Apache Point Observatory 3.5m Telescope Night Log Sunday, August 16, 2026 PROG PI ASTRONOMER OBSERVER(S) -------------------------------------------------------------------- NM05 T.McQuaid T.McQuaid NM04 M.Prescott M.Prescott,J.Burchett ON-SKY PROG INSTRUMENT START FINISH -------------------------------------------------------------------- NM05 ECHELLE 22:23 22:48 NM05 ECHELLE 23:45 01:09 NM04 KOSMOS 01:16 05:28 PROG SCHEDULED WEATH EQUIP OBS NOT USED I/ROW/DTN START FINISH D B D B D B D B ----------------------------------------------------------------- NM05/R 19:56 01:10 1.3 2.1 0 0 1.8 0.0 0 0 NM04/R 01:10 06:20 0 0 0 0 5.2 0.0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: R.McMillan After some afternoon rains and areal flooding, there was fog nearby but the humidity at APO was not so high. The clouds took longer to clear, and as they moved off the dust rose. So we opened long enough to focus echelle but didn't get any data, closed for clouds and dust, then re-opened an hour later when dust was below the limit. It was still a bit of a struggle to get photons, with passing clouds and variable seeing. During second half, the clouds gradually thinned and the seeing stabilized. The tertiary mirror had another amplifier fault early in the evening, while the clouds were still thick. Cary came in and we discussed some workaround strategies. Additionally, a cluster of moth guts on the altitude drive surface caused many many motion errors. The telescope had to be pushed away from the moth area by hand so that it could be cleaned and then re-cleaned, but after that everything was fine. There was no trouble with the tertiary on the switch back to NA2 at changeover. We had some significant drift with KOSMOS, relying on the NA2 guider, but the drift did get a bit slower as the target field moved further from transit. ------- FAILURE LOG ------- FAILURE MODE TIME PROG INSTR TI/SHU START FINISH DESCRIPTION ---------------------------------------------------------------------- ---------------- FOCUS LOG --------------- Time Instrument Focus Az El Temp Strc Prim Sec Air filt FWHM -------------------------------------------------------------------------- 22:31 ecamera 409( 169) 148 64 13.7 14.1 15.1 14.0 13.8 Clear 1.37 01:28 kimage 350( 1054) -5 81 13.1 13.0 13.9 13.0 12.9 - 1.26 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:00 59 32 6 86 (E) 1693 cloudy rain 17:00 62 32 11 85 (E) 1465 cloudy lt rain 18:00 62 32 14 78 (ENE) 2515 cloudy humid 19:00 61 32 13 78 (ENE) 3264 cloudy none 20:00 61 31 16 79 (E) 3194 mstly cldy none 21:00 59 31 19 75 (ENE) 3644 mstly cldy none 22:00 59 31 16 87 (E) 3824 ptly cldy none 23:00 58 31 14 89 (E) 4158 ptly cldy dust 00:00 58 31 20 77 (ENE) 3845 ptly cldy none 01:00 56 30 23 84 (E) 3465 mstly clr none 02:00 55 31 21 80 (E) 3213 mstly clr none 03:00 54 30 19 72 (ENE) 3123 clear none 04:00 54 29 15 79 (E) 3080 clear none 05:00 54 30 15 78 (ENE) 3026 clear none 06:00 55 30 18 75 (ENE) 3480 clear none Note: the wind was coming from the azimuth listed. The convention used is north=0 degrees, east=90 degrees. The dust count is particles > 1u per 0.1 cubic feet. ---------- TELESCOPE SOFTWARE ---------- Current TCC version: 1.4.2 Current HUB version: v20171231_01 Current TUI version: 3.2.2