Subject: 3.5m Night Log 20250915 From: mcroom@apo.nmsu.edu Date: Tue, 16 Sep 2025 12:52:15 +0000 (UTC) Apache Point Observatory 3.5m Telescope Night Log Monday, September 15, 2025 PROG PI ASTRONOMER OBSERVER(S) -------------------------------------------------------------------- BY04 M.Joner M.Joner,B.Boizelle,O.Hancock OU04 J.Serna J.Serna ON-SKY PROG INSTRUMENT START FINISH -------------------------------------------------------------------- BY04 ARCTIC 19:17 01:05 OU04 ECHELLE 01:12 01:54 OU04 ECHELLE 03:12 05:24 PROG SCHEDULED WEATH EQUIP OBS NOT USED I/ROW/DTN START FINISH D B D B D B D B ----------------------------------------------------------------- BY04/R 19:17 01:10 0 0 0 0 5.9 0.0 0 0 OU04/R 01:10 06:39 0 1.3 0 0 0.2 4.0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: M.Croom Candace gave on-site support with 3.5m and ARCSAT. Had to restart alcor all-sky camera at the USB connection. First observer took narrowband filter sky flats right at sunset; however, the first 'slew for focus' was at 19:42. Encountered a motion error on that first slew. Commanding axis stop/init cleared the error but a collision immediately occurred at the start of the next slew. This triggered the intermediate level stop button. Releasing that button allowed us to resume in short order. Seeing was good all night, and a few thin clouds were always on the horizon and occasionally skirted across overhead. Humidity was the concern tonight. We had to close shortly after B Half began due to humidity. We were able to re-open, although it was a bit of a guess with since the margins were slim and the outside Optidew was no help. Closed from 01:54 to 03:12, but open otherwise until the observer finished his targets at astro twilight. ------- 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 -------------------------------------------------------------------------- 20:02 arctic 617( 1525) 158 60 13.3 15.1 15.1 14.0 13.6 SDSSr#2 0.57 20:10 arctic 617( 1516) 160 61 13.2 14.9 14.9 13.9 13.5 WA_HA 0.56 21:21 arctic 629( 1466) 272 41 12.9 13.2 13.6 12.5 12.6 WA_HA 0.80 21:37 arctic 394( 1223) 270 38 12.8 13.0 13.4 12.4 12.6 WA_HA 1.30 03:24 ecamera 443( 67) 104 81 12.1 11.3 12.1 11.3 11.8 ND2 0.80 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:00 63 39 9 265 (W) 619 mstly cldy none 17:00 62 40 5 273 (W) 603 mstly cldy none 18:00 60 38 2 255 (WSW) 596 ptly cldy none 19:00 59 45 2 204 (SSW) 616 mstly clr none 20:00 56 46 11 102 (ESE) mstly clr none 21:00 55 48 11 94 (E) mstly clr none 22:00 56 43 17 125 (SE) mstly clr none 23:00 54 46 13 114 (ESE) mstly clr none 00:00 54 46 11 111 (ESE) mstly clr none 01:00 54 47 16 134 (SE) mstly clr humid 02:00 53 49 15 135 (SE) mstly clr humid 03:00 54 46 12 133 (SE) mstly clr none 04:00 54 45 8 174 (S) mstly clr none 05:00 54 46 8 187 (S) 545 mstly clr none 06:00 53 46 7 149 (SSE) 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: 3.1.8