Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_3/V13_307.TXT

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Subject: SPACE Digest V13 #307

SPACE Digest                                     Volume 13 : Issue 307

Today's Topics:
              Voyager Update - 03/21/91
          NASA Headline News - 03/21/91 (Forwarded)
              Re: Space Profits
               Re: He3 on Moon?
          MAJOR SOLAR FLARE ALERT - 20 MARCH
                 Vacuum tubes

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: 22 Mar 91 07:28:01 GMT
From: zaphod.mps.ohio-state.edu!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Voyager Update - 03/21/91


                           VOYAGER STATUS REPORT
                              March 21, 1991

                                Voyager 1

     The Voyager 1 spacecraft collected routine science and engineering
data during the past week.  UVS (Ultraviolet Spectrometer) data was collected
from sources WD 1629+782 and SS Cygni.  On March 12, one frame of high-rate
PWS (Plasma Wave) data was recorded.

     On March 13, a Dummy CC was transmitted to the spacecraft to reset the
Command Loss Timer; the command was received by the spacecraft.  Also on
March 13, the Voyager Project requested that the DSN (Deep Space Network)
terminate the 34 meter Canberra track (4 hours 50 minutes) early for an
arrayed antenna emergency support for Voyager 2.  A TLC (Tracking Loop
Capacitor) test was performed on March 14; the results were nominal.

     The Magnetometer instrument on Voyager 2 is reading 0.7 gamma for the
magnetic field strength, and on Voyager 1 the magnetometer instrument is
reading an average of around 1.3 gamma before background subtraction.


                               Voyager 2

     The Voyager 2 spacecraft also collected routine science and engineering
data. UVS data were taken on CH Cygni and BD+28 4211.  Glimpses into the data
indicate the instrument is doing well although there were several periods of
poor quality data on March 8, 10, and 13.

     On March 12, a science calibration for the PLS/MAG/LECP
(Plasma/Magnetometer/Low Energy Charged Particles) instruments was completed
along with one frame of high-rate PWS being recorded.

     On March 13, a quarterly playback of PWS data was scheduled.  DSS 43
(Deep Space Station 43, 34 meter antenna in Canberra) was unable to support
due to a red power supply for the line driver frequency oscillator.  The bay 1
heater was turned off and the X band went to high power in preparation of
going to playback (7.2K).  In an attempt to acquire the signal an array was
made with both 34 meter antennas in Canberra.  The antenna array was brought
on line, but the array output was insufficient.  The playback was not received
and will have to be rescheduled at a later time.

     On March 14, gyroscopes B and C were turned on and the gyro fault test
was enabled.  No gyro swap occurred.  PWS observed unusually strong
interference signals at the turn on of the gyroscopes.  Also on March 14, the
Plasma instrument on Voyager 2 recorded the average solar wind speed of 351
kps, a velocity average of 394 kps and measured a particle density of about
.015 per cm3.


                CONSUMABLE STATUS AS OF 03/21/91

     P R O P E L L A N T    S T A T U S           P O W E R
               Consumption
                 One Week  Propellant Remaining Output Margin
     Spacecraft     (Gm)             (Kg)        Watts  Watts
      Voyager 1       6          36.2 + 2.0       366   55
      Voyager 2       6          39.1 + 2.0       369   47

      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | Change is constant.
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 |
 |_____|/  |_|/       |_____|/                      |

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

Date: 22 Mar 91 07:37:17 GMT
From: mips!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: NASA Headline News - 03/21/91 (Forwarded)



             Headline News
Internal Communications Branch (P-2) NASA Headquarters

  Thursday, March 21, 1991        Audio Service: 202 / 755-1788

This is NASA Headline News for Thursday, March 21, 1991

Preparations at the Kennedy Space Center for the next shuttle mission
are moving right along.  The terminal countdown demonstration test
with Atlantis' flight crew and ground launch control team went
extremely well yesterday.  The Gamma Ray Observatory is
undergoing a shuttle systems interface test today.  KSC's launch
readiness review began today and concludes tomorrow.  Atlantis will
be loaded with its hypergolic fuels over the weekend.  Next Tuesday
and Wednesday, flight management will hold the STS-37 flight
readiness review.

Discovery is scheduled to be rolled to the Vehicle Assembly Building
Monday, March 25.

