Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v13_2/v13_280.txt

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Subject: SPACE Digest V13 #280

SPACE Digest                                     Volume 13 : Issue 280

Today's Topics:
               * SpaceNews  11-Mar-91 *
Re: German conference highlights doubts about ESA's manned space plans
               Re: Reliability
  First Liquid-Fueled Rocket Launching by Goddard - 65th Anniversary
              Galileo Update - 03/14/91
                 He3 on Moon?

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

Date: 11 Mar 91 03:56:19 GMT
From: ka2qhd![e-mail]  (John Magliacane)
Subject: * SpaceNews  11-Mar-91 *


SB SPACE @ AMSAT < KD2BD $SPC0311
* SpaceNews  11-Mar-91 *

Bulletin ID: $SPC0311


                              =========
                              SpaceNews
                              =========

                         MONDAY MARCH 11, 1991

SpaceNews originates at KD2BD in Wall Township, New Jersey, USA.  It
is published every week and is made available for unlimited distribution.



* VOICES FROM SPACE *
=====================
This past week radio amateurs around the world heard the voice of the recently
launched AO-21.  The voice message, coming from the AO-21 downlink frequency
of 145.983 MHz spoke the following words: "I'm completely operational and my
ciruits are functioning perfectly."  This voice mode is referred to as Mode 8
among the AMSAT-DL and AMSAT-U-ORBITA groups responsible for AO-21's design
and assembly.  At this time it is not known how often Mode 8 will be in
operation on AO-21.  Also, engineering checkout is still ongoing and it could
be some time before the operational schedule for AO-21 is known.  Users
should monitor the downlink of 145.983 MHz to see which mode AO-21 is
currently operating.  As soon as a schedule is available from AMSAT-DL,
it will be published immediately and made available to all amateurs.

OSCAR-21 Frequency Allocations and Modes of Operation:

Linear Transponder Uplink:    435.030 - 435.120 MHz (90 KHz)
Linear Transponder Downlink:  145.880 - 145.970 MHz (inverted)
O/P Power: 12 watts max.
Beacon  : 145.810 MHz, CW telemetry.

Gain of satellite RX/TX antennas: 2.3 dBi each (dipoles)
Input sensitivity:  -125 dBm (435 MHz) for a C/No of 45 dB/Hz

SAT-RX-1:  435.016 MHz +-10 KHz  1200 bps, FSK, NRZIC/Biphase-M (JAS, PACSAT)
SAT-RX-2:  435.155 MHz +-10 KHz  (AFC) 2400 bps, BPSK, Biphase-S
SAT-RX-3a: 435.193 MHz +-10 KHz  (AFC) 4800 bps, RSM, NRZIC/Biphase-M
SAT-RX-3b: 435.193 MHz +-10 KHz  (AFC) 9600 bps, RSM, NRZI (NRZ-S) +Scrambler
SAT-RX-4:  435.041 MHz +-10 KHz  (digital AFC) RX for RTX-DSP experiments

The downlink can be switched to the following operating modes:
Transmit frequency:  145.983 MHz

Mode 1: 1200 bps, BPSK, NRZI (NRZ-S) (like FO-20)
Mode 2:  400 bps, BPSK, Biphase-S (AMSAT mode for OSCAR-13 beacon)
Mode 3: 2400 bps, BPSK, Biphase-S (planned for OSCAR-13)
Mode 4: 4800 bps,  RSM, NRZIC (Biphase-M) (like 4800 bps uplink)
Mode 5: 9600 bps,  RSM, NRZI (NRZ-S) + Scrambler (like 9600 bps uplink)
Mode 6: CW keying (only for special events)
Mode 7: FSK (F1 or F2B), e.g. RTTY, SSTV, FAX, etc. (only for special events)
Mode 8: FM modulated by D/A signals from DSP-RISC processor (e.g. speech)


* U2MIR NEWS *
==============
By: John Shalamskas, KJ9U -- 02 March 1991

A probable first in Amateur Radio was achieved today when 16 two way
FM voice contacts were conducted with the MIR spacecraft by Hawaii "hams"
in a single pass.  Ham operators on Oahu and Maui exchanged greetings
with Musa Maranov, U2MIR, in the orbiting Soviet space station.
From approxinately 7:54 AM to 8:05 AM HST, excited Amateurs passed
their callsigns and names to their counterparts who were streaking by
400 km overhead.  The relatively small number of Amateur Radio
stations in Hawaii and a great deal of pre-pass planning allowed
many participants to make contact in a limited time, using only
modest equipment.

