STEREO Weekly Meeting Minutes for 2019-07-09 (Week 28) ANNOUNCEMENTS ------------- * The SSC reports that all ftp servers at NASA will have to be shut down by July 31. Instrument teams that get their data via ftp from the stereoftp server will have to change their scripts to get the data from https://stereo-ssc.nascom.nasa.gov. A new procedure for updating SolarSoft is in beta testing. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally. * Four years after the initial loss of communications anomaly with the Behind observatory, NASA has directed to cease periodic recovery operations with the last support on October 17, 2018. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 27 (Jul 1-7) * On day 183 (Tuesday July 2), the SECCHI instrument reset at 09:04:55z. The SECCHI team reconfigured the instrument to operational mode by 184-0825z. This was the 54th reset of the SECCHI instrument on the Ahead observatory. * On day 186 (Friday July 5), a DSS-25 Return-to-Service (RTS) Demonstration track was conducted to verify X-band tracking, telemetry and command operations after azimuth wheel replacement * On day 187 (Saturday, July 6), during the DSS-14 support, the antenna was stowed from 0319z to 0420z (EOT) due to a 7.1 magnitude earthquake. This anomaly resulted in the loss one hour of commanding, real-time telemetry, and SSR data. On the subsequent DSS-36 support, the SSR pointers were repositioned and all affected data from the DSS-14 was recovered. See DR #G120327 for more information. * On day 188 (Sunday July 7), during the DSS-14 support, the antenna was red for the entire duration (3.3 hours, 0100z to 0420z) due to a RF-IF downconverter anomaly. This anomaly resulted in the loss 3.3 hours of commanding, real-time telemetry, and 33.1 hours of SSR data. See DR #G120340 for more information * The average daily science data return for Ahead was 4.4 Gbits during this week. Week 28 (Jul 8-14) * Today Monday, July 9, during Station 34 support turbo decoder lock was lost. Lost 2 frames SSR data. * The launch of Chandrayaan-2 is scheduled for July 14, at 21:21 UTC. Launch contingencies affect the DSN schedule for STEREO in the following weeks. * Ahead has eleven passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, two at 360 kbps, and one at 240 kbps. Week 29 (Jul 15-21) * STEREO will loose Station 36 coverage on Thursday July 18 if the Chandrayaan-2 launch shifts to the day 3 or day 4 launch opportunities. * Ahead has ten passes during the week, and overall coverage is nominal. There are five passes at 720 kbps, four at 360 kbps, and one at 240 kbsp. Week 30 (Jul 22-28) * Ahead has nine passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, and one at 240 kbps. Week 31 (Jul 29-Aug 4) * The 49th SECCHI stepped calibration roll is scheduled for Monday, Jul 29, starting at 12:10 UTC. This is the midpoint roll. System momentum is expected to be 7 N-m-s. This will be the 18th calibration roll without using the gyros. * Ahead has nine passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, one at 360 kbps, and two at 240 kbps. Week 32 (Aug 5-11) * The 121st momentum dump on Ahead is scheduled for Monday, Aug 5, with ignition at 20:30 UT. This will be the 40th momentum dump without using the gyros. * On Tuesday, Aug 6, the data rates for the low gain antenna on Ahead will increase to 500 bps for uplink, and 1000 bps for downlink, when using a 70 meter station. * Ahead has ten passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, one at 360 kbps, and one at 240 kbps. Week 33 (Aug 12-18) * Late on Tuesday Aug 13 there will be a project interface test of software and procedures for three links per operator at the DSN. No SSR playback or instrument commanding during the test. * Ahead has eleven passes during the week, and overall coverage in nominal. There are seven passes at 720 kbps and four at 240 kbps. