaxies as they have never
been seen before.

EUVE is a NASA satellite scheduled for launch in December 1991.
Its  four  telescopes  were  designed  and  built  at the Space
Sciences Laboratory of the University of California, Berkeley.
These high-tech instruments will scan the sky in the first-ever
study of  the extreme ultraviolet,  a band of the spectrum that
cannot  be  seen  from  Earth.   Discoveries  await  us in this
previously unexplored region of space.

Among the challenges of the EUVE mission  is the development of
software to interpret the data gathered by the satellite.  This
software  will be used to study  the entire sky, creating a map
of the locations and intensities of stars and other astronomical
sources  emitting EUV radiation,  and to  convert photon  events
into meaningful data for in-depth scientific study.

The following positions are available:

                        STAFF POSITIONS

These jobs  require a  background in Astronomy,  Physics, Math,
Computer Science, or a related field.  In addition,  applicants
must  be  familiar  with  the  UNIX  operating system  and have
experience with C and/or FORTRAN.  Multiple positions are
available.


RESEARCH ASSISTANT
Box # 12-215-218-22 Q

Work  on  a  scientific  team  for reducing  and analyzing EUVE
spectrometer  data for the  Guest Observer Program.  Coordinate
data   processing   activities   of   space-  and  ground-based
astronomical  observations  and  assist  in  using software for
scientific analysis of data.   Integrate instrument calibration
data  into  an  evolving   software  package;  test  integrated
astronomical software. Assist with evaluation of Guest Observer
proposals.

REQUIRED:  Related work experience on an astronomical satellite
           project.
DESIRABLE: Knowledge of IRAF.


RESEARCH ASSISTANT
Box # 03-214-218-22

Support  the  processing  of  EUVE  satellite  data  from  raw
telemetry  into  skymaps,  source catalogs, time-tagged photon
files, and spectra.  Monitor  the  data  processing flow, help
detect  previously  unknown  EUV   sources,   assist   in  the
understanding  of  spacecraft  aspect,   produce  skymaps   in
multiple bandpasses,  produce a history file database, develop
data processing strategies with the staff scientists.

REQUIRED:  Experience with C or Bourne shell scripts.
DESIRABLE: Experience  with  data  reduction  and  analysis
           techniques with astronomical packages.

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

All jobs are located  at the  Center for EUV Astrophysics on
the  UC  Berkeley  campus.  To  apply,  send  a  resume  and
three  references to the UC Employment Office, 2539 Channing
Way, Berkeley, CA 94720.   Cite the box number given for the
position.

You may also send an *informational* copy of your resume and cover
letter by email to [e-mail].  However, official
applications MUST go through the UC Employment Office at the
address given above.  Please confirm in your email to euvejobs
that you have followed the official application process.



               THE UNIVERSITY OF CALIFORNIA IS AN
          EQUAL OPPORTUNITY AFFIRMATIVE ACTION EMPLOYER

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

Date: 26 Jun 91 18:44:31 GMT
From: mailer.cc.fsu.edu!geomag![e-mail]  (Joe Cain)
Subject: Re: Aurora geometry

In article <[e-mail]> [e-mail] (Tony Arnerich) writes:
>The Aurora is an atmospheric phenomenon (ionosphere? stratosphere?),
>therefore it is a local phenomenon. As I understand it, it generally
>takes the form of a ring, more or less centered on the magnetic pole.

    A good reference for the novice to such matters is the little
book "The Solar Wind and the Earth" (Kamidi and Akasofu, eds)
published in 1987 by Terra. The reference list in their chapter also
mentions the older book by Jones, "The Aurora" 1974.

    The aurora is a map of a portion of the magnetosphere into
the polar regions. The bottom of the glow is almost always about 100
km, though the upper regions can range from 400 to over 1000 km. Thus
it spans from the ionospheric E layer into the F and is never a
stratospheric phenomenon. The direction of the rays is that of the
local magnetic field at that altitude.

