Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v09_5/v9_552.txt

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Subject: SPACE Digest V9 #552

SPACE Digest                                      Volume 9 : Issue 552

Today's Topics:
            space news from June 26 AW&ST
           Payload Status for 07/14/89 (Forwarded)
              Questions about Apollo 11
                 Re: Moonwalk
            Re: Questions about Apollo 11
         Re: Procurement and future computers
----------------------------------------------------------------------

Date: 24 Jul 89 03:36:56 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from June 26 AW&ST

Asiasat is in trouble -- the Bush administration's embargo on shipment of
high technology to China prevents its Hughes-built satellite from being
launched on Long March next April.  Asiasat is lobbying for an exception.

Partial restoration of Aerospace Plane funds is now likely, although it
is likely that there will be some reduction and some resulting schedule
slip.

Interior Dept.'s Bureau of Land Management is evaluating Geostar for
tracking its aircraft.  BLM aircraft do much flying at low altitudes
in wild areas, and crew safety is a major concern.  Existing schemes
involving frequent manual position reporting are very cumbersome.
Six aircraft and two helicopters have been equipped with Geostar hardware
for a two-year trial, and so far it is working very well.

Locstar [I think this is the European side of Geostar] chooses Matra to
build two satellites for European location and messaging services.

Insat, the Indian comsat scheduled for launch June 29, is badly damaged
when a 75-lb hoist hook falls 30 ft onto it.  Although the satellite
was loaded with fuel, there was no explosion and nobody was hurt.  The
USAF, India, and McDonnell Douglas (the launch contractor) are assessing
the damage, but several months of repairs will probably be needed and it
is possible that the satellite may be a writeoff.  The launcher will
probably be used for the British BSB broadcast satellite, which is also
in line for a Delta launch.

Ariane 5 development program will probably slip several months and perhaps
longer, because a US-built solid-fuel-mixing machine destined for Kourou
is being diverted to US solid-rocket manufacturer Hercules to replace a
mixer damaged in an accident early this year.  The mixer was to reach
Kourou in early fall to be incorporated into the Ariane 5 SRB manufacturing
plant, along with another mixer to arrive late in the year.  Worse, the
second mixer may be delayed because the first one needs to be reworked to
fit Hercules's needs, and manpower is short.  The Europeans are Not Pleased,
and are urging the US to deliver the mixers as originally scheduled, saying
that Hercules has others.  "This could go down as another black day in
European-US space relations, and it comes at a time when Europe already
is questioning the reliability of the US as a partner..."

Story on NASA Lewis work on slush hydrogen as fuel for the Aerospace Plane.
Slush is the prime candidate for NASP fuel, as it is both denser than
liquid hydrogen and a better coolant.  Work so far indicates that there
are no impossible roadblocks, just a lot of technology development needed.
Major problems are efficient production of slush, measurement of solid-
liquid ratio for tank-capacity gauges and fuel-flow meters, and the choice
of tank-pressurization gas (hydrogen will tend to condense out, melting
the slush and interfering with pressurization, while helium is costly and
needs heavy, bulky pressure tanks; a mixed scheme, using a layer of helium
to separate hydrogen gas from the slush, is being investigated).

William Lenoir, ex-astronaut now in charge of the space station, urges
accelerating start of station assembly to get things moving.  The idea
has not yet been studied in depth.  Lenoir says the station is likely
to shrink a bit if funding continues tight, and he's not sure that the
20 shuttle flights allotted to station construction are enough, but
identifying such problems and sorting them out is currently his first
priority.  He says the idea of switching to solar-dynamic power has
been rejected:  the technology has not been as thoroughly proven as
he'd like, there was a distinct risk of schedule slips, and it would
cost more in a time of tight funding.  It is still an option for a later
upgrade.

Senate authorizing committee gives NASA full funding for CRAF and Cassini,
on condition that NASA establish a firm cost-control plan, to include
cancellation of CRAF if cost limits are exceeded.