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 08 (189) T Jul 09 (190) W Jul 10 (191) T Jul 11 (192) F Jul 12 (193) S Jul 13 (194) S Jul 14 (195) ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 15 (196) T Jul 16 (197) W Jul 17 (198) T Jul 18 (199) F Jul 19 (200) S Jul 20 (201) S Jul 21 (202) ------------------------------------------------------------------------------- Scheduled activities for Week 30: M Jul 22 (203) T Jul 23 (204) W Jul 24 (205) T Jul 25 (206) F Jul 26 (207) S Jul 27 (208) S Jul 28 (209) ------------------------------------------------------------------------------- Scheduled activities for Week 31: M Jul 29 (210) Ahead: SECCHI stepped calibration roll, 12:10 UT T Jul 30 (211) W Jul 31 (212) T Aug 01 (213) F Aug 02 (214) S Aug 03 (215) S Aug 04 (216) ------------------------------------------------------------------------------- Scheduled activities for Week 32: M Aug 05 (217) Ahead: Momentum dump, 20:30 UT T Aug 06 (218) W Aug 07 (219) T Aug 08 (220) F Aug 09 (221) S Aug 10 (222) S Aug 11 (223) ------------------------------------------------------------------------------- Scheduled activities for Week 33: M Aug 12 (224) T Aug 13 (225) W Aug 14 (226) T Aug 15 (227) F Aug 16 (228) S Aug 17 (229) S Aug 18 (230) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 2019: * Aug 28-Sep 7 Parker Solar Probe perihelion pass * Nov 4 Ahead: Close approach of Parker Solar Probe * Dec 26 Parker Solar Probe Venus flyby 2020: * Jan 24-Feb 4 Parker Solar Probe perihelion pass * May Behind: Switch downlink rate to 360 kbps for 34 meter * Jun Ahead: Switch downlink rate to 360 kbps for 34 meter * Jun Behind: Switch downlink rate to 480 kbps for 34 meter * Jun 2-13 Parker Solar Probe perihelion pass * Jul 11 Parker Solar Probe Venus flyby, in HI2-A field-of-view * Sep Ahead: Switch downlink rate to 480 kbps for 34 meter * Sep 22-Oct 2 Parker Solar Probe perihelion pass 2021: * Jan 13-23 Parker Solar Probe perihelion pass * Feb 20 Parker Solar Probe Venus flyby * Apr 25-May 4 Parker Solar Probe perihelion pass * Jul Behind: Switch downlink rate to 720 kbps for 34 meter * Aug Ahead: Switch downlink rate to 720 kbps for 34 meter * Aug 5-15 Parker Solar Probe perihelion pass * Oct 16 Parker Solar Probe Venus flyby * Nov 17-26 Parker Solar Probe perihelion pass 2022: * Feb 21-Mar 2 Parker Solar Probe perihelion pass * May 28-Jun 7 Parker Solar Probe perihelion pass * Sep 2-11 Parker Solar Probe perihelion pass * Dec 7-16 Parker Solar Probe perihelion pass 2023: * Mar 13-23 Parker Solar Probe perihelion pass * May 5 Behind: Mercury transit * Jun 17-27 Parker Solar Probe perihelion pass * Jul 17 Behind: Closest approach to Earth * Aug 13 Ahead: Closest approach to Earth * Aug 21 Parker Solar Probe Venus flyby * Sep 23-Oct 3 Parker Solar Probe perihelion pass * Dec 25-Jan 3 Parker Solar Probe perihelion pass 2024: * Mar 26-Apr 4 Parker Solar Probe perihelion pass * Jun 26-Jul 5 Parker Solar Probe perihelion pass * Sep 26-Oct 5 Parker Solar Probe perihelion pass * Nov 6 Parker Solar Probe Venus flyby, in HI2-A field-of-view * Dec 20-29 Parker Solar Probe perihelion pass 2025: * Mar 19-27 Parker Solar Probe perihelion pass * Apr 7 Ahead: Mercury transit * Jun 15-24 Parker Solar Probe perihelion pass 2026: 2027: * Feb 1 Behind: Mercury transit 2028: 2029: * Jun 30 Ahead: Mercury transit