Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v09_4/v9_478.txt

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Subject: SPACE Digest V9 #478

SPACE Digest                                      Volume 9 : Issue 478

Today's Topics:
               Garage Satelite
            Re: Russians bomb U.S.
               Astronomy digest
       Magellan Status for week of 06/06/89 (Forwarded)
           Re: CRESCENT SIGHTING - Sun 4 June 1989
               Re: SPACE Digest V9 #474
 Re: CRESCENT SIGHTING - Sun 4 June 1989, Orbital details etc. (Long)
              Re: Space telescope optics
               NSS Space Hotline Update
----------------------------------------------------------------------

ReSent-Message-ID: <[e-mail]>
ReSent-Date: Wed,  7 Jun 89 09:36:47 -0400 (EDT)
ReSent-From: Ted Anderson <[e-mail]>
ReSent-To: [e-mail], Space <[e-mail]>
Sender: "Bernard_DeGruchy.WBST129"@Xerox.COM
Date: 30 May 89 05:40:06 PDT (Tuesday)
Subject: Garage Satelite
From: "Bernie_DeGruchy.WBST129"@Xerox.COM
Reply-To: [e-mail]

 To whom it may concern:

       Somebody posted a notice seeking people that were interested in
designing a satelite for space and were looking for volunteers to join the
effort.  I read it and deleted it and then thought about it.  Well count me
in.
       My net address expires the end of June or before.  I am working a
contract which expires then.  However I have a home address which I can be
reached at and since I doubt that you'll be able to reach me by net in time
(the system is so slow here, besides we don't get all the postings here
anyway) here it is:

            Bernard DeGruchy
            4321 Ridge Road West
            Rochester, New York
                    14626

       I am looking forward to hearing from you.  I am an Electronic
Technician who will be unemployed after June 30, 1989 so I will have time
on my hands if I can help out. (Hopefully this won't last long.)

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

Date: 6 Jun 89 22:15:25 GMT
From: xanth![e-mail]  (Frank C. Paterra)
Subject: Re: Russians bomb U.S.

In article <[e-mail]>, [e-mail] (Wayne D. T. Johnson) writes:
>
> Another headline from the local news:
> (sorry but they didn't give much detail and what little they did give I
> have forgotten)
>
> Upper stage from Proton booster crashs in U.S. near Canadian border.
>
> Any one have any details?

Please post any information!!  Also, what other large objects have
re-entered and crashed within the U.S.?

Frank Paterra
[e-mail]

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

Date: Tue, 6 Jun 89 18:23:11 EDT
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Astronomy digest


[This is a highly condensed summary of selected items from the June, 1989
issue of Astronomy Magazine. See the magazine for details and good color
photographs.]

Editorial describing the difference between radioisotope thermal generators
(RTGs) and nuclear reactors. Explanation of why RTGs are safer, and why they
are necessary for work in the outer solar system and on the surface of Mars.

Voyager 2 images from 195 million miles reveal rotating cloud patterns on
Neptune. Flyby is scheduled for August 25, 3000 miles above the cloud tops.

A brief description of the Soviet astronomical facilities near Zelenchukskaya.
The RATAN 600 radiotelescope is a 600-meter ring made of 900 "flat, rectangular"
movable reflectors that focus on a central collector. (Arecibo has greater
collection area.) The 6-meter optical telescope has only about 170 nights
per year good for observing, with average seeing of 1 arcsecond. [The primary
mirror is very thick, and ambient temperatures must remain constant for a
long time (hours) for the mirror to focus properly.]

Description of a model of the early solar system, in which the planets are
made up of medium-sized "planetesimals". [See previous posting by Dennis
Brantly. If, as suspected, earth life was wiped out and started over several
times, this would be good news to those who hope to find life elsewhere,
since it would be the first direct evidence that the initiation of life
processes is not a "once in the universe" event.]

Very good article on the operational algorithm of the Hubble Space Telescope
[also described by Dennis Brantly]. Pointing at the sun would destroy the
instruments, but there is an automatic shutter override for safety. Pointing
near a bright object lets extraneous light into the tube. The telescope can
not be used within 50 degrees of the sun, or 20 degrees of the bright side
of the earth. The goal is to get the most and the best observations possible
within the position and time constraints. HST has an on-board computer which
handles most of the minute-to-minute control. For guidance, a catalog of
15 million stars has been produced. During a time exposure, HST must remain
stable to within .007 arcsecond [!] by use of reaction wheels.

Article covering several methods for estimating the distance to other
galaxies. This is a hot topic, because it affects the cosmological theories,
and some of the measures differ by a factor of two or more.

Saturn and Neptune pass within 18 minutes of each other on June 24. This may
make it easier for amateurs to locate Neptune, since Saturn isn't hard to find.

Timetables and charts for locating the planets and their moons.

Saturn will occult the star 28 Sagittarii slightly before 2 AM EDT on July 3.
The star should flicker as it passes through the rings. Astronomers use
occultations to probe planetary rings and atmospheres.

