STEREO Weekly Meeting Minutes for 2007-08-28 (Week 35) ANNOUNCEMENTS ------------- * None. INSTRUMENT AND SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal, except that the Ahead spacecraft is currently operating on IMU #2. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 34 * Day 234: There was a real time drop out for Ahead on Antenna 26 at 09:57 UT resulting in a two minute gap in the SSR data. This was the result of a DSN equipment problem. * Average daily downlink for the week was 7.6 gigabits for Ahead and 7.8 gigabits for Behind. Week 35 * Today the IMPACT team will be doing a new table upload for SEP SIT on Behind. This will take about 30 min. Week 36 * No special events are scheduled. Week 37 * Day 255 (Sept. 12) is the 1st launch opportunity for SELENE, a Japanese mission which has requested DSN time to augment the Japanese ground system. At this time it does not look like this will affect STEREO very much - just some small shifts in the times of our passes. * Days 254 and 255 PLASTIC table upload on Behind (see last week's minutes for more details). This had previously been expected to begin Week 36. Week 38 * PLASTIC table upload expected for Ahead on two days this week Other Future events: * S/WAVES expects to need need a day on each spacecraft for memory loads in the second half of September (Week 38 or 39). They will need time again a week or two later * Sept. 26 (Week 39, Day 269) - Momentum dumps are currently scheduled on Ahead and Behind for this day. However, it is also the 1st launch opportunity for Dawn, which is likely to affect the STEREO DSN schedule. We will know more when the DSN schedule for Week 39 issued. * Oct. 3. (Day 276) HGA quarterly calibration on Ahead and Behind. 7 hours tracks are scheduled. Other: * Last week it was mentioned that the total recorder playback time will be reduced by 3 min at a future date. Although the date for that is not set, it looks like this will not be as soon as was previously thought - it will probably not be for a couple months. * S/WAVES voltage spike report. Last spring Keith was asking spacecraft and instrument teams to help investigate a series of mysterious spikes in the S/WAVES voltage levels. Now he and Mike think that these are the result of micron sized dust particles hitting the spacecraft and vaporizing, leading to voltage pulses in the S/WAVES antennas. These particle would mostly be zodiacal dust particles, although comet tails could also be contributors. The dust densities they are calculating are much higher than expected, perhaps because they are detecting particles much smaller than have been considered before. PLASTIC or the IMPACT electron detectors might be able to detect the larger potential changes. Two times they could check would be July 27 2:30-5:00 UT positive voltage change on Ahead Aug. 7 1:30-07:00 UT positive voltage change also on Ahead. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 27 (239) T Aug 28 (240) W Aug 29 (241) T Aug 30 (242) F Aug 31 (243) S Sep 01 (244) S Sep 02 (245) ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Sep 03 (246) T Sep 04 (247) W Sep 05 (248) T Sep 06 (249) F Sep 07 (250) S Sep 08 (251) S Sep 09 (252) ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 10 (253) T Sep 11 (254) W Sep 12 (255) T Sep 13 (256) F Sep 14 (257) S Sep 15 (258) S Sep 16 (259) ------------------------------------------------------------------------------- Upcoming events: 2007: * Sep 26 1st Dawn launch opportunity * Oct 21 - Nov 16 JOPs 190,191,192 * Nov 02 - Nov 16 SUMER campaign * Nov (TBD) JOP 193 * Dec 2007-May 2008 Ulysses quadrature