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Date: Wed,  4 Jul 1990 01:55:17 -0400 (EDT)
Subject: SPACE Digest V12 #12

SPACE Digest                                      Volume 12 : Issue 12

Today's Topics:
       Re: Hubble Investigation Board Named (Forwarded)
   Your space program (was: Re: More on NASA 91 Appropriation Vote)
Re: NASA announces next steps in Space Exploration Outreach Program (F
               Weather gifs/Apple IIgs
          A report on Giotto's earth swingby
          A report on Giotto's earth swingby
           Re: NSS protests Chinese launch pricing

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: 3 Jul 90 16:35:08 GMT
From: vax8530![e-mail]  (T. Joseph Lazio, Cornell University)
Subject: Re: Hubble Investigation Board Named (Forwarded)

In article <[e-mail]>, [e-mail] (Ron Baalke) writes:
>          HUBBLE INVESTIGATION BOARD
>      The board will be chaired by Dr. Lew Allen, Director, Jet
> Propulsion Laboratory, Pasadena, Calif.  The other members of the
> board are:
>
>       Charles P. Spoelhof
>         (Retired) Vice President, Eastman Kodak Co.
>         Pittsford, N.Y.
>
>       George A. Rodney
>         Associate Administrator for Safety and Mission Quality
>         NASA Headquarters, Washington, D.C.
>
>       John D. Mangus
>         Head, Optics Branch, Space Technology Division
>         NASA Goddard Space Flight Center, Greenbelt, Md.
>
>       Dr. R. (Bob) Shannon
>         Professor of Astronomy, Optical Sciences Center
>         University of Arizona, Tucson
>
>       Dr. Roger Angel
>         Professor of Astronomy, Steward Observatory
>         University of Arizona, Tucson

      Having read _What Do You Care What Other People Think?_ by
      Feynmann, I am curious to know how many of these people
      are really independent of NASA.  For those who have not read
      the book, Feynmann was (privately) told that he was the only
      independent member of the Rogers Commission; all the other
      members had some ties to NASA.  Feynmann used the independence
      to ask tough questions; he was not afraid of embarrassing anybody.

--
      T. Joseph Lazio
      Cornell University  [phone]
      [e-mail]
      [e-mail]

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

Date: 3 Jul 90 08:50:00 GMT
From: agate!agate![e-mail]  (William Baxter)
Subject: Your space program (was: Re: More on NASA 91 Appropriation Vote)


In article <[e-mail]> [e-mail] (David Anderman) writes:

>I'm curious to know the mechanics of how Andy Cutler gets to determine
>the final mission architecture of the SEI? Or, for that matter, how you
>or I could participate in the definition of the project.

Dr. Cutler will have his input through the AIAA working group on the
Assesment of Innovative Technologies for the Exploration of Space, of
which he is a member.  He says that they have not received enough ideas,
perhaps because the closing date is early.

Dr. Cutler remains concerned that people taking a cynical view will
percieve the current exercise as a bureaucratic game designed to make
in-house ideas look better by opening the door to public input just long
enough to collect a few bad ideas.  He would like to receive your
credible and carefully considered proposals.

Write them up and send them to him:

Dr. Andrew H. Cutler
Assistant Research Professor
University of Arizona
Space Engineering Research Center
4717 E. Ft. Lowell
Tucson, AZ 85712

--
William Baxter

ARPA: web@{garnet,brahms,math}.Berkeley.EDU
UUCP: {sun,dual,decwrl,decvax,hplabs,...}!ucbvax!garnet!web

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

Date: 3 Jul 90 12:16:40 GMT
From: mcsun!ukc!icdoc![e-mail]  (Simon E Spero)
Subject: Re: NASA announces next steps in Space Exploration Outreach Program (F

>>>>> On 30 Jun 90 03:46:36 GMT, [e-mail] (Craig E. Ward) said:

cew> In article <[e-mail]> [e-mail]
cew> (Craig E. Smith) writes:
>
>...expansion of English power was at least in part based on the
>plundering, and exploitation of these other colonies....

cew> The part that played was very small.  The real reason English colonies were
cew> stronger, and why most North Americans speak English, is that the English
cew> sent families.

Rubbish! The real reason why the English colonies succeeded is our effortless
superiority.

