03 July 2019: Lightsail 2 Mission Manager's Log

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Telemetry beacons from LightSail 2 were decoded by a Riyadh, Saudi Arabia ground station, part of the SatNOGs amateur satellite network. The initial health and status assessment showed that the spacecraft was in good condition, with the batteries well charged. Temperatures were within the expected ranges. The attitude control subsystem was in detumble mode, angular rates were low (< 2 deg/s), and torque rod currents were low (z-axis torque rod current was zero). The +Y solar panel was shown as deployed in telemetry, however, this is most likely due to slack in the Spectraline that restrains the solar panels.

The flight team established two-way communications with the spacecraft and began housekeeping activities. The recurring autonomous antenna deployment process was disabled, and a file listing was downlinked. The error in the spacecraft clock was determined, and an updated two-line element (TLE) orbit state was uplinked to the spacecraft. The spacecraft clock was then updated, which resulted in an expected spacecraft reboot. Detailed attitude determination and control system information was downlinked for assessment. Commands to downlink stored telemetry files were unsuccessful, possibly due to errors in antenna pointing and uncertainty in the TLE. The positioning of the Cal Poly tracking station will be verified during daylight hours. It is expected that the 18th Space Control Squadron will publish a TLE specific to LightSail 2 within the next day, which will improve antenna pointing performance.