    The auroral oval is a statistical concept, and besides being
not a circle, centers according to the field at higher altitudes, or
generally shifted towards the dark side maybe 300 km from the dipole
pole (sounds redundant).

    There are observed "theta" aurorae from the Dynamics Explorer
satellite which form a complete ring, though significant changes occur
on the portion that happens to be experiencing a "substorm." The
patterns are similar to the statistical, but there is a different
appearance on the day and night portions. The latitude of the glow
depends on the stage of the substorm, intensity, local time, etc.

Joseph Cain        [e-mail]
[e-mail]        scri::cain

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

Date: 26 Jun 91 21:27:44 GMT
From: agate![e-mail]  (EUVE jobs)
Subject: Programmer positions w/NASA satellite project at UC Berkeley


                   Map the Unseen Universe

The Extreme Ultraviolet Explorer (EUVE) Project  is looking for
talented  and  enthusiastic  professionals  to join our team in
exploring and documenting stars and galaxies as they have never
been seen before.

EUVE is a NASA satellite scheduled for launch in December 1991.
Its  four  telescopes  were  designed  and  built  at the Space
Sciences Laboratory of the University of California, Berkeley.
These high-tech instruments will scan the sky in the first-ever
study of  the extreme ultraviolet,  a band of the spectrum that
cannot  be  seen  from  Earth.   Discoveries  await  us in this
previously unexplored region of space.

Among the challenges of the EUVE mission  is the development of
software to interpret the data gathered by the satellite.  This
software  will be used to study  the entire sky, creating a map
of the locations and intensities of stars and other astronomical
sources  emitting EUV radiation,  and to  convert photon  events
into meaningful data for in-depth scientific study.

The following positions are available.

                        STAFF POSITIONS

Both jobs  require  a  background in Astronomy,  Physics, Math,
Computer Science, or a related field.  In addition,  applicants
must  be  familiar  with  the  UNIX  operating system  and have
experience with C and/or FORTRAN.


SCIENTIFIC PROGRAMMER
Box # 05-212-217-22 Q

Work with a team of programmers and scientists to develop novel
algorithms  and  software to analyze the  imaging data from the
EUVE  all-sky  survey.   Both production  programs,  which must
operate autonomously  in a real-time pipeline,  and interactive
programs are included  in  the  scope  of  this  project.  This
experienced  programmer  will  work  on  original  methods  for
finding  new astronomical objects amid the noise of geophysical
and astronomical background, construction and display of false-
color  sky  maps,  measurement of positions  and intensities of
stars  using  complex  point spread functions,  quantifying the
time  variability of  sources,  and  detection  of  diffuse EUV
emission structures.

REQUIRED: Demonstrated scientific programming ability in C.
Multiple positions available.


SCIENTIFIC PROGRAMMER
Box # 07-200-22 Q

Work closely with a small team of scientists to design portable
software for the project's Guest Observer Program.  Responsible
for  collaborating  with  scientists  to  implement  innovative
algorithms for image  processing of  event-oriented data.  This
position requires  a  programmer who  can work independently to
develop  software  to analyze spectrometer data;  perform image
processing  to  calibrate   observations;   and   develop  user
interfaces that  allow scientists to select observational data.
Assist with  theoretical modeling  to solve  complex  tasks  of
scientific data analysis.

REQUIRED:  Demonstrated scientific programming ability, preferably in C.
DESIRABLE: Familiarity with IRAF.


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

All jobs are located  at the  Center for EUV Astrophysics on
the  UC  Berkeley  campus.  To  apply,  send  a  resume  and
three  references to the UC Employment Office, 2539 Channing
Way, Berkeley, CA 94720.   Cite the box number given for the
position.

You may also send an *informational* copy of your resume and cover
letter by email to [e-mail].  However, official
applications MUST go through the UC Employment Office at the
address given above.  Please confirm in your email to euvejobs
that you have followed the official application process.



               THE UNIVERSITY OF CALIFORNIA IS AN
          EQUAL OPPORTUNITY AFFIRMATIVE ACTION EMPLOYER

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

End of SPACE Digest V13 #796
*******************