After difficulty had been encountered during early packet contacts,
Joe Weite (KH6GDR) suggested emulating the military/commercial process
of parcelling out time slots in a manner that would make best use of
the geographical location of each ground station.  The first attempt at
using this method for voice contacts has proven to be extremely beneficial.

The [tentative] list of happy operators follows:

WA6EMV +  NH6XW     NH6VT     AH6HU     K6WR      WH6CJO    NH6RY     KA6NEI
KH6GDR    WY0H      KZ0A +    KJ9U      AH6GR +   NH6UY     KH6GPI +  KH6QR

A '+' denotes contacts that I did not hear directly, but were confirmed
by others immediately after the pass. Congratulations!

Musa did not use the expected "list" format, but everyone adjusted quickly.
Even though Musa was waiting for calls instead of calling us,
everyone did their best to remain in sequence.  It worked exceedingly well!
Musa kept up a good rate all through the pass, even contacting a couple of
stations on Maui and Hawaii that weren't aware of the list.  These Amateurs
were also quite courteous, even using remote-controlled stations at
high elevations to monitor Oahu in order to prevent interfering with others.

A discussion was held on the 146.88 MHz repeater after the pass.
The general consensus was that this was a very special event!
The mutual cooperation made it easy to hear and work Musa.
There were also a number of requests for an "official" list of
contacts from U2MIR.  We'll have to wait and see if that will happen.
It's quite likely that it will, if we ask Musa to make it available
on his packet radio Personal Message System (PMS.)

The Soviet cosmonauts aboard MIR have been active on 145.550 MHz,
using either packet radio (a digital communications mode) or
narrow-band FM voice.  Scanner enthusiasts should hear the signals
from MIR easily.  Some hams heard Musa using only handheld radios!

I learned a lot of things from this experiment.  The strongest impression
I am left with, however, was that the people here in Hawaii are among
the nicest in the world!  When the operation could easily have become
a "pileup", everyone restrained the urge to talk, waiting their turn in
a civilized fashion.  Hats off to all who helped make this event so
successful!


* SAREX NEWS *
==============
The Shuttle hardware problems that are forcing a delay of this month's
shuttle mission will NOT delay next month's SAREX mission.  Therefore,
a joint ham-radio contact between the Shuttle and Soviet space station
Mir appears possible.


* TNX RPT! *
============
A special thanks to all those who sent e-mail messages to SpaceNews:

WB3JFS, KB5NFN, KC6HEW, N6WDV, N7PDE

73, de John, KD2BD


/EX
--
John A. Magliacane                 FAX  : [phone]
Electronics Technology Department  AMPR : KD2BD @ NN2Z.NJ.USA.NA
Brookdale Community College        UUCP : ...!rutgers!ka2qhd!kd2bd
Lincroft, NJ  07738  USA           VOICE: [phone] ext 607

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

Date: 11 Mar 91 21:45:08 GMT
From: news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: German conference highlights doubts about ESA's manned space plans

In article <[e-mail]> [e-mail] (Andreas G. Nowatzyk) writes:
>True, but I read the original argument slightly differently: It is possible
>to design Solar Max, etc. for in-orbit repair by robots, which was not done.

Actually, Solar Max is interesting because it *was* designed for in-orbit
repair, albeit by humans rather than robots... but in fact about half the
work the astronauts did on it was on subsystems which were not meant for
in-orbit repair!  This all boils down to trying to anticipate what might
fail, and as I said before, the unexpected is the real killer in these
things.

Some of the Hubble salvage schemes likewise involve in-orbit work on
subsystems that were not meant to be opened up in space; they are being
taken seriously with humans but probably couldn't be with robotics.

The Syncom repair was on things that weren't likely to fail in orbit
because they didn't have to work for any length of time, on a satellite
that wouldn't be repairable in orbit anyway because it would be out of reach.
Well, surprise surprise, the ignition control for the perigee motor *did*
fail, leaving the satellite crippled but within reach.  Ditto for the
upcoming Intelsat salvage mission.