The STS-40 Spacelab Life Sciences mission is also moving steadily
along toward its planned May launch on Columbia.  Orbiter and
payload technicians plan to install the Spacelab habitable
module into Columbia's payload bay this weekend.

                   * * * * * * * * * * * * * * * *

NASA today submitted a restructured Space Station Freedom
plan to the Congress.  The new plan, which was outlined in a press
briefing by Associate Administrator for Space Flight Bill Lenoir, calls
for assembly of Freedom beginning in mid-1996, with a man-tended
capability in late 1997.  The new plan calls for a four-person,
permanently-manned capability in 2000.  According to Lenoir, the
restructuring includes many changes which will simplify the technical
and operational aspects of the station.  In a letter to the NASA
Congressional committees, Administrator Truly says the new plan will
pave the way for a sustained U.S. leadership role in space
through the next century.

                   * * * * * * * * * * * * * * * *

Magellan and its radar system also continue to perform well.
All of the star calibrations and momentum wheel desaturations
performed recently have been successfully executed.  Magellan began
its 1,260th mapping orbit yesterday.  Ninety-four percent of the data
has been returned to Earth, which represents about 65 percent of the
total Venus surface area.

Jet Propulsion Laboratory flight controllers today are uplinking the
final computer program files which will restore the articulation and
attitude control system (AACS) B-side memory.  This process not
only will restore full redundancy to the AACS memories, but includes
fault detection which will quickly isolate the memory in the event of a
future chip failure.

                   * * * * * * * * * * * * * * * *

Galileo today is executing a trajectory correction maneuver to
help shape its flight path for the asteroid Gaspra encounter on October
29.  Otherwise, the spacecraft continues with routine housekeeping
activities and readouts of data from science instruments.   Currently
Galileo is about 36 million miles from Earth and 110 million miles
from the Sun, traveling at a heliocentric speed of 68,700 miles per
hour.  Round-trip communication time is now 6 minutes, 24 seconds.


Here's the broadcast schedule for Public Affairs events on NASA Select
TV.  All times are Eastern.  NASA Select TV is carried on GE Satcom
F2R, transponder 13, C-Band, 72 degrees W Long., Audio 6.8,
Frequency 3960 MHz.

Thursday, 3/21/91
        1:00 pm        Taped replay of House Subcommittee on VA-HUD &
          Independent Agencies hearing on the recommendations of the
          Committee on the Future of the U.S. Space Program.  Committee
          chairman Norman Augustine and vice chair Laurel Wilkening
          were witnesses.

        4:00 pm        STS-37 landing simulation from Dryden Flight Research
          Facility.

      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | Change is constant.
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 |
 |_____|/  |_|/       |_____|/                      |

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

Date: 20 Mar 91 17:36:32 GMT
From: usc!samsung!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: Space Profits

In article <[e-mail]> [e-mail] (Paul Blase) writes:

[note: he is responding to Nick Szabo's post about standards...]

>I suppose that you've never heard of gasoline, Ethernet, VME bus, Airline
>traffic control procedures, the telephone system, fax machines, or the IBM
>PC? All of these are more-or-less international standards.  Industry WILL
 ...

If the IBM PC is one of your standards, perhaps we're better off
building custom machinery. :-)

Phil Fraering
[e-mail]
And, no, I wasn't writing this post from my TRS-80 Model 4P.

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

Date: 20 Mar 91 19:50:12 GMT
From: [e-mail]  (Scott A Geels)
Subject: Re: He3 on Moon?

The following is a data dump on the 3He energy possibility. If you are still
trying to calculate the Lunar 3He quantity,  I suggest you stop reading. Most
of this data is from a presentation by Gerald L. Kulcinski (Director of the
Fusion Technology Institute,  University of Wisconsin) and from some of my
own research.

The total 3He fluence on the Lunar surface is ~500 million tonnes over the
last 4 billion years. The Lunar He is broken down into 18 ppm 4He and 8.4 ppb
3He in the soil, for a total of 1,042,000 tonnes of 3He to a depth of 0.5
m. These numbers have been verified with Apollo data (available upon request).

One kg of 3He can theoretically produce 10 MW-yr of energy in a D-3He fusion
reaction. This means that 20 tonnes of 3He could supply one U.S.-year of
electricity.