NASA astronaut David Griggs, scheduled to fly a shuttle mission late this
year [not sure which one], dies in a flying accident in Arkansas.

Photo of a model of a Tupolev proposal for a hypersonic transport, on
show at the Paris air show.  [Interestingly enough, the aft fuselage has
a flat top with no central fin -- meant to carry a spaceplane on top??]

Pratt&Whitney propulsion people working on the Aerospace Plane say that
most everyone agrees that some rocket propulsion will be needed for the
final boost into orbit, and that all three airframe contractors include
one in their designs.

General Dynamics starts preparing an Atlas-Centaur for launch from the
Cape, carrying a Navy comsat.  This will be the last expendable launch
under NASA authority.  The satellite is the one that was scheduled to
go up two years ago when the Centaur's hydrogen tank was destroyed in
a pad accident.

NASA prepares for antinuclear protestors to object to the Galileo launch
carrying isotope power units.  The "Florida Coalition for Peace and
Justice" is claiming "...it only takes one Challenger-type explosion
and launch or one Chernobyl accident in space to destroy life on our
fragile planet...", and that solar power would be a practical substitute.
(Both false -- such isotope generators have reentered and disintegrated
before without significant ill effect, and solar power is unworkable for
outer-solar-system missions, especially in Jupiter's high-radiation
environment.)  A more moderate group, the "Committee to Bridge the Gap",
although it opposes space nuclear power in general and believes there
are some risks in the Galileo launch, has given Galileo its blessing on
the grounds that the benefits outweigh the minor risks.  NASA says the
worst case would be a reentry during one of Galileo's Earth flybys; this
would be more likely to disperse the plutonium-238 in the isotope packs
than a launch accident.  The CtBtG expresses some doubts about the numbers
in the safety assessments, although it says NASA has done a good job on
the test program for the generators.  The White House must approve the
launch of the generators before Galileo can go up.

Voyager discovers a large dark spot on Neptune, which (on reexamination
of older pictures) has been there since at least January.  The spot is
comparable to Jupiter's Great Red Spot, in proportion to the planet.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 15 Jul 89 06:34:28 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Payload Status for 07/14/89 (Forwarded)


                                     Payload Status Report
                                     Kennedy Space Center
                                     Friday, July 14, 1989


          George H. Diller

          Galileo/IUS-19

               Final prelaunch assembly of the Galileo spacecraft continues
          in the SAEF-2 planetary spacecraft checkout facility.  The low
          gain antenna has been installed and checked out.  Final thermal
          blanket installation continues and is scheduled for completion at
          the end of this week.  The installation of micrometeorite
          shielding is also nearing completion.

               The sun gate, acquisition sensor, and star scanner have been
          installed and testing on those instruments is finished.  Testing
          has also been completed on the attitude control sensors.  The
          magnetometer has been installed, connected, and calibrated.
          Deployment tests of the science boom and the pair of RTG booms is
          complete.

               A decision has been made to reschedule the installation of
          the radio relay antenna to later at the Vertical Processing
          Facility.  Some additional thermal blanket work is necessary in
          the area of the antenna.  This system is used by the Galileo
          orbiter to receive data from the probe after its deployment.

               Earlier this week a test was performed between Galileo and
          the MILA tracking station at KSC.  The exercise attempted to
          determine whether the power and the pair of radio frequencies
          used by MILA could cause spurious commands to be introduced into
          the spacecraft computer.  Such a concern arose on Magellan during
          the launch countdown.  While a low level of radio noise in the
          spacecraft receiver was detected, the test determined that
          inadvertant commands to Galileo's computer is unlikely.

               Checkout of the Inertial Upper Stage booster continues on
          Cape Canaveral Air Force Station.  The first and second stage
          have been mated, and this week the booster was attached to the
          aft airborne support equipment.  Electrical testing is now
          underway.  Mating with the forward ASE is scheduled for Monday
          and will also be followed by a series of electrical tests.  The
          IUS will be moved to the Vertical Processing Facility on July 23
          and Galileo's arrival will follow on July 24.  Preparations will
          then begin for IUS/Galileo mating.