And for both Solar Max and Palapa/Westar, a robotic repair mission would
have been a complete failure unless the hardware was very general-purpose,
because the custom-built grappling gadgetry simply did not work.  For
Solar Max, after some ill-advised initial fumbling, a procedure using
the shuttle arm proved workable, barely.  (I don't know for sure, but I'd
be surprised if it would have been practical with teleoperation delays.)
For P/W, there was a purely-manual backup procedure, which got used.
These experiences had sufficient impact that they didn't even bother with
the gadgetry for the Syncom repair, just let the humans do it.  (Note
that this required muscle, not just dexterity, to take the spin off the
bird by hand [!], and existing dextrous robots often are not muscular.)
--
"But this *is* the simplified version   | Henry Spencer @ U of Toronto Zoology
for the general public."     -S. Harris |  [e-mail]  utzoo!henry

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

Date: 11 Mar 91 22:59:56 GMT
From: news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Reliability

In article <[e-mail]> [e-mail] (John Roberts) writes:
>>peculiar myth within NASA that all possible problems can be anticipated,
>>and you really can be certain that the thing will work before you launch it.
>>The universe keeps trying to tell NASA that this is wrong...
>
>That last statement sounds a little too broad. Just about everything they
>launch is chock full of backup systems, and the unmanned devices have both
>on-board recovery systems and provision for ground-based reconfiguration.

All of which can handle only expected classes of failures, by and large.

On-board recovery systems and provision for reconfiguration are of limited
help if your thrusters explode when fired continuously... and we very nearly
sent Galileo up with thrusters that did exactly that.  (The thruster problem
was discovered only because TVSat 1 used the same thrusters, and it fired
them long and hard in attempts to shake its stuck solar array loose.  Had
Galileo been launched on schedule, it would have been very lucky to reach
Jupiter.  TVSat 1 went up during the post-Challenger hiatus.)

On-board recovery systems and provision for reconfiguration are of limited
use if your solar arrays flap every time you cross from sunlight into
darkness... last I heard the HST people had given up on ever being able
to get full compensation for this, as the onboard systems just don't have
enough crunch.  It would be unfair to also mention the mirror-distortion
actuators that don't have enough muscle to take the spherical aberration
out, so I won't :-).

On-board recovery systems and provision for reconfiguration didn't save
Seasat, or the Viking 1 lander, or the attitude-control system on Solar Max
either.  All of these things deal only with expected classes of problems.
They can still be blind-sided by something unexpected.

>If you're thinking of simpler multiple probes, I think that has both good
>and bad points, and has to be evaluated on the merits of each case...

Simplicity vs. multiple missions is a complex tradeoff.  But putting all
your eggs in one basket is foolish whether that basket is simple *or*
complex, because *failures do happen*.  Complex systems, while often
better equipped to cope with failures, also are more prone to them.
--
"But this *is* the simplified version   | Henry Spencer @ U of Toronto Zoology
for the general public."     -S. Harris |  [e-mail]  utzoo!henry

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

Date: 15 Mar 91 16:38:41 GMT
From: pa.dec.com!shlump.nac.dec.com!advax.enet.dec.com![e-mail]  (Larry Klaes)
Subject: First Liquid-Fueled Rocket Launching by Goddard - 65th Anniversary


        Saturday, March 16, marks the sixty-fifth anniversary of Robert
    Goddard's launching of the world's first liquid-fueled rocket, the
    ancestor of all modern liquid-fueled booster.  The flight took place
    in Auburn, Massachusetts (near Worcester) in 1926 and lasted only 2.5
    seconds, reaching an altitude of 12.3 meters (41 feet) and landing
    (crashing, actually) 55.2 meters (184 feet) from the launch site in
    his Aunt Effie's cabbage patch.  Today the launch area is commemorated
    with a small monument surrounded by a busy street and numerous stores,
    including the Auburn Mall.

         Larry Klaes     [e-mail]
                or  ...!decwrl!advax.enet.dec.com!klaes
                or  [e-mail]
                or  [e-mail]

              "All the Universe, or nothing!" - H. G. Wells

         EJASA Editor, Astronomical Society of the Atlantic

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

Date: 15 Mar 91 03:09:20 GMT
From: csusac!csuchico.edu!petunia!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 03/14/91


                            GALILEO STATUS REPORT
                               March 14, 1991

     As of noon (PST) Thursday, March 14, 1991, the Galileo spacecraft is
35,365,790 miles from the Earth and traveling at a heliocentric speed of
70,450 miles per hour; distance to the Sun is 106,360,700 miles (1.15 AU).
Round trip light time is 6 minutes, 20 seconds.