--
------------------------------------------------------------------------------
[e-mail] | [e-mail] | ..!ukc!slxsys!cix!sispero
------------------------------------------------------------------------------
The Poll Tax.    |`And in my mind that's all you'll ever be|DoC,Imperial
I'm Not. Are you?|  Spongiform Encepalophaphy' T Tikkaram  |College,London SW7
------------------------------------------------------------------------------

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

Date: 28 Jun 90 01:55:05 GMT
From: att!mcdchg!laidbak!obdient!vpnet![e-mail]  (Jason J. Levit)
Subject: Weather gifs/Apple IIgs


  I see there was a post on how to get the weather images to work on a
  Mac, but I own an Apple IIgs, and I'd like to get the same thing.  I
  know it can be done, but I'm having problems

  Is there anyone else out there that is getting the gifs for an apple
  IIgs, or knows how to do it?  My major problem is downloading them
  from the unix system here to my IIgs.  It seems they are in the
  binary format, but I can't get them to download right.

  Thanks for the help!

------------------------------------------------------------------------------
:     A good planet is hard to find.                Jason J. Levit           :
:         Let's save this one!                      [e-mail]   :
------------------------------------------------------------------------------
                               APPLE II FOREVER!

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

Date: 3 Jul 90 15:01:55 GMT
From: mcsun!unido!mpirbn![e-mail]  (Daniel Fischer)
Subject: A report on Giotto's earth swingby

Just 24 hours ago, earth was visited by a spacecraft that had left here on an
Ariane rocket exactly 5 years ago: GIOTTO. The following article (which I've
just decided to spontaneously submit to Sky & Telescope, so please do not
distribute it yet!) summarizes what I've learned on a nice news conference
at the European Space Operations Center at Darmstadt, 3 hrs after the swingby:


         Earth Swingby: Giotto on its way to Comet Grigg-Skjellerup!

It was an absolute first in space history: a spacecraft returning to earth from
the depths of the solar system, to receive a gravity assist for a new job. On
2 July 1990 at 10:01:18 Universal Time, precisely five years after its launch,
the European Giotto spacecraft approached earth to 22730 km over Australia,
raced past earth in a wide hyperbola with a speed of 6.3 kilometers per second,
and changed its orbit from one inside earth's to one outside - to meet comet
Grigg-Skjellerup on 10 Juli 1992 at 15:30 Universal Time +/- a few minutes.

One week after its spectacular encounter with Halley's comet on 14 March 1990
Giotto had been put into a peculiar orbit that went 6 times around the sun
while earth performed five orbits. On 2 April 1986 Giotto had been put into
hibernation and was on its own for the next 4 years. Amazingly it was on the
very first attempt on 19 February 1990 that the spacecraft replied to a wake-up
call transmitted by NASA's Deep Space Network 70-meter antennas. At this point
Giotto was still 102 Million km from earth, and only its Low Gain Antenna was
working. It took another six tense days until the s/c could be commanded to
also turn its parabolic High Gain Antenna towars earth, and a full two months
more until the detailed checkout of the spacecraft systems and science instru=
ments could begin. Giotto was too hot, initially, only 0.75 AU from the sun,
with the thermal systems badly damaged in the Halley coma, but in April it was
cool enough to work with.

As it turned out, the essential systems of the s/c were in remarkably fine
state despite their 5 years in space (and a nominal lifetime of just 13
months). But several redundancies were lost, and no mistakes can be afforded
now. The results from the 11 scientific experiments were mixed. Completely out
of work are the Neutral Mass Spectrometer and regrettably also the Halley
Multicolor Camera, the only imaging system on board. Its electronics and
mechanics are well, but a part of the baffle tube is stuck in front of the
optics - all images returned are just black.

Two other instruments are fine but cannot be used at Grigg-Skjellerup: for the
Ion Mass Spectrometer, the flyby velocity (14km/s instead of the 68 km/s at
Halley's) is too slow to get results, and the entrance window of the PIA dust
analyser points into a direction that was useful only at Halley's. Seven
instruments, however, are fully or almost fully at work! There is the Energetic
Particles Analyser, the Optical Probe Instrument, the Magnetometer (all three
just as new), the Johnstone Plasma Analyser and the Reme Plasma Analyser (both
partially damaged) and the Dust Impact Detection System, which can still count
dust particles. The radio science is well, also, since it needs just a strong
radio signal to get information from doppler shifts and the like.