          SSBUV

               Shuttle Solar Backscatter Ultraviolet experiment (SSBUV)
          will provide direct in-orbit data for calibration of ultraviolet
          readings provided by NOAA-9, NOAA 11, and the Ultraviolet
          Atmospheric Research Satellite.  Its primary use relates to the
          long term studies of atmospheric ozone depletion.  This will be
          the first of ten flights for the instrument scheduled between now
          and the end of 1995.

               The payload consists of two GAS-type canisters which are
          mounted on an adapter beam in the orbiter.  One canister contains
          the instrument and operates with a motorized door assembly while
          the other canister contains the support systems.

               SSBUV is currently in Hangar AE on Cape Canaveral Air Force
          Station and is ready to be transported to the orbiter processing
          facility.  On Tuesday, July 18, it is scheduled to be mounted on
          the right payload bay wall of Atlantis.  On Wednesday, July 19,
          an interface verification test (IVT) will be conducted.




          AC-68/FltSatCom F-8

               Checkout of the Atlas Centaur on Pad B at Launch Complex 36
          is going well.  Testing of the Atlas stage and Centaur stage
          propulsion systems is underway.  The installation of the vernier
          engine thrusters used in launch vehicle guidance has been
          completed.

               The nose fairing has been moved to the ESA-60 explosive safe
          area where it will be prepared for its eventual encapsulation of
          the FltSatCom satellite late in August.  The spacecraft remains
          scheduled to arrive at Cape Canaveral Air Force Station on July
          31 and will be taken to the Hangar AM spacecraft checkout
          facility for final assembly and testing.

               Ground facilities and ground support equipment continues
          under test at the launch pad and in the Complex 36 blockhouse.
          There have been no signifcant problems.

               The Terminal Countdown Demonstration test - a practice
          countdown, propellant tanking, and launch team certification - is
          scheduled for August 9.

               The launch of AC-68 remains targeted for September 8.

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

Date: 14 Jul 89 20:11:43 GMT
From: dsacg1!bcd-dyn![e-mail]  (dbp)
Subject: Questions about Apollo 11



I watched the CBS special about Apollo 11 last night.
(Thanks to whoever posted the notice; I wouldn't have known
about it otherwise.)  Can anybody answer two questions?

There is lots of footage looking backward as a stage separates and
falls away.  The cameras that took these shots were mounted in other
stages that were eventually discarded as well.  How were the pictures
from those cameras retrieved?  Was there a downlink so the separation
could be monitored in Houston as it happened?  Was it recorded in
the CM and seen only after splashdown?

This one I've wondered about for 20 years.  There is the famous view
of the moon's surface as the Eagle was landing.  I suppose the
pictures were looking out through the LEM's window.  Just at landing,
something that looks like a hand holding a needle-like object appears in
the upper right-hand side of the picture and comes down across the window.
What was that?  What did it do?

Doug Pape    (dbp@bcd-dyn!dsacg)
Battelle Memorial Institute
Columbus, Ohio
614 424-5667

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

Date: 16 Jul 89 12:31:02 GMT
From: cwjcc!mailrus!shogun![e-mail]  (Marc Siskin)
Subject: Re: Moonwalk

In article <[e-mail]> [e-mail] (Doug Krause) writes:
>
>Also, how did the camera that was left behind on the Moon track the
>top of the Eagle taking off?  and how did they get THAT reel of film
>back?
>
>Douglas Krause                     CA Prop i:  Ban Gummie Bears(tm)!
>--------------------------------------------------------------------
>University of California, Irvine   ARPANET: [e-mail]
>Welcome to Irvine, Yuppieland USA  BITNET: DJKrause@ucivmsa

I am not sure how long the Apollo astronauts were on the moon, but I do
know that teh shot of the LM launching was not from Apollo 11 but from a
later flight.  It wasn't filmed either but was a live video shot from the
Lunar Rover's camera.  It was exciting watching the liftoff live (so to
speak) when it occured.

