SB SAT @ AMSAT $ANS-348.01 OSCAR 13 MEAN MOTION-PREDICTED AND ACTUAL VALUES HR AMSAT NEWS SERVICE BULLETIN 331.01 FROM AMSAT HQ SILVER SPRING, MD DECEMBER 14, 1995 TO ALL RADIO AMATEURS BT BID: $ANS-348.01 Note: The associated plot is available via Internet: ftp://ftp.amsat.org/amsat/satinfo/ao13/mmplot.zip (14k) The most sensitive indicator of drag on any satellite can be found in the value of mean motion. As drag takes effect, mean motion increases, and the satellite appears earlier than if there were no drag. This effect is cumulative, and any earliness rapidly becomes very apparent. The effect of atmospheric drag is now clearly noticeable in the NORAD keplerian elements. The diagram MMPLOT.GIF (in mmplot.zip) compares the predicted value of Mean Motion with the NORAD values taken from all available 2-line element sets since 1995 Oct. 05. The predicted values of Mean Motion and other elements are based a model that includes a best estimate of the aerodynamic profile of the satellite. As time goes by, the agreement between predicted and actual Mean Motion will be used to improve this estimate, and so to improve re-entry predictions. MMPLOT.GIF will be updated whenever new NORAD data is issued. Regularly updated AO-13 decay information is available at: ftp://ftp.amsat.org/amsat/satinfo/ao13/decaykep.zip (13k) The program used for predicting AO-13's future integrates the equations of motion. Forces modeled are Earth's gravity up to degree 8, zonal, tesseral and sectoral terms from the GEM10B model, Sun, Moon, atmospheric drag and solar radiation pressure. It is described and listed in: ftp://ftp.amsat.org/amsat/articles/g3ruh/a114.zip (107k) ANS thanks James Miller, AO-13 Command Station, for this bulletin /EX SB SAT @ AMSAT $ANS-348.02 CHANGE IN SKN PACKET ADDRESS HR AMSAT NEWS SERVICE BULLETIN 331.01 FROM AMSAT HQ SILVER SPRING, MD DECEMBER 14, 1995 TO ALL RADIO AMATEURS BT BID: $ANS-348.02 ANS has been advised that the WA2NDV-4 packet BBS will cease operation in a few weeks, so Ray, W2RS, IS moving HIS home BBS to WA2SNA, effective immediately. "Best Fist" nominations for OSCAR SKN should therefore be sent to W2RS @ WA2SNA or to W2RS @ GB7HSN, and not to W2RS @ WA2NDV. .. ANS thanks Ray Soifer W2RS for this bulletin. /EX SB SAT @ AMSAT $ANS-348.03 ZRO TEST UPDATE HR AMSAT NEWS SERVICE BULLETIN 331.01 FROM AMSAT HQ SILVER SPRING, MD DECEMBER 14, 1995 TO ALL RADIO AMATEURS BT BID: $ANS-348.03 ANS is happy to report that the first ZRO test of the current batch of three went well. It was scheduled for December 3rd at 2230 Z with a downlink of 145.840 MHz. Some problems were encountered with levels 0 and 1, but all subsequent levels through A were correct. Two tests remain; one on Saturday, December 16th at 1930 Z and one on Saturday December 23rd at 2330 Z. Send all reports to WA5ZIB (callbook address) .. ANS thanks WA2ZIB for this bulletin. /EX SB SAT @ AMSAT $ANS-348.04 APRtrack PROGRAM UPDATE HR AMSAT NEWS SERVICE BULLETIN 331.01 FROM AMSAT HQ SILVER SPRING, MD DECEMBER 14, 1995 TO ALL RADIO AMATEURS BT BID: $ANS-348.04 If you are going to be using APRtrak for the upcoming SPARTAN payload to be launched 11 January, be sure you get version 0.5. The first release was version 0.4 at the Orlando AMSAT conference in October. Its flaw is that it is STUCK in Eastern Daylight Time Zone. It will work by forcing your clock to EDT time zone, but there have been a few other improvements also, that should encourage you to get 0.5. You can see the version # on the start-up screen and on the F1-Help screen. Version 0.4 will be dated in October, and version 0.5 will be dated in November... Before 11 Jan, WB4APR will put out some helpful hints on operation. In the mean time, play with it. A good practice is to use it to monitor the MIR downlink. Read the various README files until then... Good luck. ANS thanks WB4APR for this bulletin. /EX SB SAT @ AMSAT $ANS-348.05 G0SYX TO GO QRT HR AMSAT NEWS SERVICE BULLETIN 331.01 FROM AMSAT HQ SILVER SPRING, MD DECEMBER 14, 1995 TO ALL RADIO AMATEURS BT BID: $ANS-348.05 ANS is sad to report that after three truly outstanding years with UoSAT/SSTL, Doug Loughmiller, G0SYX/KO5I, is leaving his post as Spacecraft Operations and Groundstation manager effective December 12th, 1995 to return to the United States. Loughmiller told ANS, 'In a way, this marks the end of a dream for me, as six years ago I made a conscious decision to make a mid-life career change to work in the small satellite field. It was my belief that people who place things into space are truly special people and I dearly wanted to be such a person. Over the past three years, my