Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_4/V12_460.TXT

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Subject: SPACE Digest V12 #460

SPACE Digest                                     Volume 12 : Issue 460

Today's Topics:
             space news from Aug 27 AW&ST
         Re: Motorola Cellular phone Comsats
        Re: Man-rated SRBs (was Re: Junk the shuttle?)
              Re: Teleoperations
                Jobs In Space
           Re: disposal of N-waste into sun
          Re: Psych. effects of moonwalking
               Antartic Ozone depletion
              Magellan Update - 10/15/90

Administrivia:

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

Date: 15 Oct 90 04:23:00 GMT
From: snorkelwacker!usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from Aug 27 AW&ST

ISAS discloses that the Astro-C, aka Ginga, X-ray astronomy satellite is
losing altitude more quickly than expected, and has been since around
the start of the year.  Intense solar activity is blamed.  At this rate
it will reenter within a year.  It was launched in 1987 for a nominally
one-year mission, but is still active.

NHK (Japan Broadcasting Corp) decides to launch its BS-3A tvsat without
insurance.  Launch is set for late August on an H-1.  Reasons for the
decision were undisclosed, but satellite insurance is expensive and NHK
has been criticized lately for financial losses.

NRC panel report says that the second phase of EOS should use several
smaller spacecraft instead of one large platform.  The first-phase platform
really does benefit from having all its instruments studying the same area
from the same angle at the same time, the panel says, but similar arguments
offered for the second one have little merit.

Space station makes progress, now only 7% overweight and 8% overpower, but
the ranking Republican (Bill Green) on the relevant House Appropriations
subcommittee has come out against the entire project, increasing House
opposition.

First AW&ST report of Magellan's silent periods.  [As usual, I will skip
detailed coverage because it's old news and was covered well here at the
time.]  However, the first radar pictures, taken before the troubles,
look very good.  Spacecraft now in safe mode pending troubleshooting.

Speaking of safe modes, Hubble safed itself again Aug 19, for no obvious
reason.  This may be an occasional side effect of the way the solar arrays
flap when going from darkness to sunlight; corrective software is in the
works for that.

Columbia hydrogen leaks tentatively attributed to tiny glass beads causing
scratches on metal surfaces in the tank-attach fitting.  The beads were
found after cleaning of the fitting.  Such beads are used in polishing and
similar work, and parts of the plant that made the fittings use them.

Soviets plan extensive EVA on Mir to move solar arrays from Kristall to
Kvant 1, minimizing shadowing of arrays by each other, and to repair the
damaged hatch.  Internal wiring work will also be done for the solar-array
move.  Two EVAs will be done late this year, one for the hatch and one
for preparations for the array move (assuming the first fixes the hatch).
The actual move will occur early next year.  Progress M-4, which docked
to Mir Aug 17, carried parts for the wiring work.

Progress M-4 is expected to be undocked in late Sept, and will do maneuvers
simulating those that will be used for the cargo-return capsule option of
Progress M.  M-6 will be the first actual use of the capsule, late this year.

Soviets say they now have adequate data on free-fall effects for periods
of up to a year, and do not immediately plan any more very long stays.
Mir crews will be up a mere six months each for the next couple of years.
[For those who aren't aware of it, the US record is three months.]  Mir
crews in the near future will include a lot of guest cosmonauts, who will
go up with a new crew and back down with the old one.  This December the
Japanese TV reporter will fly.  Next summer's crew has the British Juno
cosmonaut pencilled in, despite Juno's funding problems.  The late-1991
crew will have the Austrian cosmonaut, and the mid-1992 crew the next
French cosmonaut.  All are paying customers.

Soviets consider adding a new thruster package on an arm attached to
Kvant 1.  Mir could use better roll control now that heavy add-on modules
are sticking out in two directions, with two more planned for late next
year.

Soviets use slightly modified pre-reentry procedures for Soyuz TM-9,
separating both the forward orbital module and the aft service module
simultaneously after retrofire.  Simultaneous separation was used on
early Soyuzes, and the return to it was aimed at avoiding any possible
problem with the Soyuz's damaged thermal blankets.  The cosmonauts
report that the capsule handled perfectly on reentry.

Long story on Japan's first shuttle astronaut, Mamoru Mark Mohri, now in
training for the Spacelab J mission late next year.  Two more Japanese
shuttle astronauts are set to fly on International Microgravity Lab
missions in 1993 and 1995.  NASDA values these missions particularly for
the flight experience they will contribute to design of the Japanese
space-station module.  The Japanese astronauts say they already have
one problem to report with the Spacelab J hardware:  it is too heavily
automated, leaving little possibility of manual troubleshooting in case
of difficulties.  "All we can do is shut it down."  They also say that
NASA's post-Challenger safety-documentation requirements are excessive
and are interfering with mission planning.  [Lots more details on the
experiments to be flown.]

Details of ISAS's next two major scientific satellites:  Solar A, for
launch late next year, with the first solar imaging equipment to beat
the capabilities of Skylab's solar telescope [from 1973], and Geotail,
a solar-wind probe with very long antennas, a joint ISAS-NASA project
for launch on Delta in mid-1992.  [Details on experiments.]

