PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2007-07-27 NOTE = " E-mail and other messages concerning MGS Radio Science on or about 1997/300." END_OBJECT = TEXT END From trish@rodan.jpl.nasa.gov Mon Oct 27 14:48:13 1997 Received: from rodan.Jpl.Nasa.Gov (rodan.jpl.nasa.gov [128.149.43.24]) by magellan.Stanford.EDU (8.8.5/8.8.3) with ESMTP id OAA19260 for ; Mon, 27 Oct 1997 14:48:13 -0800 (PST) Received: from 128.149.43.27 (trish-mac.jpl.nasa.gov [128.149.43.27]) by rodan.Jpl.Nasa.Gov (8.8.5/8.6.6) with SMTP id OAA19906; Mon, 27 Oct 1997 14:47:52 -0800 (PST) Message-Id: <199710272247.OAA19906@rodan.Jpl.Nasa.Gov> Date: 27 Oct 97 14:50:16 -0800 From: Trish Priest Subject: Data on TDS and Biollante To: Richard Simpson , Joe Twicken X-Mailer: QuickMail Pro 1.0.2d1 X-Priority: 3 Reply-To: Trish Priest Content-Type: text/plain; charset="iso-8859-1" Content-Length: 546 Status: R Hello, Data from DOY 296 and DOY 300 are on the TDS. Paula has queried for the data, and it is available on biollante in /ftp/mgs as a final resort. File names are doy296.ods and doy300.ods. DOY 300 data times are 19:47:00 to 21:07:00. The data are LGA, one-way, telemetry off, ranging off, 5000 sps, 12-bit. I hope that this is an indication of things to come. The DOY 300 data was on the TDS with no missing records only an hour after we idled the DSP. -Trish ------------------------------------------------------------------------ -------------------------------------------------------------------------- From trish@rodan.jpl.nasa.gov Mon Oct 27 16:56:56 1997 Received: from rodan.Jpl.Nasa.Gov (rodan.jpl.nasa.gov [128.149.43.24]) by magellan.Stanford.EDU (8.8.5/8.8.3) with ESMTP id QAA20339 for ; Mon, 27 Oct 1997 16:56:45 -0800 (PST) Received: from 128.149.43.27 (trish-mac.jpl.nasa.gov [128.149.43.27]) by rodan.Jpl.Nasa.Gov (8.8.5/8.6.6) with SMTP id QAA20615; Mon, 27 Oct 1997 16:56:23 -0800 (PST) Message-Id: <199710280056.QAA20615@rodan.Jpl.Nasa.Gov> Date: 27 Oct 97 16:58:48 -0800 From: Trish Priest Subject: P27 through P29 Timing To: Georges Balmino , Frank Lemoine , Richard Simpson , Bill Sjogren , David Smith , Joe Twicken , Len Tyler , Maria Zuber X-Mailer: QuickMail Pro 1.0.2d1 X-Priority: 3 Reply-To: Trish Priest Content-Type: text/plain; charset="iso-8859-1" Content-Length: 1948 Status: RO Hello, The following are times for events on periapses 27 through 29. The times are in ERT UTC. One-way data from the LGA was collected (open-loop and closed-loop to the DSN capability). Telemetry and ranging are off. The LGA pointing geometry was the same as it was for P26. -Trish ------------------------- Times are from SOE and are expected times for the given events. Some Block-V lock times must be retrieved from the LMC logs. ... Periapsis 29 DSS 15 DOY 300 19:46:00 Turn off MOT and RPA beam 19:46:07 Turn on MOT on LGA (telemetry and ranging off) 19:50:16 Station acquire 1-way 20:01:07 Spacecraft start turn off-Earth 20:01:08 LOS expected ? Block-V Receiver out of lock 20:26:37 Periapsis 28 20:46:09 Spacecraft start turn back to Earth point ? Block-V Receiver back in lock 20:58:10 Station acquire 1-way - expected 21:07:00 Turn off MOT and RPA beam 21:07:00 Turn on MOT on HGA ------------------------------------------------------------------- -------------------------------------------------------------------------- From joe@neptune.Stanford.EDU Wed Oct 29 10:28:41 1997 Received: from nova.stanford.edu (nova.Stanford.EDU [36.10.0.123]) by magellan.Stanford.EDU (8.8.5/8.8.3) with ESMTP id KAA24021 for ; Wed, 29 Oct 1997 10:28:41 -0800 (PST) Received: from neptune.Stanford.EDU (neptune.Stanford.EDU [36.10.0.149]) by nova.stanford.edu (8.8.5/8.8.4) with ESMTP id KAA22638; Wed, 29 Oct 1997 10:28:41 -0800 (PST) Received: (from joe@localhost) by neptune.Stanford.EDU (8.8.5/8.8.3) id KAA23296; Wed, 29 Oct 1997 10:27:30 -0800 (PST) Date: Wed, 29 Oct 1997 10:27:30 -0800 (PST) From: Joe Twicken Message-Id: <199710291827.KAA23296@neptune.Stanford.EDU> To: rsimpson@nova.Stanford.EDU Cc: len@nova.Stanford.EDU Subject: MGS LGA Antenna Pattern Content-Length: 1632 Status: R I have estimated the MGS LGA antenna pattern using the ODR data from 97/296 and 97/300. The postscript file with the pattern is called "pattern.ps" and is in my home directory on magellan. I used SP- and C-kernels to determine the off-boresight angle during the times that the open-loop data were acquired. I assumed that the LGA boresight is aligned with the +X direction in the spacecraft coordinate system. After filtering and steering the open-loop data, I estimated the carrier power for the duration of the two data sets at a rate of once per 6.5 seconds. During the periods when the LGA was moving off-Earth and then on-Earth, I eye-balled a smooth fit through the carrier power estimates. That is a very subjective procedure. I determined the carrier power every 0.005 hours (18 seconds) from the smooth fits and also determined the the LGA offboresight angles at the same instants. The antenna pattern is plotted relative to a maximum of 0 dB. I have shown the individual estimates of the pattern. There were two sets of estimates from each recording: one when the LGA moved off-Earth and one when the LGA moved back on Earth. The character of the pattern when the LGA was moving back on Earth was somewhat different than when it was moving off Earth. This is likely due to differing slices through the actual 2-D antenna pattern. The difference when the LGA was moving back on Earth is a slight dip (up to 1 dB) in the radiated power when the off-boresight angle was between about 15 and 35 degrees. The half power (-3 dB) point appears to be between 45 and 50 degrees and the -6 dB point is at about 62-63 degrees.