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

Date: 6 Jun 89 17:26:46 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Magellan Status for week of 06/06/89 (Forwarded)


                     MAGELLAN WEEKLY STATUS
                             June 6


     This is a weekly status report. The next report will be
issued June 12.

     The spacecraft continues to operate routinely with twice
daily momentum wheel desaturations and once-a-day star
calibrations.

     Radio calibration tests will begin this month.

     Magellan engineers are periodically rolling the spacecraft
180 degrees about the Medium-Gain Antenna axis to obtain Rocket
Engine Module (REM) temperature data to update the temperature
model. Again, the higher than expected REM temperatures will
constrain use of the High-Gain Antenna and, consequently, the
Deep Space Network's Very Long Baseline Interferometry (VLBI)
tests during the cruise. While this is not considered to be a
major problem, REM temperatures could constrain mapping
operations in the first cycle of an extended mission.

     Corrections to ground attitude control software have been
made which are believed to have solved an attitude knowledge
problem. Updates will be added to the flight attitude software
on Friday, June 9. One possible result of the attitude control
problem is mispointing the High-Gain Antenna on the order of one-
half a degree, which results in a small loss in the downlink
signal. The loss is not a problem at the present time because
there is more than adequate margin in the receiving antenna. Once
the attitude control knowledge problem is solved and the
subsystem calibrated, a High-Gain Antenna calibration will be
made to take out any mechanical or electrical offset.

     A technical briefing is scheduled for June 13 on the
attitude control knowledge problem and whether to continue
momentum wheel desaturations twice a day.

     The Solid Rocket Motor (SRM) temperature is at 31 degrees C
(87.8 F), close to the redline limit of 33 C (91.4 F) as the
nozzle points closer to the sun. This is being watched closely.

     Magellan has moved inward from Earth's orbit toward the
sun. Magellan was fired by the IUS in the opposite direction to
Earth's flight to slow the spacecraft down so it would fall
inward toward the orbit of Venus. In July the spacecraft will
begin to speed up relative to Earth and about August 1 it will
have caught up with Earth so that the sun, spacecraft and Earth
will be almost in a straight line. At about noon of each day, if
you could see Magellan, it would be overhead with the sun in the
background.



     SPACECRAFT
     Distance From Earth (mi)                    4,502,212

     Velocity Geocentric                         5,291 mph
              Heliocentric                      60,719 mph

     One Way Light Time                           24.2 sec

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

Date: 5 Jun 89 21:25:00 GMT
From: sun-barr!texsun!texbell!merch!cpe!hal6000!trsvax![e-mail]
Subject: Re: CRESCENT SIGHTING - Sun 4 June 1989


When are we going to see Salmon Rushdie sightings in sci.space?

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

Date: Tue, 6 Jun 1989 12:27-EDT
From: [e-mail]
Subject: Re: SPACE Digest V9 #474

>Sales of aerosol cans fell through the floor when the ozone-hole thing got into
> the headlines in the winter. Now, only a few months later you see labels
> claiming 'ozone friendly' on all sorts of products that contain anything that
> resembles a solvent. Car wax, shoe shine wax, aerosols, paint - you name it!
>
> Joe Public is forcing a *big* change in things here. Even the traditionally
> hard-nosed government we've got here at the moment has done some spectacular
> U-turns on certain things recently.

Yet another example of how markets react faster and with less
sensitivity to entrenched interests than governments....

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

Date: 6 Jun 89 15:59:26 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: CRESCENT SIGHTING - Sun 4 June 1989, Orbital details etc. (Long)

In article <[e-mail]> [e-mail] (John E Van Deusen III) writes:
>In article <[e-mail]>
>[e-mail] (Mohib N Durrani) writes:
>>       The survey results are to enhance the present ATMOSPHERIC MODEL
>>          and fine tune some parameters regarding SCATTERING/VISION.
>I should hope so.  If these are obsessive-compulsive religious
>machinations, perhaps Cat Stevens could help me out with my phone bill.

Well according to something in SCIENCE NEWS last year there is in fact
an ongoing research project in this area and the Muslims are providing
the impetus - lots of folks want to know about atmospheric refraction
and scattering as it relates to composition of the various layers; only
the Muslims need to do it for Allah's sake!

There's actually a tradition to this - the great Arab astronomers of
medieval times were glorifying Allah with their work too.  Whatever works...

I agree the volume of posting is excessive.  Perhaps the folks at Columbia
could switch to a mailing list and post a short pointer here.
--
Tom Neff                UUCP:     ...!uunet!bfmny0!tneff
    "Truisms aren't everything."    Internet: [e-mail]

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

Date: 6 Jun 89 04:27:28 GMT
From: [e-mail]  (David Palmer)
Subject: Re: Space telescope optics

In article <[e-mail]> [e-mail] (John Roberts) writes:
>
>Several people have posted to the net stating that the Hubble Space Telescope
>could not focus on an object as close as the earth. I tend to be somewhat
>skeptical of this claim, because of the phenomenon known as depth of field.
...
> but a few guesses
>and application of the formulas used for cameras suggest that the
>hyperfocal distance may be only a few miles. Does anyone have any better
>numbers?

