Apache Point Observatory 3.5m Telescope Night Log Sunday, March 22, 2026 PROG PI ASTRONOMER OBSERVER(S) -------------------------------------------------------------------- OU01 G.Jewett G.Jewett JH06 C.Lisse C.Lisse, C.Ingebretsen ON-SKY PROG INSTRUMENT START FINISH -------------------------------------------------------------------- OU01 ARCTIC --:-- --:-- JH06 ARCTIC 02:00 03:00 JH06 ECHELLE 03:00 03:45 JH06 ARCTIC 03:45 04:20 JH06 KOSMOS 04:20 06:29 PROG SCHEDULED WEATH EQUIP OBS NOT USED I/ROW/DTN START FINISH D B D B D B D B ----------------------------------------------------------------- OU01/R 19:25 01:10 1.3 4.5 0 0 0.0 0.0 0 0 JH06/R 01:10 06:54 0.8 0 0 0 4.9 0.0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: J.Dembicky Clouds kept us closed at the start of the night. I didn't see precipitation on the radar but the clouds were rather gray. Dust spiked at around 20:40. I had the fans on and turned them off at this point. Dome counts went up on the next update, but not too high (4k inside, 17K outside). I opened around 01:55. Elevated dust but below the 6000 cts limit with low humidity. Fans configured in reverse mode. Dust was elevated for most of the 2nd half, although it did drop below 3K for a while but then went back up. Dust counts in the dome were around 4300 max. No telescope issues tonight. Dataq did freeze during the 2nd half tonight at some point. ------- 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 -------------------------------------------------------------------------- 02:17 arctic -23( 696) -28 73 9.0 11.2 13.6 10.9 10.3 SDSS_r 2.60 02:19 NA2gdr 37998(37998) -30 73 9.3 11.0 13.4 10.7 9.8 clear 3.00 03:11 ecamera 259( -104) 40 57 13.4 11.4 12.8 11.4 12.5 clear 1.22 03:52 arctic 346( 1096) 21 62 13.8 11.7 12.8 11.7 12.7 SDSS_r 0.89 03:54 NA2gdr 37109(37109) 20 62 13.8 11.7 12.8 11.6 12.7 clear 1.09 04:47 kosmos 475( 1135) -8 63 13.7 11.9 12.9 12.1 12.9 -- 0.88 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:00 68 18 8 263 (W) 469 mstly cldy none 17:00 65 17 1 251 (WSW) 358 mstly cldy none 18:00 65 15 10 317 (NW) 436 mstly cldy none 19:00 63 14 6 324 (NW) 416 mstly cldy none 20:00 62 12 5 299 (WNW) 428 mstly cldy dust 21:00 56 23 20 67 (ENE) 20442 ptly cldy dust 22:00 52 26 19 73 (ENE) 14775 ptly cldy dust 23:00 49 25 14 68 (ENE) 9687 mstly cldy dust 00:00 49 22 11 67 (ENE) 7896 mstly cldy dust 01:00 51 20 5 95 (E) 5218 ptly cldy dust 02:00 48 19 8 88 (E) 4324 mstly clr dust 03:00 56 16 2 163 (SSE) 3723 mstly clr none 04:00 57 13 5 255 (WSW) 2794 mstly clr none 05:00 56 15 9 233 (SW) 4495 mstly clr dust 06:00 54 17 8 232 (SW) 4331 mstly clr dust 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: 3.1.8