Subject: 3.5m Night Log 20250720 From: cgray@apo.nmsu.edu Date: Mon, 21 Jul 2025 10:07:26 +0000 (UTC) Apache Point Observatory 3.5m Telescope Night Log Sunday, July 20, 2025 PROG PI ASTRONOMER OBSERVER(S) -------------------------------------------------------------------- UW02 B.Benda B.Benda CU02 Y.Notsu Y.Notsu ON-SKY PROG INSTRUMENT START FINISH -------------------------------------------------------------------- UW02 ECHELLE 21:53 22:33 CU02 ARCTIC --:-- --:-- PROG SCHEDULED WEATH EQUIP OBS NOT USED I/ROW/DTN START FINISH D B D B D B D B ----------------------------------------------------------------- UW02/R 20:18 01:10 4.2 0 0 0 0.7 0.0 0 0 CU02/R 01:10 06:01 1.3 3.5 0 0 0 0 0 0 note: scheduled times listed include instrument change time ------------- ACTIVITY LOG -------------- Observing Specialist: C.Gray dataq needed restart We had two motion errors in altitude, both while coming down. One at 15 deg during check out and another at 67 deg while on sky (21:53). The weather was quite frustrating. There were storms popping up everywhere but directly overhead. Eventually, I realized we were at the center of a large rotating system and the "sucker hole" might last a while. I opened around 10 pm and we were able to get one exposure before everything closed in around us. It was lucky I closed when I did, as less then 10 min later the dust spiked to 75k! The echelle IOL was down to 10 in both red and blue but UW02 said the data was useable! So yay! Storms kept coming up and, while we were in dark green radar, the rain sensor never went off and, as far as I can tell, it never rained. By 4 am we were still under solid radar with no hopes of it going away before dawn so I called it. ------- 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 -------------------------------------------------------------------------- 21:00 ecamera 274( 318) 225 49 18.3 19.9 19.7 19.6 18.0 clear 1.71 ------------- WEATHER LOG ---------------- Wind Precip.or Time Temp F Dewp F MPH Direction Dust Sky Conditions ------------------------------------------------------------------ 16:00 72 48 12 183 (S) 1754 ptly cldy none 17:00 76 49 11 195 (SSW) 1672 ptly cldy none 18:00 72 44 15 234 (SW) 1446 ptly cldy none 19:00 68 45 16 211 (SSW) 1597 ptly cldy none 20:00 67 46 14 221 (SW) 1547 mstly clr none 21:00 65 45 10 200 (SSW) 1458 mstly clr none 22:00 65 46 9 212 (SSW) 1578 mstly cldy dust 23:00 61 49 15 194 (SSW) 77523 mstly cldy dust 00:00 59 49 13 143 (SE) 16679 cloudy dust 01:00 57 47 18 154 (SSE) cloudy humid 02:00 57 46 12 168 (SSE) 2129 cloudy dust 03:00 56 45 12 159 (SSE) 1197 cloudy none 04:00 57 43 15 200 (SSW) 610 cloudy 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