     A NO-OP command was successfully sent on March 11 to reset the Command
Loss Timer to 240 hours, its planned value for this mission phase.

     Commands were sent on March 8 to change the engineering telemetry map
back to a measurement configuration providing greater system visibility into
the AC/DC bus imbalance anomaly.  Earlier, the telemetry map was altered to
accommodate last weeks radio frequency receiver and command detector unit
characterization tests.

     Another RPM (Retro Propulsion Module) 10-Newton thruster maintenance
flushing activity was performed on March 8.  All twelve thrusters were
cleared, except for the P-thrusters, which are used to perform periodic sun
pointing activities.  The spacecraft performance during this operation was
normal and thruster temperatures were similar to those observed on previous
activities.

     Cruise Science Memory Readouts (MROs) were successfully performed for the
EUV (Extreme Ultraviolet Spectrometer), MAG (Magnetometer) and DDS (Dust
Detector) instruments on March 11; another MAG MRO was also performed on
March 8.

     The second of seven planned UVS (Ultraviolet Spectrometer) Lyman Alpha
data collection activities was completed on March 11.

     Another USO (Ultra Stable Oscillator) calibration test was completed on
March 14.  This test is periodically performed providing trend information
characterizing this downlink frequency source.

     The AC/DC bus imbalance measurements exhibited little activity.  The AC
imbalance reading fluctuated 2 DN and now reads 45.2 volts; the DC measurement
changed 6 DN and now reads near 10 volts.  All other power-related telemetry
and subsystem telemetry are normal.  A second AC/DC bus imbalance special
technical review is scheduled to be held at JPL on March 27.  The Review
Board, as before, will consist of personnel from JPL, other NASA centers and
selected members of the standing Galileo Project Review Board.

     The German Space Operations Center (GSOC) has reported completion of
internal Ground Data System (GDS) testing of support capabilities which will be
used to support Galileo Cruise Science Operations starting in September.  No
major liens were identified in quick look post test discussions with JPL.  A
final written test report is expected from GSOC in the near future.  JPL System
Engineers have begun the validation of interface and data products as part of
joint (JPL and GSOC) GDS testing.  Joint testing and analysis of results is
currently scheduled to be completed by mid-April.

     The TCM-9B (Trajectory Correction Maneuver 9B) design implementation was
approved by the Project on March 12, 1991.  The maneuver will be performed on
March 20 using the axial (Z) and lateral (L) thrusters to impart a delta
velocity of about 2.28 meters/sec.  The maneuver sequence final approval
meeting is scheduled for March 18 with sequence uplinked to the spacecraft on
March 19.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | Change is constant.
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 |
 |_____|/  |_|/       |_____|/                      |

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

Date: 14 Mar 91 02:43:57 GMT
From: swrinde!zaphod.mps.ohio-state.edu!wuarchive!rex!uflorida!mailer.cc.fsu.edu!geomag![e-mail]  (Joe Cain)
Subject: He3 on Moon?

Does anyone know the origin of the weird sounding article that just
appeared in the March 15 "Washington Spectator?"
*******************************************************************
.A new "gold rush" is expected on the moon, where large amounts of a
powerful fuel, a hundred times more precious than gold, have been
discovered. "Lunar soil is rich in Helium-3 (He-3) which costs $1,000
a gram," reports <The Machinist>. "Some 100 million tons of He-3 lie
on the lunar surface. A mere 55,000 pounds of He-3 in a fusion reactor
(which scientists expect to build within 15 years) would electrify the
entire U.S. for a year. Nuclear fusion which powers the sun releases
energy by joining atoms together with almost no radioactive waste.
********************************************************************

    The last time I dropped a note to this otherwise political
newspaper about some outlandish scientific sounding article, the
defense was that it was published in some other journal!

I have read that Mercury has a wisp of atmosphere with some He, Na and
O from the solar wind and/or some vaporization of impacting bodies
(maybe a little K), but 3He??? The only gases I have read about in the
lunar regolith involve a little H and He from the solar wind.

Maybe the little green men did it?


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

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

End of SPACE Digest V13 #280
*******************