Marc Siskin  Child of the Space Age
Any opinions expressed are my own.  The University of Michigan doesn't pay me
enough to have opinions for them.

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

Date: 17 Jul 89 18:09:21 GMT
From: att!mtuxo!mtgzz!drutx!druhi![e-mail]  (Tim Larison)
Subject: Re: Questions about Apollo 11

In article <[e-mail]>, [e-mail] (dbp) writes:
>
>
> I watched the CBS special about Apollo 11 last night.
> (Thanks to whoever posted the notice; I wouldn't have known
> about it otherwise.)  Can anybody answer two questions?
>
> (first question deleted)
>
> This one I've wondered about for 20 years.  There is the famous view
> of the moon's surface as the Eagle was landing.  I suppose the
> pictures were looking out through the LEM's window.  Just at landing,
> something that looks like a hand holding a needle-like object appears in
> the upper right-hand side of the picture and comes down across the window.
> What was that?  What did it do?
>

I believe that is the shadow of the antenna on top of the LEM on
the lunar surface.  The needle like object is the antenna, and the
"hand" is the base of the antenna.

I found the CBS special very good, though they did take dramatic license
in one case.  When the top of the LEM blasted off from the moon, they
showed a television feed of the LEM leaving the lunar surface.
As I remember, there were no live shots of this on Apollo 11;  only
on a later Apollo moon landing did they leave a tv camera behind to
record the takeoff from the lunar surface.  But CBS took that footage
and made it appear that we were watching Apollo 11 take off.

                Tim Larison  att!druhi!tml

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

Date: 6 Jul 89 17:58:46 GMT
From: cs.utexas.edu!wasatch!uplherc!esunix![e-mail]  (Bob Pendleton)
Subject: Re: Procurement and future computers

From article <[e-mail]>, by [e-mail] (John Roberts):
>
>>From: [e-mail]
>>If you want a sophisticated machine for 1998, and you REALLY MUST roll
>>your own, then do something real instead of spending many millions for
>>a museum piece. I'd suggest you look at:
>
>>    - minimum resolution on screen of 300 dpi (400 would be nicer)
>>      with ~32 bits per pixel to handle color, intensity and
>>      transparency.
> How would you allocate the bit fields? Many display designers regard 24 bits
> (8 each of RGB) as being fully satisfactory for both color and intensity.
> Does "transparency" in this context mean priority of overlapping objects or
> frames?

The extra 8 bits can be used for a number of different things. Overlay
planes, for things like menus and cursors, underlay planes, for
backgrounds, window priority, how you interpret the rest of the bits
in the pixel... 8 bits really isn't enough. I'd like 16 bits just for
window IDs.

Anyway, for many applications 24 bits of color just isn't good enough
9 bits of RGB is needed. For a true 3D display you also need something
like a z buffer. 16 bits of z isn't always "good enough."  I've met
people who will not be happy until they can get a 32 bit floating
point z buffer. And of course, if you want stereo you need double
buffering.

Lets see, that's 27 bits of color, times 2 for stereo, plus 16 for
window bits plus 24 for z is 94 bits per pixel. It doesn't look that
hard to come up with a frame buffer design that uses more than 100
bits per pixel.

A 24 bit true color frame buffer might impress computer people, like
me. But it doesn't cut it with artists. Or with scientist who are
trying to simulate reality.

            Bob P.
--
-              Bob Pendleton, speaking only for myself.
- UUCP Address:  decwrl!esunix!bpendlet or utah-cs!esunix!bpendlet
-
-             Reality is stranger than most can imagine.

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

End of SPACE Digest V9 #552
*******************