Apache Point Observatory 3.5m Telescope Night Log Monday, October 12, 2026 PROG PI ASTRONOMER OBSERVER(S) -------------------------------------------------------------------- GS02 D.Gies A.Chaturvedi BY02 D.Spencer D.Spencer ON-SKY PROG INSTRUMENT START FINISH -------------------------------------------------------------------- GS02 ECHELLE 18:42 01:05 BY02 ARCTIC 01:10 02:00 BY02 ARCTIC 02:40 06:44 PROG SCHEDULED WEATH EQUIP OBS NOT USED I/ROW/DTN START FINISH D B D B D B D B ----------------------------------------------------------------- GS02/R 18:42 01:10 0 0 0 0 5.6 0.9 0 0 BY02/R 01:10 06:58 0.7 0 0 0 5.1 0.0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: T.Sutherland Opened at 18:30 to start venting. Some clouds here and there but nothing too bad at the start of the night. Arctic LL quad partially recovered by 22:30, and almost fully recovered by the time it was in use for B-half. Only a handful of saturated pixels remained in the LL quad. Clouds were forming right on top of us at the start of b-half and I closed at 2am after being unable to focus arctic. Opened back up at 2:40am due to the clouds clearing, and stayed open the rest of the night. TUI disconnected on obs-A at 3:03am. Reconnected with no problem. ------- 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 -------------------------------------------------------------------------- 18:56 ecamera 374( 116) 12 77 11.9 13.8 13.6 13.8 12.1 ND2 0.87 19:47 ecamera 421( 101) -19 59 11.9 12.3 12.7 12.0 11.8 ND2 1.14 02:57 arctic 496( 1061) -70 26 9.8 9.4 10.0 9.3 9.5 SDSS_g 1.66 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:00 56 45 20 232 (SW) 275 ptly cldy none 17:00 58 46 15 205 (SSW) 407 mstly clr none 18:00 56 44 11 259 (W) 311 mstly clr none 19:00 53 46 12 227 (SW) clear none 20:00 54 46 11 201 (SSW) clear none 21:00 54 45 18 187 (S) clear none 22:00 54 44 23 219 (SW) 432 clear none 23:00 53 45 17 210 (SSW) mstly clr none 00:00 51 45 12 239 (WSW) mstly clr none 01:00 51 43 12 269 (W) mstly cldy none 02:00 50 40 9 263 (W) mstly clr none 03:00 49 38 9 262 (W) 276 mstly clr none 04:00 50 36 15 245 (WSW) 278 mstly clr none 05:00 48 37 9 275 (W) 169 mstly clr none 06:00 48 37 12 267 (W) 204 mstly clr 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