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[jamsat-news:578] * SpaceNews 30-Jun-97 *

SB NEWS @ AMSAT $SPC0630
* SpaceNews 30-Jun-97 *


BID: $SPC0630


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


              MONDAY JUNE 30, 1997


SpaceNews originates at KD2BD in Wall Township, New Jersey, USA.  It
is published every week and is made available for non-commercial use.


* MIR NEWS *
============
Ham-astronaut and former Mir crew member Jerry Linenger, KC5HBR, told
reporters during an interview on 25-Jun-97 that the crew aboard the
Russian space station has had to "power everything down that's possible,"
including some life-support systems, in the wake of a collision with
an unmanned cargo rocket.  The crash, which damaged a solar array and
punctured one module, resulted in a loss of as much as 50 percent of
the Mir's electrical power.  Speaking at a NASA press briefing, Linenger
characterized the Mir as "darkened ship", and said the crew would operate
"in a slowdown mode" until the effects of the mishap are corrected.
The accident caused the space station to depressurize.  The situation
prompted quick action by the crew to seal off the affected Spektr module.

The accident has cut off US ham-astronaut Mike Foale, KB5UAC, from
his sleeping quarters and personal items in the Spektr module.  NASA
Shuttle-Mir Program Manager Frank Culbertson said there was "no indication
of health and safety problems" among the crew members, but that some of
the experiments in the Spektr module may have been ruined.  Culbertson
said the collision with the Progress supply rocket happened as the crew
was "testing a new rendezvous technique" to be used if automatic docking
systems failed.  In addition to Foale, the Mir is staffed by Russian
cosmonauts Vasily Tsibliyev and Alexander Lazutkin.  Foale has been
aboard Mir since mid-May when he replaced Linenger.

Linenger told the press conference that it was too early to comment on
what the latest problem aboard Mir might mean for the future of the
11-year-old space station, which already has outlasted its anticipated
life span by six years.  Linenger said fire and decompression are the
two most dangerous things aboard a spacecraft "and we've had both of
those."  During Linenger's four months aboard Mir early this year,
the crew experienced a fire, a near collision with another cargo
rocket, and coolant system leaks. 

Culbertson said repairs likely would require a space walk by the Mir
crew.  He also did not rule out the possible termination of the mission.
As part of its response to the emergency, the crew prepared the Soyuz
escape vehicle for possible evacuation.  Culbertson said the crew would
have to orient the station for optimal exposure to the sun to make the
best possible use of the solar panels that remain on-line.

For news updates, see http://www.hq.nasa.gov/office/pao/NewsRoom/today.html.

[Info via ARRL bulletin ARLS021]


* RESULTS OF MIR FREQUENCY CHANGE *
===================================
MIREX would like to thank all of the stations who participated in the week
long Mir frequency experiment.  The temporary frequency change to 145.985 MHz
simplex proved to be a big success around the world.

There were two primary reasons for test.  First, the Mir crews have been
complaining that the 145.200 MHz/145.800 MHz frequencies have too many
repeaters on it to hear stations calling Mir.  The Mir crews did not like
the noise, so the Mir crews would turn off the 2-meter station for weeks
at time.

The second reason for the test was to find out if there is a frequency
that can be used to avoid a desensing problem.  The Mir station operates a
commercial transmitter on 143 MHz.  This commercial transmitter is on most
of the time, including when Mir passes over Europe, Asia and the USA.
Whenever this commercial transmitter is active, it makes the 2-meter
station deaf.

The MIREX team has been performing may unpublicized frequency tests with
Mir over the past several months trying to solve the desensing problem.
Not only has MIREX been conducting on-the-air tests with Mir, but they
have also been conducting extensive test on the ground in their labs.
MIREX keeps identical Mir stations configured on the ground for testing
purposes.  MIREX has been conducting desensing and filter testing
experiments for the past year.  The closer the Mir receive frequency
is to the commercial channel, the worse the problem gets.  On 145.940 MHz,
the interference was a little less, and it was possible to punch thorough
the interference with 3000 watts ERP for a few moments when Mir was
directly overhead.  Ground stations should not be required to use this
much power for Mir access.  When Mir was on 145.550 MHz, most stations
were able to work Mir with 5 watts.  MIREX lab tests indicated that Mir
may be able to hear low power 2-meter stations if Mir moved its receive
frequency to 145.985 MHz (same frequency used by other FM satellites).

During the test, Mike Foale made many successful two-way contacts on
145.985 MHz while the commercial transmitter was active.  There still was
some interference from the commercial transmitter, but it has now been
proven that a working 2-meter frequency that meets ITU regulations can
be used for world wide access to Mir.  The MIREX team is currently working
on a special filter for the 2-meter station.  If the filter is approved,
it would allow Mir to access more of the 2-meter band without local
interference.  It should be noted that there are no reports of the
Amateur Radio equipment on board Mir ever causing interference to any
of the Mir commercial systems.

[Info via Dr. Dave Larsen, N6CO/K6MIR, MIREX President, and Miles Mann,
WF1F, Ed Dir.]


