Apache Point Observatory 3.5m Telescope Night Log Tuesday, October 20, 2026 PROG PI ASTRONOMER OBSERVER(S) -------------------------------------------------------------------- AP02 S.Merkowitz R.McMillan, T.Sutherland UW01 P.Yoachim D.Meng, Z.Xu UV05 A.Verbiscer A.Verbiscer ON-SKY PROG INSTRUMENT START FINISH -------------------------------------------------------------------- AP02 APOLLO 18:33 19:06 AP02 APOLLO 21:00 21:50 UW01 KOSMOS 21:52 23:45 UV05 ARCTIC --:-- --:-- PROG SCHEDULED WEATH EQUIP OBS NOT USED I/ROW/DTN START FINISH D B D B D B D B ----------------------------------------------------------------- AP02/R 18:33 21:50 1.9 0 0 0 0.0 1.4 0 0 UW01/R 21:50 01:10 1.4 0 0 0 0.0 1.9 0 0 UV05/R 01:10 07:04 4.5 1.4 0 0 0.0 0.0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: J.Dembicky We opened but the humidity was on the rise. Since the telescope was warm we were able to stay open for a little under adverse conditions but around 19:00 the outside railing was now getting wet and it was time to close. I re-opeend at 21:00, closed due to humidity again at 23:45 The fire alarm panel alarm went off around 04:20. The LCD dispaly said all systems normal but alarm was still sounding. I did not see any lights indicating any alarm triggered on the board. I pressed the silence alarm and the sound went away. Nobody called from the monitoring service so I assume everything was fine. I gave up at 06:00 due to humidity conditions. ------- 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 -------------------------------------------------------------------------- 18:35 APOLLO 550( 2128) 40 31 11.1 14.7 13.1 14.3 12.1 -- 1.50 21:06 APOLLO 350( 1799) -4 41 11.2 12.1 12.3 11.8 11.2 -- 1.40 21:58 kosmos 375( 1009) -78 77 11.5 11.5 12.0 11.4 11.4 -- 0.94 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:00 61 48 11 247 (WSW) 147 ptly cldy none 17:00 57 48 11 232 (SW) mstly clr none 18:00 54 50 8 205 (SSW) mstly clr none 19:00 52 51 2 238 (WSW) mstly clr humid 20:00 52 47 2 199 (SSW) ptly cldy humid 21:00 52 45 6 183 (S) ptly cldy none 22:00 53 47 9 204 (SSW) mstly clr none 23:00 51 46 5 182 (S) mstly clr humid 00:00 51 48 10 166 (SSE) clear humid 01:00 51 48 4 164 (SSE) clear humid 02:00 50 47 12 173 (S) clear humid 03:00 49 48 13 152 (SSE) clear humid 04:00 51 48 11 183 (S) clear humid 05:00 50 47 9 182 (S) clear humid 06:00 48 47 10 179 (S) clear humid 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