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 1998/026." END_OBJECT = TEXT END From trish@rodan.jpl.nasa.gov Mon Jan 26 05:42:07 1998 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 FAA25321 for ; Mon, 26 Jan 1998 05:41:57 -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 FAA16177; Mon, 26 Jan 1998 05:41:54 -0800 (PST) Message-Id: <199801261341.FAA16177@rodan.Jpl.Nasa.Gov> Date: 26 Jan 98 05:48:20 -0800 From: Trish Priest Subject: MGS Occultation #3 To: David Hinson , Richard Simpson , Joe Twicken , Len Tyler , Richard Woo CC: Salvadore Abbate , Sami Asmar , Jennifer Caetta , Mick Connally , Paula Eshe , Tom Thorpe X-Mailer: QuickMail Pro 1.0.2d1 X-Priority: 3 Reply-To: Trish Priest Content-Type: text/plain; charset="iso-8859-1" Content-Length: 1374 Status: RO Hello, The third occultation hit the surface of Mars. We saw the signal disappear from the SSI display. The amplitude varied quite a bit. The DSP recorded throughout. No problems were encountered. Although we used DSN-generated predicts for the occultation, we used our own predicts for a period of one-way after periapsis. The signal remained centered in the display. There were no errors or problems. This observation was over DSS 65. The usual configuration was used. We changed the attenuation three times at the beginning of the recording period (the latest was before 11:47:40). DSP Record Times: 026-11:42:00 to 026-12:00:00 One-way Period: 026-11:42:43 to 026-11:58:44 Expected Occultation Time: 026-11:56:44 The signal disappeared from the SSI display on time. The observation ended 2 minutes after surface begin as specified by the aerobraking block parameters which were set at the reset meeting. Data from occultations 1 and 2 are on the CDR but have not yet made it to the TDS. The appropriate people have been notified by e-mail. The data from DOY 025 have no missing records according to the CDR record count. The next occultation is at approximately 11:40 PM this evening over DSS-45. I will be in this afternoon (about 1:30 PM) if you have any questions. Or you can page me anytime at 1-800-sky-8888 pin 1134645. -Trish --------------------------------------------------------------------- From trish@rodan.jpl.nasa.gov Mon Jan 26 05:45:27 1998 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 FAA25328 for ; Mon, 26 Jan 1998 05:45:26 -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 FAA16189; Mon, 26 Jan 1998 05:45:26 -0800 (PST) Message-Id: <199801261345.FAA16189@rodan.Jpl.Nasa.Gov> Date: 26 Jan 98 05:51:53 -0800 From: Trish Priest Subject: P.S. 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: 118 Status: RO The pertinent files are OPTG: optg_i_980124_OD105_130_V1 SPK: spk_i_980124_OD105_130_V1 SOE: p106a.02.soe -Trish ----------------------------------------------------------------------- From rsimpson Fri Jan 30 09:58:54 1998 Received: (from rsimpson@localhost) by magellan.Stanford.EDU (8.8.5/8.8.3) id JAA19186; Fri, 30 Jan 1998 09:58:53 -0800 (PST) Date: Fri, 30 Jan 1998 09:58:53 -0800 (PST) From: Dick Simpson 723-3525 Message-Id: <199801301758.JAA19186@magellan.Stanford.EDU> To: rsimpson@magellan.stanford.edu, trish@rodan.jpl.nasa.gov Subject: Re: Data #5 and signal level Cc: hinson@nimbus.Stanford.EDU, joe@neptune.Stanford.EDU, len@nova.Stanford.EDU Content-Length: 1013 You can see the 10 dB drop in the Monitor AGC, so that makes sense. But that still leaves us with about 6 dB -- on BOTH DSS 65 passes. ---------------------------------------------------------------------- From trish@rodan.jpl.nasa.gov Fri Jan 30 09:31:07 1998 Date: 30 Jan 98 09:37:43 -0800 From: Trish Priest Subject: Data #5 and signal level To: Richard Simpson X-Priority: 3 Hello, Dick, The data still end at 03:01:19. Also, I heard from Angus, the LMA telecom person. He suspects that the weather in Spain was the reason for the lower signal. On DOY 026 (the 17 dB loss) there was heavy snow. The AGC was 10 dB lower than expected as well, so it wasn't just the Radio Science equipment. I still have to check the LMC logs for other possiblities. Sal is still looking for possible reasons as well. -Trish ---------------------------------------------------------------------- From trish@rodan.jpl.nasa.gov Fri Jan 30 14:57:58 1998 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 OAA21393 for ; Fri, 30 Jan 1998 14:57:58 -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 OAA05020; Fri, 30 Jan 1998 14:57:55 -0800 (PST) Message-Id: <199801302257.OAA05020@rodan.Jpl.Nasa.Gov> Date: 30 Jan 98 15:04:32 -0800 From: Trish Priest Subject: Snow To: David Hinson , Richard Simpson , Joe Twicken , Len Tyler CC: Salvadore Abbate , Sami Asmar , Jennifer Caetta , Paula Eshe , Angus McMechen X-Mailer: QuickMail Pro 1.0.2d1 X-Priority: 3 Reply-To: Trish Priest Content-Type: text/plain; charset="iso-8859-1" Content-Length: 552 Hello, Sal Abbate verified that snow could definitely account for the 10 dB at DSS 65 on DOY 026. In the antenna feedcone, there is a window which protects the maser from rain, etc. The window has a blower which is supposed to blow rain off of the window. It can actually make the window icy, however, if the temperature is low. This would cause a signal level degradation. This applies to 70-m and HEF antennas. Both the close-loop and open-loop systems would see the same degradation. We are still looking into the other 6 dB. -Trish ---------------------------------------------------------------------- From rsimpson Fri Jan 30 15:10:29 1998 Received: (from rsimpson@localhost) by magellan.Stanford.EDU (8.8.5/8.8.3) id PAA21611; Fri, 30 Jan 1998 15:10:24 -0800 (PST) Date: Fri, 30 Jan 1998 15:10:24 -0800 (PST) From: Dick Simpson 723-3525 Message-Id: <199801302310.PAA21611@magellan.Stanford.EDU> To: hinson@nimbus.Stanford.EDU, joe@neptune.Stanford.EDU, len@nova.Stanford.EDU, rsimpson@magellan.stanford.edu, trish@rodan.jpl.nasa.gov Subject: Re: Snow Cc: Paula.M.Eshe@jpl.nasa.gov, Salvatore.F.Abbate@jpl.nasa.gov, Sami.W.Asmar@jpl.nasa.gov, angus.m.mcmechen@lmco.com, caetta@biollante.jpl.nasa.gov Content-Length: 215 For weather effects, there should be an increase in system temperature at the same time as the signal AGC is dropping. We've not been routinely extracting SNT from the Monitor data; but it might be worth doing so.