This 3He could be processed in the following way:
1) Mine the regolith and heat the soil to ~700-900 C, releasing the volatile
gases in the soil (H, H2O, N2, CO2, CH4, CO, He ...- some of which could be
used for a lunar base)
2) Cool down to 50 K,  condensing and separating out all volatiles except He
3) Isotope separation to remove 3He from 4He
4) Cool 3He to superfluid cryogen for storage and transfer

Now for some of the problems:
1) To process the 20t of 3He, 2.4 BILLION tonnes of lunar regolith must be
processed per year. This regolith must be heated to ~900 C, which will take
an enormous amount of energy even with a highly efficient process.
2) There must be an extremely large isotope separation plant to remove the
relatively useless and much more abundant 4He. About 42000t of He must be
separated to obtain the 20t of 3He.
3) Superfluid He will be very difficult to store both on the moon and on
the return to Earth trip.
4) D-3He fusion is not feasible at this point in time.

It actually may be more feasible to obtain 3He from the atmospheres of some
of the gas giants, where is is estimated that 3He concentration may approach
45 ppm. This would also avoid the many problems with separating He from
regolith.

Scott Geels
Martin Marietta Astronautics Group

Reply to: [e-mail] (or post)

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

Date: Wed, 20 Mar 91 16:58:05 MST
From: [e-mail] (CARY OLER)
Subject: MAJOR SOLAR FLARE ALERT - 20 MARCH
X-St-Vmsmail-To: st%"[e-mail]"

                        --  MAJOR SOLAR FLARE ALERT  --

                                MARCH 19, 1991

                              Flare Event Summary
                          Potential Impact Assessment


                                    --------



MAJOR ENERGETIC EVENT SUMMARY

     Region 6555 spawned a major class M7.0/1F flare at 06:16 UT on 20
March.  The event began at 05:26 UT, peaked at 06:16 UT and ended at 06:18
UT on 20 March.  The event occurred at a location of S25E50.  There were no
radio signatures observed with this event.  No sweeps were observed either.

     Region 6555 appears quite formidable in white and H-alpha light.  It
is an impressive region to see, and contains a very large penumbral area
with large spots encompassed within the penumbra.


POTENTIAL TERRESTRIAL IMPACT ASSESSMENT

     This major class M7.0/1F flare will not have a terrestrial impact.  It
was radio-quiet and was rather weak as far as major flares go.

     Region 6555 has the potential to produce major flaring.  Minor M-class
flaring will certainly be observed from this region over the coming week,
probably intermixed with occassional isolated major flares.

     Region 6545 has decayed to the point now where major flaring is not
likely to be observed.  Minor M-class flaring could continue, but major
flaring is no longer a real threat from this region.

     A bulletin will be released near 06:00 UT on 21 March to reflect
the decreased flare probabilities and update the warnings.


**  End of Alert  **

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

Date: Thu, 21 Mar 91 14:17:37 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Vacuum tubes


>Date: 19 Mar 91 23:53:04 GMT
>From: agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
>Subject: Re: railguns and electro-magnetic launchers

>>... Has anyone ever attempted to
>>launch a payload out of a EM launcher that is at all complicated, in the
>>sense of having telemetry, etc... ?

>Nobody's done this with an EM launcher.  However, it has been done many
>times with old-fashioned chemical guns, starting with radar proximity
>fuzes in WW2 and progressing to upper-atmosphere research instruments in
>the 1960s with Project HARP.

>(The proximity fuzes were particularly impressive because the electronics
>in them used *vacuum tubes*...)

>"[Some people] positively *wish* to     | Henry Spencer @ U of Toronto Zoology
>believe ill of the modern world."-R.Peto|  [e-mail]  utzoo!henry

I believe most of the modern devices (i.e. the antitank projectiles that are
shot out of cannons, and the bombs that go *through* a concrete wall or floor,
sense the open space beyond, and *then* detonate) are solid state. While it
would be difficult to judge, I suspect that vacuum tube technology is
ultimately more resistant to high-G shocks - solid state systems are dependent
on a fairly brittle crystalline structure, while vacuum tubes just have to
maintain metal elements in a certain configuration with respect to one another.
Of course, these would not be off-the-shelf items... :-)

Vacuum tubes have a lot of other features that make their use in space
attractive.
       John Roberts
       [e-mail]

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

End of SPACE Digest V13 #307
*******************