Descriptions of the Japan's next two astronomy satellites, Astro-D (1993)
and Muses-B (1995).  Astro-D will carry an X-ray telescope with much
better sensitivity and spectral resolution than existing ones.  Muses-B
will be a radio observatory for VLBI work together with ground-based
receivers.  Both will be launched from Kagoshima, Astro-D on the last
M-3S-2 and Muses-B on the first M-5.  Both missions are international
collaborations, with NASA supplying the X-ray telescope for Astro-D and
various nations planning radio observations in conjunction with Muses-B.
Both also present design challenges, with Astro-D's telescope having to
telescope [!] to fit under the M-3S-2 payload fairing, and Muses-B's
10m dish presenting problems in both antenna deployment and precise
attitude control of a flexible spacecraft.

Story on Japanese studies, both government and commercial, for autonomous
space stations, lunar bases, and advanced concepts for both launch and
in-space propulsion.  One project of note is work on electric propulsion
for deep-space missions, notably the Jupiter probes specifically mentioned
in Japan's new government space policy.
--
"...the i860 is a wonderful source     | Henry Spencer at U of Toronto Zoology
of thesis topics."    --Preston Briggs |  [e-mail]   utzoo!henry

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

Date: 15 Oct 90 13:30:52 GMT
From: mcsun!ukc!inmos![e-mail]  (Conor O'Neill)
Subject: Re: Motorola Cellular phone Comsats

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <1050400039@cdp> [e-mail] writes:
>>Aren't the Motorola sats going to be launched by Pegasus?
>
>The original plan was that the initial constellation would be launched
>in clumps by Delta or Atlas, with Pegasus used to launch individual
>replacement satellites.  I'm sure the Pegasus consortium is bidding real
>hard to get them all going up on Pegasus, since it would be a wonderful
>way to get mass production going, but whether Motorola et al will buy
>that is another question.

When I first heard of this "project", I assumed that it was another of
the hundreds of projects which are proposed by somebody, hyped for a while,
then quietly die. From what Henry says, this one actually seems more
concrete than most.

All I know is that they propose to provide world-wide cellular-phone-type
communications, using a series of 70 or so low orbit satellites.
Could anyone in the know (preferably from Motorola) please give a better
run-down on the details.



---
Conor O'Neill, Software Group, INMOS Ltd., UK.
UK: [e-mail]        US: [e-mail]
"It's state-of-the-art" "But it doesn't work!" "That is the state-of-the-art".

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

Date: 15 Oct 90 14:37:27 GMT
From: usc!wuarchive!emory!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: Man-rated SRBs (was Re: Junk the shuttle?)

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Mike McManus) writes:
>>... What is the problem with SRBs?  Safety?
>>Reliability?  How do these issues compare against liquid fueled engines?
>
>Just about the only things *right* about them are that they have high
>thrust for their size, and they are a bit cheaper to develop than
>liquids.  Guess what the clincher was for the shuttle?

There are also a lot less things to go wrong in solids. There are no
turbo pumps, no complex valves and plumbing, no cryogenic liquids to
handle, no complex electronic control system to fail, just light and
go. Admittedly the shuttle's SRBs are poorly designed, but in general,
solids are the most reliable rockets we know how to build.

Gary

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

Date: 15 Oct 90 14:57:22 GMT
From: sdd.hp.com!wuarchive!emory!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: Teleoperations

In article <[e-mail]> [e-mail] (Austin) writes:
>
>    Holes in the ground don't just appear magically. Robots don't tip over
>because Merlin dreams in his Ice Cave. Arguements of this type are specious at
>best, but usually end up sounding like mystic warnings of unforseeable,
>unexplainable occurrences, which really have no place in a technological
>discussion.

As anyone who has ever left the paved sidewalks and manicured lawns of
academia can tell you, a perfectly solid looking rock can turn under
your foot and dump you on your butt if you don't react very quickly.
With a 30 minute time lag you won't even know your robot fell until
long after the event. If you limit your robot's movements to perfectly
understood terrain, you aren't exploring. I have even fallen on a well
used path on my farm when a rock that I had stepped on every day for
years unexpectedly turned under my weight. No amount of computer simulation
could have predicted that fall or allowed me to make corrections for it
30 minutes in advance.

Gary

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

Date: 15 Oct 90 21:44:00 GMT
From: ux1.cso.uiuc.edu!ux1.cso.uiuc.edu!uxa.cso.uiuc.edu![e-mail]
Subject: Jobs In Space


Looking for information concerning _any_ summer '91 employment opportunities for
Undergraduate Aerospace students.  I will be considering just about any oppor-
tunity (yes, I can see myself in Antartica).

Any help will be greatly appreciated.