It is easy to see that when you focus an optical system at infinity,
the circle of confusion of an image at a finite distance is the size
of the aperture at that distance.  (The circle of confusion, when convolved
with the point-spread-function of a point at infinity, gives the point-
spread-function for a source at the finite distance.  The psf is larger
than the larger of the psf at infinity and the circle of confusion)
Think of it a parallax across the mirror.

This means that the HST cannot see objects smaller than its 2.4 m mirror,
compared to the pie-plate size of a Spy-sat.  (CPU-intensive deconvolution
can improve both of these somewhat)

        David Palmer
        [e-mail]
        ...rutgers!cit-vax!tybalt.caltech.edu!palmer
    "Only 10% of the 4000 mile long coastline was affected."
        -Exxon's version of the oil spill as reported to stockholders

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

Date: 6 Jun 89 02:58:00 GMT
From: arisia!cdp![e-mail]
Subject: NSS Space Hotline Update


This is the National Space Society's Space Hotline for the week
ending June 4, 1989.

Vice President Dan Quayle, Chairman of the National Space
Council, reportedly stated during a luncheon meeting with
reporters on May 31st that the US will eventually win control of
space, and that he intends to be involved in some very difficult
decisions which will have to be made in regards to America's
future in space. He reportedly stated that he wants congressional
appropriators to understand that the administration wants to see
the Space Station Freedom program funded at an adequate level.
Quayle reportedly said that the space race is not over, that we
will "win" due to our superior technology and that much remains
to be done.  He went on to say that the White House will soon
reveal its long term strategy for space.

During his visit to London, President Bush issued a statement of
approval to maintain funding for the continuing operations of
Landsats 4 & 5 and the development and launching of Landsat 6.
Keeping Landsats 4 & 5 operating will cost $5 million for the
rest of FY'89, and $16 million for FY'90.  This decision was the
first policy recommendation made by the newly formed National
Space Council.

The Long Duration Exposure Facility which was deployed during the
STS-13 mission in April of 1984 is scheduled to be retrieved by
shuttle crews this December.  Once retrieved, the satellite will
provide critical data on the long term effects of space exposure
on various materials.  The LDEF, which is carrying 12 million
tomato seeds as well as 50 other scientific and technological
experiments, was originally scheduled to be retrieved in 1985.
Its retrieval was postponed at that time for a higher priority
mission, and then the Challenger disaster occurred before
retrieval could be rescheduled.  If the LDEF is not retrieved
during this December's mission it will re-enter the atmosphere
and burn up.

This week the House Appropriations Committee will begin debate on
the FY'90 spending bill, which will decide how much each of its
13 subcommittees will receive for FY'90 under the current budget
resolution.  The so-called 302b allocation is the block
allocation that goes to the House and Senate HUD-Independent
Agencies Subcommittee, which must allocate it between, NASA, HUD,
the Veterans Administration, EPA, and NSF, as well as others.
Currently, Housing and Veterans groups see the $2.1 Billion
program request for the Space Station as a prime target for cuts
to support increased funding for their own agendas.

The NSS family of organizations reminds spacers everywhere to
call and write Rep. Jamie Whitten, Chairman of the House
Appropriations Committee and the Chairman of the VA HUD-IA
subcommittee, Rep. Bob Traxler. Encourage them to support a
larger 302b block grant allocation for VA HUD-IA so that the
space station program gets fully funded for FY'90. Whitten's
phone number is 202-225-4306 and Traxler's is 202-225-2806. Space
station supporters can write to each at the U.S. House of
Representatives, Washington, DC 20515. For more details call
David Brandt at Spacecause [phone].

It has been revealed that former NASA Administrator James
Fletcher became a consultant to NASA the day after he retired.
His contract is for $41,920 and not exceeding 130 days, a NASA
work statement revealed.  He will advise Administrator designated
Richard Truly and other top NASA officials on programs and
projects which he possesses a critical knowledge of.

The first launch of the Ariane 44L booster has been delayed for
at least another week, while Arianespace technicians and
engineers determine the source of a liquid hydrogen leak in the
third stage engine.  The launch which was originally scheduled
for May 26, but was delayed for a day when problems were
discovered between ground communications and the booster.  It was
postponed again last Saturday when a leak was discovered in the
third stage engine.  The booster will carry the Superbird A and
DFS Kopernikus 1 telecommunications satellites.

As of Friday, June 2 the Magellan Venus Radar Mapping spacecraft
is about 3,735,101 miles from earth traveling 60,293 miles per
hour relative to the Sun.  The spacecraft is operating normally
following the long holiday weekend.

Stephania Follini, the woman who spent a record 130 days isolated
in a cave, was undergoing tests last week to determine the
philological effects of her long term isolation experiment.
Despite the fact that she's lost 17 pounds, she's reported to be
in good health, and at this point all test results have been
normal.

This has been Jordan Katz reporting for the National Space
Society's Space Hotline for the week ending June 4, 1989.  This
message will next be updated on June 11, 1989.

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

End of SPACE Digest V9 #478
*******************