association with the people at UoSAT has proven my belief to be true beyond a shadow of a doubt. I am deeply grateful to have been extended the opportunity to become part of their team. But, unfortunately, the time has come for me to return to Texas to once again regain my place on the sidelines as a mere observer while pursuing other professional pursuits.' Loughmiller is pleased that he will be leaving the UoSATs in the good hands of Chris Jackson, ZL2TPO/G7UPN. Chris, who as we all know is the author of the very popular WISP program, joined UoSAT about a year ago and has been a valuable addition to the UoSAT family. Chris has a very bright technical mind and is one of the true innovators in amateur radio today. Loughmiller has had the opportunity to work closely with Chris and have always found him friendly and helpful. He will be an outstanding guardian of the UoSATs and I wish him all the best. ANS thanks Doug Loughmiller G0SYX/KO5I for this bulletin. /EX AO-13 SCHEDULES 1996 ******THIS BULLETIN HAS ALREADY GONE OUT OVER PACKET. DO NOT FORWARD OVER PACKET.******** [ Note: If you forward this in any way to the packet network, ] [ you may change the "WW" or the "AMSAT", but DO NOT alter or ] [ remove the BID $RUH951201 above. Helps prevent duplicates. ] Attitude Schedule ----------------- The planned attitude schedule for Oscar 13 during 1996 is: Date [Mon] Alon/Alat Weeks -------------------------------- 1996 Jan 01 220/0 13 1996 Apr 01 180/0 10 1996 Jun 10 220/0 t.b.a. -------------------------------- The session beginning 1996 June 10 will also last for about 3 months. After that, 1996 September, perigee height will be 170 km and re-entry effects will already be noticeable. This will be an interesting time, and the command team welcomes suggestions which we could implement to make use of this unique opportunity to observe an amateur spacecraft at re-entry. Full details of re-entry, around 1996 Dec 05-19, can be found in: - Proceedings of the 12th annual Amsat Space Symposium, Orlando, Florida, USA, 1994. 4 pages. - Oscar News (UK) 1994 Oct No. 109 p 16-20 - Jamsat Newsletter (JA) No. 166, 1995 March 25. p1-4 - Amsat-DL Journal (D), Jg. 22, No. 1, Mar/May 1995. - Amsat OZ Journal (OZ) No. 37, 1995 May - The Amsat Journal (USA) Vol 18 No.3, May/June 1995. The article and regularly updated program listing is available via the Internet by anonymous FTP: Site: ftp.amsat.org File: /amsat/articles/g3ruh/a114.zip (Article) File: /amsat/satinfo/ao13/decaykep.zip (Decay keplerian elements) Mode Schedule ------------- M QST ** AO-13 TRANSPONDER SCHEDULE ** 1995 Dec 02 - 1996 Jan 01 Mode-B : MA 0 to MA 70 | Mode-BS : MA 70 to MA 110 | Omnis : MA 230 to MA 25 Mode-S : MA 110 to MA 112 |<- S beacon only Mode-S : MA 112 to MA 135 |<- S transponder; B trsp. is OFF Mode-S : MA 135 to MA 140 |<- S beacon only Mode-BS : MA 140 to MA 180 | Alon/Alat 182/0 Mode-B : MA 180 to MA 256 | Move to attitude 220/0, Jan 01 Please note that the higher powered engineering beacon 145.985 MHz is ON for two periods: MA 0 - 20 and MA 100-110. Provisional Schedule -------------------- N QST *** AO-13 TRANSPONDER SCHEDULE *** 1996 Jan 01 - Apr 01 Mode-B : MA 0 to MA 140 | *** P R O V I S I O N A L Mode-BS : MA 140 to MA 240 | Mode-B : MA 240 to MA 256 | Alon/Alat 220/0 Omnis : MA 250 to MA 140 | Move to attitude 180/0, Apr 01 If In Doubt Invent It Department (IID^2) ---------------------------------------- Continuous up-to-date information about AO-13 operations is always available on the beacons, 145.812 MHz or 2400.664 MHz, in CW at 0 & 30 minutes past the hour, RTTY at 15 & 45 minutes past the hour and 400 bps PSK otherwise. These bulletins are also posted to Internet, ANS, Packet, PacSats etc, and many international newsletters. A 400 bps PSK decoder is available from G3RUH and several DSP products; display software P3TLM, WINSAT, P3C.EXE (MS-DOS); !TLM13 (RiscOS) etc from Amsat groups. Internet users wanting the latest AO-13 information should always check: ftp://ftp.amsat.org/amsat/satinfo/ao13/ http://www.amsat.org/amsat/ Telemetry is archived at: ftp://ftp.amsat.org/amsat/satinfo/ao13/telemetry/ The active command stations are listed below, and constructive feedback about operations is always welcome. Peter DB2OS @ DB0FC.#NDS.DEU.EU James G3RUH @ GB7DDX.#22.GBR.EU Graham VK5AGR They may also be reached via Internet (callsign@amsat.org) and KO-23. Please remember to state clearly a return address. Notes prepared on behalf of, and in cooperation with the above by: James Miller G3RUH @ GB7DDX.#22.GBR.EU 1995 Dec 01 [Fri] 1521 utc ANS thanks James Miller, AO-13 Command Station, for this bulletin