Snail mail to:    Garret Gengler
                  202 E. Peabody URH 339 Scott
                  Champaign, IL 61820
---------------------------------------------------------------------------
|  Garret Gengler     | I'll get there (Caaan't get theeere from heeere!) |
|  [e-mail] | - another way. (Caaan't get theeere from heeere!) |
|---------------------| I'll get there another way. (Can't get ... !!!!)  |
|  Let's go Penguins! |              --- R.E.M.                           |
|-------------------------------------------------------------------------|
| University of Illinois           |    (Though I'm no rocket scientist)  |
| Dept. of Aerospace Engineering   |     Mario Lemieux - get well soon!   |
---------------------------------------------------------------------------

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

Date: 15 Oct 90 08:39:58 GMT
From: eru!hagbard!sunic!mcsun!ukc!reading!minster![e-mail]
Subject: Re: disposal of N-waste into sun

In article <[e-mail]> [e-mail] (Alan Hepburn) writes:
>In article <[e-mail]> [e-mail] writes:
>>
>>Do the arithmetic on dissolving the "high grade" waste in a suitable
>>solvent and then dispersing it over a few square miles of ocean.  I
>>think you will find it disappears into the background.  It is high
>>grade only because the ecohysterics have insisted on concentrating
>>it into minimum volume.
>>
>>dan herrick
>
>
>Picture this:  a supertanker modified slightly so that the nuclear
>waste starts out in the bow tank, being diluted 100:1 with sea water.
>This mix is then pumped to the next tank where it is diluted 100:1 with
>sea water.  And so on till the last tank, which is pumped into the open
>ocean.  You would be unable to detect other than background radiation
>in the resulting water.
>

What!!! Diluting nuclear waste doesn't make it disappear as you suggest
above...it merely spreads it out. I have serious doubts to the accuracy
of your last comment - only in mathematics can you say A + delta A
approximates A.

George Bolt.

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

Date: 15 Oct 90 15:41:33 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Re: Psych. effects of moonwalking

From article <[e-mail]>, by [e-mail] (NAME "Chris Welch"):

> Perhaps someone out there has the hard information to settle a little dispute
> for me. A friend has asserted that "All the astronauts who walked on the Moon
> either became intensely religious, alcoholic, or both".
"Intensely religious" is a little arbitrary but the 2 obvious examples are Jim
Irwin (founded High Flight evangelical organisation), and to a lesser extent
Charlie Duke (Born again Christian). I'm basing this on book "For All
Mankind", which seems more useful for this sort of thing than technical
stuff ... :-).

Only one who I ever saw reported to have had alcohol problems was Buzz
Aldrin, these are now behind him.

> I have heard this asserted before and have always dismissed it as being an
> urban myth. I know that one or two astronauts may have been affected to a
> certain extent, but that's all.
Seems you are right.

> (Interestingly enough, when the selection for the UK Juno mission was being
> done the candidates were actually screened to see if they expected to get
> 'cosmic/religous perspective' on the trip. Any who showed a tendency in this
> direction were scrubbed.)
Tells us more about those in charge of Juno than about the profound spiritual
impact of spaceflight, I'd have thought. This impact, irrespective of
religious beliefs, is described by just about *all* astronauts/cosmonauts.

Nick
--
Dr. Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: [e-mail]   BITNET: [e-mail]

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

Date: Mon, 15 Oct 90 18:14 CST
From: [e-mail]
Subject: Antartic Ozone depletion
X-Envelope-To: [e-mail]

In response to message forwarded by (Peter E. Yee)...

>     Preliminary data indicate that depletion of stratospheric
>ozone over Antarctica is matching levels observed in 1987 and
>1989, the lowest ozone years recorded, NASA scientists said.

In a serious vein, does the ozone depletion over the Antartic
continent ever become so great that some degree of ultraviolet
spectroscopy or other research becomes possible?

At what concentration of ozone does the atmosphere become opaque
to ultraviolet wavelengths?


Robert Brown
[e-mail]

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

Date: 16 Oct 90 03:56:26 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Magellan Update - 10/15/90


                          Magellan Mission Status
                            October 15, 1990

     At 9:46AM (PDT) this morining, the Magellan spacecraft started it 222nd
mapping orbit.  Good radar data has been received from all but 4 orbits.
All spacecraft systems are performing nominally.  20 of 22 star calibrations
performed over the weekend were successful, with attitude updates ranging
from .003 degrees to .29 degrees.  One star calibration was partially
successful, and one failed due to a star rejection.  All desaturations were
nominal.

     The angle between the Sun, Earth and Magellan is down to 4.6 degrees.
The predicted limit of the S-Band communications through the High Gain Antenna
is 3.4 degrees, which is expected to be reached on October 20.

     Commands to correct the solar array drive drift has been sent to
the spacecraft on October 12, but the drift problem has continued.  The cause
is being investigated.

     Radar systems continue to perform normally.  32 standard image swaths
were processed by the SAR (Synthetic Aperture Radar) processor, bring to
60 the total number of image swaths processed.  The double exposure artifact
in the orbit 391 image was found to be a minor fixable flaw in the
Experiment Data Record.

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

End of SPACE Digest V12 #460
*******************