This means a shift of interest for Giotto from the questions asked at Halley's:
the main interest now is in plasma physics. As the Giotto scientists summarize
in a recent report to ESA's Science Programme Committee, there will be
 > characterisation of the changing features of the solar-wind flow (by JPA),
 > observation of cometary pick-up ions and anomalous acceleration (JPA,EPA),
 > determination of electron densities (RPA),
 > observation of upstream waves, determination of the locations of the various
   boundaries (bow shock, ionopause, cometopause etc.), and observation of the
   magnetic pile-up region and cavity immediately around the nucleus (MAG),
 > determination of the dust spatial density and size distribution and the
   optical properties of the dust grains (DID and OPE),
 > and the detection of discrete gaseous emissions, as well as the determi=
   nation of combined dust and gas densities (OPE and Radio Science).
The ESA committee was impressed enough to vote for the GIOTTO EXTENDED MISSION
on 13 June; while the roughly 7 million $ spent for reactivating Giotto have
been taken from ESA's science budget, the approx. 10 million needed for
executing the Extended Mission will have to be collected from ESA's member
states separately. It is an 'Optional Programme', no country is forced to pay
for Giotto's second appointment, but the changes for financing are quite good.

While the plasma investigations are basic research with sometimes little
interest in the comet itself (it'll just serve as a small, gas-emitting body
thrown into the solar wind), the dust studies also have an engineering side.
The inactive Grigg-Skjellerup is much more like the preferred target
comets of future space missions than the active Halley. Thus it offers the
last opportunity to study the dust env used up,
and the technicians and scientists will be on many other projects already
(even in 1990 is proved hard to reunite the teams of 1986). But in about 50
years from now, Giotto will once more return to the vicinity of earth: it
might be caught (if somebody will still care then) and end up in a space
museum...

      (C) 1990 by Daniel Fischer --- comments to: [e-mail]
                  (I'll be on vacation within 12 hours, though, til 28 July)

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

Date: 3 Jul 90 15:04:13 GMT
From: mcsun!unido!mpirbn![e-mail]  (Daniel Fischer)
Subject: A report on Giotto's earth swingby

Just 24 hours ago, earth was visited by a spacecraft that had left here on an
Ariane rocket exactly 5 years ago: GIOTTO. The following article (which I've
just decided to spontaneously submit to Sky & Telescope, so please do not
distribute it yet!) summarizes what I've learned on a nice news conference
at the European Space Operations Center at Darmstadt, 3 hrs after the swingby:


         Earth Swingby: Giotto on its way to Comet Grigg-Skjellerup!

It was an absolute first in space history: a spacecraft returning to earth from
the depths of the solar system, to receive a gravity assist for a new job. On
2 July 1990 at 10:01:18 Universal Time, precisely five years after its launch,
the European Giotto spacecraft approached earth to 22730 km over Australia,
raced past earth in a wide hyperbola with a speed of 6.3 kilometers per second,
and changed its orbit from one inside earth's to one outside - to meet comet
Grigg-Skjellerup on 10 Juli 1992 at 15:30 Universal Time +/- a few minutes.

One week after its spectacular encounter with Halley's comet on 14 March 1990
Giotto had been put into a peculiar orbit that went 6 times around the sun
while earth performed five orbits. On 2 April 1986 Giotto had been put into
hibernation and was on its own for the next 4 years. Amazingly it was on the
very first attempt on 19 February 1990 that the spacecraft replied to a wake-up
call transmitted by NASA's Deep Space Network 70-meter antennas. At this point
Giotto was still 102 Million km from earth, and only its Low Gain Antenna was
working. It took another six tense days until the s/c could be commanded to
also turn its parabolic High Gain Antenna towars earth, and a full two months
more until the detailed checkout of the spacecraft systems and science instru=
ments could begin. Giotto was too hot, initially, only 0.75 AU from the sun,
with the thermal systems badly damaged in the Halley coma, but in April it was
cool enough to work with.

As it turned out, the essential systems of the s/c were in remarkably fine
state despite their 5 years in space (and a nominal lifetime of just 13
months). But several redundancies were lost, and no mistakes can be afforded
now. The results from the 11 scientific experiments were mixed. Completely out
of work are the Neutral Mass Spectrometer and regrettably also the Halley
Multicolor Camera, the only imaging system on board. Its electronics and
mechanics are well, but a part of the baffle tube is stuck in front of the
optics - all images returned are just black.

Two other instruments are fine but cannot be used at Grigg-Skjellerup: for the
Ion Mass Spectrometer, the flyby velocity (14km/s instead of the 68 km/s at
Halley's) is too slow to get results, and the entrance window of the PIA dust
analyser points into a direction that was useful only at Halley's. Seven
instruments, however, are fully or almost fully at work! There is the Energetic
Particles Analyser, the Optical Probe Instrument, the Magnetometer (all three
just as new), the Johnstone Plasma Analyser and the Reme Plasma Analyser (both
partially damaged) and the Dust Impact Detection System, which can still count
dust particles. The radio science is well, also, since it needs just a strong
radio signal to get information from doppler shifts and the like.

