home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Ham Radio
/
Ham Radio CD-ROM (Emerald Software) (1995).ISO
/
news
/
amsat245
/
amsat245.txt
Wrap
Text File
|
1989-09-06
|
6KB
|
131 lines
**************************************************************************
* *
* THIS IS THE WD0GML-AMSAT-ST.LOUIS BBS 24HR 7DAY AT (314)447-3003 *
* 300/1200/2400 BAUD *
* Mike Parisey WD0GML SYSOP *
* Norm Newman NZ0Z Co-SYSOP *
* *
**************************************************************************
NOTICE!
Due to a coincident set of unfortunate circumstances, Dave Cowdin
will be unable to produce an edition of ANS this weekend and the
backup group has also been unable to respond in time. Doug has
instructed that Net Control stations should use last week's
bulletins again this week, using editorial judgment concerning
what is still timely and appropriate. Also, be sure to mention
that OSCAR-10 is now unavailable for use until at least November.
We regret any inconvenience or difficulty that this may cause. Please
understand that it is just another symptom of the very hectic
situation that many AMSAT personnel including Dave and most of the
other managers are currently experiencing.
ANS will resume next week.
Thanks for your understanding and 73,
Courtney Duncan, N5BF, VP Operations
OSCAR 10 NEWS:
OSCAR 10 is now in eclips and is out of service untill on or around
the 1st of NOV 89.
OSCAR 13 NEWS:
OSCAR 13 Element Set No. 45 appears to be in error, we are looking into
this problem. This weeks elements include set #46.
NEW ITEMS ON THE BBS:
Check the Applications Section of the Download/Upload Area for a Weather
Satellite Image Processing Program Demo. Its in 5 parts, the Main Program, and
4 Photo files you only need the one that matches the type of display you have
ie CGA, EGA, VGA.
Check the Ham Forum Section of the Download/Upload Area for a contest
dupeing program, some may find it of interest.
UoSAT 9 NEWS:
The following report is from Rich Ensign, N8IWJ, AMSAT-NA's Science Education
Advisor:
The first of the English University of Surrey Amateur Radio Satellites
UoSAT 1, or OSCAR 9, is continuing its slow fall to Earth. At launch
(October 6, 1981) OSCAR 9 was in a polar orbit some 554 kilometers high. Now,
almost 8 years later, OSCAR 9's circular orbit has dropped to less than 343
kilometers. At launch, OSCAR 9 completed one orbit in 95 minutes. Now, at its
lower altitude, the satellite orbits in 91 minutes. Atmospheric drag is the
culprit that has destined this longest operating of amateur radio satellites
to a meteoric fate this fall.
When OSCAR 9 was launched, the Sun had passed the peak of the last solar
activity cycle. These solar activity cycles of eleven years raise the
temperature of the Sun's photosphere slightly due to increased numbers of
flares and accompanying sunspots. This, in turn, increases the number of
solar wind particles reaching the Earth. Earth's upper atmosphere is heated
and expands outward, bringing low Earth orbiting satellites within its
frictional envelope. The satellite slows and begins to curve downward into
higher air densities. Unless the satellite has some means of boosting its
orbit, it is doomed to burn up in the atmosphere. Since there is no kick
motor on board the satellite, its controllers and users, will have to accept
its fate.
It has been interesting to compare the drag numbers in the weekly
orbital elements with the number of sunspots on the sun at corresponding
times. Graphs of both sets of data have matching dips and peaks and the slope
of OSCAR 9's descent rate also correlates. You can follow this yourself by
using the NASA orbital element information provided by AMSAT each week and
looking up corresponding sunspot numbers for the same epoch day in the
monthly astronomy publication, Sky and Telescope. These numbers are published
with a three month delay so the most recent numbers go to the end of June.
AO-9's descent rates recently have varied between 0.4 and 1.1 kilometers
per day. This rate will increase as the spacecraft falls to depths of ever
increasing density. The spacecraft should reach a point where it literally
falls out of the sky in a blazing streak in mid-October. The spacecraft will
most probably be totally consumed in its descent. Exactly when and where this
will happen depends on a number of factors and will be of great interest to
many OSCAR watchers. Stay tuned AMSAT Nets and publications for further
information. An excellent information source is also the weekly bulletins on
UO-11, another Surrey satellite.
NEWS FROM SA AMSAT:
New Committee:
At the recently held Annual General Meeting Hans van de
Groenendaal ZS6AKV was re-elected as President of SA AMSAT
for a period of two years. Vice President is Tony Reumerman
ZS6AOG, Treasurer Theo Swart ZR6SG , Secretary Willem Nel
ZS6ALL , Transvaal Regional Co-ordinator Gerald Klatzko
ZS6BTD. The SA AMSAT committee appointed Hennie Rheeder
ZS6ALN as Satellite Project Engineer, Dave Woodhall as BACAR
Project Engineer and Piet van Schie ZS6AQC as Editor of
Satellite News Update.
SATELLITE PROJECTS:
SA AMSAT has in principle agreed to work with AMSAT DL and
will be developing an AM compatable SSB mode A Transponder
for educational use on the planned Phase 3D satellite. In
addition the group is also planning to build a microsat with
digital store and forward capability to provide data traffic
flow between various PBBS's in Southern Africa. A mode A
transponder is also under discussion. After the initial
announcement various South African universities have
expressed interest in the projects.
BACAR TO FLY 6 M Transponder:
On September 23 BACAR mission 2/89 will include a 6 metres
transponder. Frequencies are : Uplink: 51,400 MHz, downlink:
145,925 MHz . The transponder will operate between 06h00 and
08h00 UTC .
73 Hans ZS6AKV.