Release 20171002 NuSTAR CALDB Release Version: 20171002 Release Type: Clock Correction Update Summary of changes: CLOCK: NuSTAR clock correction file, version 75, is available. This file is up to date through 2017-10-02. See http://www.srl.caltech.edu/NuSTAR_Public/NuSTAROperationSite/clockfile.php There are a few days when there are deviations outside the spline fit: plot_X DOY Date 2796 2017:241 2017-08-29 2801 2017:246 2017-09-03 2811 2017:256 2017-09-13 2817 2017:262 2017-09-19 which may correspond to the recent Solar activity (multiple CME and X-class flares); however there is no clear correlation as these events occurred between DOY 247 to 251 (2802 to 2806 on the plot). In addition, there was a steady drift between 2821 < X < 2826 when no automatic adjustments were performed to the onboard clock frequency due to a timing calibration observation of PSR B1821-24 (DOY 266-270, 2017-09-23 to 27th). The clock appeared to have a slow steady drift of up to ~ 40 ms by the end of this period.