This means a shift of interest for Giotto from the questions asked at Halley's:
the main interest now is in plasma physics. As the Giotto scientists summarize
in a recent report to ESA's Science Programme Committee, there will be
 > characterisation of the changing features of the solar-wind flow (by JPA),
 > observation of cometary pick-up ions and anomalous acceleration (JPA,EPA),
 > determination of electron densities (RPA),
 > observation of upstream waves, determination of the locations of the various
   boundaries (bow shock, ionopause, cometopause etc.), and observation of the
   magnetic pile-up region and cavity immediately around the nucleus (MAG),
 > determination of the dust spatial density and size distribution and the
   optical properties of the dust grains (DID and OPE),
 > and the detection of discrete gaseous emissions, as well as the determi=
   nation of combined dust and gas densities (OPE and Radio Science).
The ESA committee was impressed enough to vote for the GIOTTO EXTENDED MISSION
on 13 June; while the roughly 7 million $ spent for reactivating Giotto have
been taken from ESA's science budget, the approx. 10 million needed for
executing the Extended Mission will have to be collected from ESA's member
states separately. It is an 'Optional Programme', no country is forced to pay
for Giotto's second appointment, but the changes for financing are quite good.

While the plasma investigations are basic research with sometimes little
interest in the comet itself (it'll just serve as a small, gas-emitting body
thrown into the solar wind), the dust studies also have an engineering side.
The inactive Grigg-Skjellerup is much more like the preferred target
comets of future space missions than the active Halley. Thus it offers the
last opportunity to study the dust enviroment of such a nucleus first-hand,
before missions like Comet Rendezvous Asteroid Flyby and Comet Nucleus Sample
Return dare to actually orbit one resp. to even land and dig on one. Grigg-
Skjellerup orbits the sun every 5.1 years, with a perihelion distance of .99
and an aphelion distance of 4.93 AU: it belongs to Jupiter's familiy and often
experiences close encounters with this giant. The last one, in 1964, e.g.
altered G-S' inclination from 8 degrees to the present 21 degrees. While the
last apparition in 1987 was well observable and resulted in good astrometry
(and also lots of amateur sightings at 11th mangnitude), the 1992 apparition
will be extremely poor, with only 14mag and almost no visibility from the
Northern hemisphere. This will surely hamper astrometric measurements of its
precise position and thus the navigation for Giotto, but ESA still hopes to
approach the nucleus by less than 1000 km. The chance for a hit on the
nucleus is very remote, of course, but *if* it should happen , there would
be quite a display - according to estimations by Fred Whipple...

Giottos Swingby at earth had been prepared by 25 small attitude and orbit
maneuvers that took just 6 kg of its Hydrazine fuel, 18 kg is still left in
the tanks. The final correction on 30 June had put Giotto on such a fine
trajectory that it missed the point of closest approach to earth by just 5 km
and arrived only 2 seconds early. Only a minor orbital tweak will be required
before another two-year hiberation will begin for the spacecraft, which is
not to be reawakened before April of 1992. The gravity assist was absolutely
essential for reaching the Grigg-Skjellerup rendezvous point: it gave Giotto
an additional 3.1 km/s of orbital energy (while unmeasurably slowing down the
earth, of course) - buring all fuel on board at once would just have
resulted in a velocity increase of 16 meters per second.

And what is going to happen after the Grigg-Skjellerup adventure? There will
definitively be no third comet on the list: fuel will by then be used up,
and the technicians and scientists will be on many other projects already
(even in 1990 is proved hard to reunite the teams of 1986). But in about 50
years from now, Giotto will once more return to the vicinity of earth: it
might be caught (if somebody will still care then) and end up in a space
museum...

      (C) 1990 by Daniel Fischer --- comments to: [e-mail]
                  (I'll be on vacation within 12 hours, though, til 28 July)

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

Date: Wed, 4 Jul 90 00:07:41 EDT
From: [e-mail] (Keith F. Lynch)
To: utgpu!utzoo![e-mail]
Subject: Re: NSS protests Chinese launch pricing
Cc: [e-mail], [e-mail]

> Complaints about the pricing being too low always seem to be
> implicitly based on the assumption that Chinese costs are similar
> to those of the Western suppliers, which is clearly untrue, because
> they provide poorer service in simpler ways with lower-cost labor.

Of course.  Since there is no free market in labor in China, the
government has what amounts to slave labor.

I don't see that it's even meaningful to say whether this constitutes
a subsidy or not.  Their whole economy is twisted beyond recognition.
And I have never understood why people who protest at dealing with
South Africa don't seem to mind the far vaster and more universal
tyranny of the communist world.
                                ...Keith

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

End of SPACE Digest V12 #12
*******************