* TRACKING MIR ON THE WEB *
===========================
A World Wide Web site providing tracking of the Mir space station's
location in earth orbit is available at the following URL:

    http://liftoff.msfc.nasa.gov/temp/mir_loc.html

Another page that uses Java scripting is available at:

    http://liftoff.msfc.nasa.gov/RealTime/jtrack/

[Info via Bryan Todd, KS4HR]


* OSCAR-11 NEWS *
=================
During the period 15-May to 24-June good signals have once again been
received from the 145.826 MHz beacon.

Telemetry has been nominal.  The battery voltage has generally been
around 13.9 volts, but 14.4 volts has been recorded on one occassion,
and several over 14.0 volts has been noted.  The internal temperatures
have continued to fall due to solar eclipses.  The battery temperature
is now 0.2 degrees C (about 22 degrees below the full sunlight condition).

Three WOD surveys have been transmitted during the observation period.
Channels 0, 10, 20, 30 (-Y, +Y, -X, +X, solar array currents) dated
01-May continued.  This was followed by channels 17, 18, 19, 20 (+X, +Y,
+Z facet temperatures, & -X array current) dated 25 May.  Currently
channels 10, 20, 30, 40 (+Y, -X, +X array currents, array voltage)
dated 07-June is being transmitted.

Three AMSAT bulletins by Richard G3RWL have been uploaded.  Topics
have included the AMSAT-UK Colloquium, OSCAR-11 status, LUSAT and FO-20
information.  Bulletins always include current Keplerian elements for
OSCAR-11, and often for satellites featured in the bulletin.

The operating schedule is unchanged:

    ASCII status (210 seconds)
    ASCII bulletin (60 seconds)
    BINARY SEU (30 seconds)
    ASCII TLM (90 seconds)
    ASCII WOD (120 seconds)
    ASCII bulletin (60 seconds)
    BINARY ENG (30 seconds)

The Mode-S beacon is ON, but telemetry indicates that it has partially
failed, and is delivering half power.  It has been heard, but it is a
weak signal, and a good receiving setup is needed to hear it.  Any
reports of reception on 2401 MHz would be most welcome and should be
directed to g3cwv@amsat.org.

The 435.035 MHz beacon is normally OFF.  However, it can sometimes
be heard when the satellite is being commanded by ground control, ie.
within range of Guildford, UK.  Likely times are between 13:00 and
18:00 UTC, Fridays or at weekends.  It has, however, been heard at other
times, and recently was heard unexpectedly during an early morning pass
on Wednesday 21 May at 05:30 UTC.  When the 435 MHz beacon is transmitting,
the 145 beacon is normally OFF.  The data transmitted is mainly binary.

OSCAR-11 users are welcome to visit The Clive Wallis OSCAR-11 web site.
It contains some software for capturing data, and decoding ASCII telemetry
and WOD (whole orbit telemetry data).  There is an archive of raw data
(mainly WOD) for analysis, which is continually being expanded as new
data is captured.  The URL for the web site is:

    http://www.users.zetnet.co.uk/clivew/

[Info via Clive Wallis, G3CWV (g3cwv@amsat.org)]


* INDEPENDENCE DAY *
====================
On July 4th NASA's Mars Pathfinder spacecraft and its Sojourner rover will 
enter the Martian atmosphere.  If all goes well, the craft will survive the
entry and landing and be able to right itself.  The flower-like lander will
then open its petals.  Several hours later, the Sojourner rover will be
deployed.  Here's a schedule of the day's activities:

     Time (PDT)     Event

       07:00     JPL press briefing
       08:45     JPL landing commentary begins
       09:51     Mars atmosphere entry
       09:53     Parachute deployment
       09:55     Landing
    10:01-11:01  Receive first indication of a successful landing
       13:55     Receive first engineering and atmospheric entry data from 
                 lander
       15:30     JPL press briefing
    16:35-17:30  Receive first images of surface from lander
       18:00     Release of the first color panorama image of the surface
       21:00     Rover deployment
       23:00     JPL press briefing

The landing will be covered by NASA's TV channel, NASA Select.  Many cable 
TV providers offer NASA Select as a public service. i If you have a satellite 
TV setup, you can receive NASA Select directly from the satellite.  The
particulars are as follows:
    
    Satellite:   GE-2
    Position:    85 deg. W
    Transponder: 9C
    Frequency:   3880.0 MHz
    Audio:       6.8 MHz
                  
Another way to receive NASA Select is with a scanner.  Some ham radio
operators receive NASA Select and rebroadcast the audio over their repeaters.
In Los Angeles County and adjacent areas the best frequencies to monitor are
probably 147.150 and 448.500 MHz.  Other frequencies to check are 52.840, 
224.080, and 224.940 MHz.  NASA television video is sometimes available
through Amateur Television (ATV) repeaters that carry NASA TV video feeds.

A good source of information on the mission is the Internet.  A good place 
to start is JPL's web site at http://www.jpl.nasa.gov

[Info via Brian Webb, KD6NRP]


* FEEDBACK/INPUT WELCOMED *
===========================
Comments and input for SpaceNews should be directed to the editor (John,
KD2BD) via any of the paths listed below:
 
WWW       : http://www.njin.net/~magliaco/
PACKET    : KD2BD @ KS4HR.NJ.USA.NA
INTERNET  : kd2bd@amsat.org, magliaco@email.njin.net
SATELLITE : AMSAT-OSCAR-16, LUSAT-OSCAR-19


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