Apache Point Observatory
                      3.5m Telescope Night Log
                      Monday, August 24, 2026

PROG  PI ASTRONOMER      OBSERVER(S) 
--------------------------------------------------------------------
AP01  S.Merkowitz       T.Sutherland,R.McMillan
NM07  E.Serviss         E.Nielsen,E.Serviss  
UV01  R.Squillace       R.Squillace           
UW01  P.Yoachim         D.Meng,Z.Xu           

                         ON-SKY
PROG  INSTRUMENT     START   FINISH
--------------------------------------------------------------------
AP01  APOLLO         19:56   20:45   
NM07  ECHELLE        20:50   01:10
UV01  ARCTIC         01:18   03:58
UW01  KOSMOS         04:12   05:50

   PROG       SCHEDULED      WEATH     EQUIP     OBS     NOT USED
 I/ROW/DTN  START  FINISH   D    B    D    B    D    B    D    B
-----------------------------------------------------------------
AP01/W      19:46  20:46    0   0.2   0    0   0.0  0.8   0    0
NM07/R      20:46  01:10    0    0    0    0   0.0  4.4   0    0
UV01/R      01:10  04:10    0    0    0    0   0.1  2.9   0    0
UW01/R      04:10  06:25    0    0    0    0   2.2  0.0   0    0

note: scheduled times listed include instrument change time

              ------------- ACTIVITY LOG --------------
Observing Specialist: A.Townsend

Held off on opening for a few minutes at the start of the night due to radar just northeast of us. After that we had clouds in and out all night but were able to stay open. Dust was elevated in the middle of the night but never much above 3000 counts in 1-micron. 

Tertiary behaved on instrument changes tonight. 

Echelle continues to exhibit read noise in most if not all exposures at varying levels. 

                    ------- 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 APOLLO     500( 2581)  71  18  21.5 25.1 23.8 25.3 22.3   530  1.70
 20:57 ecamera    293(  479) 173  77  21.9 23.3 22.5 22.7 21.6   ND3  0.74
 01:31 arctic     460( 1437) 179  53  18.7 18.6 19.3 18.3 18.4   SDSS_i  1.12
 04:22 kosmos     350( 1305)   6  63  18.9 18.2 18.8 18.3 18.7   --  0.72

               ------------- WEATHER LOG ----------------

                                   Wind                      Precip.or
     Time   Temp F Dewp F  MPH  Direction    Dust    Sky    Conditions
    ------------------------------------------------------------------
     16:00    76    35      7   256  (WSW)   2891  ptly cldy   none 
     17:00    82    39     13   252  (WSW)   2868  ptly cldy   none 
     18:00    77    36      9   249  (WSW)   2857  ptly cldy   none 
     19:00    74    34      1   231   (SW)   2766  ptly cldy   none 
     20:00    71    34      1    21  (NNE)   2784 mstly clr    none 
     21:00    71    33      2   216   (SW)   2697 mstly clr    none 
     22:00    70    34      6   181    (S)   2802    clear     none 
     23:00    70    34     13   181    (S)   2559    clear     none 
     00:00    66    35     15   138   (SE)   3042    clear     none 
     01:00    66    35     14   158  (SSE)   3103 mstly clr    none 
     02:00    65    35     13   152  (SSE)   3042  ptly cldy   none 
     03:00    67    34     10   181    (S)   2989  ptly cldy   none 
     04:00    66    36     13   181    (S)   2872  ptly cldy   none 
     05:00    66    37      9   190    (S)   2558  ptly cldy   none 
     06:00    65    38      6   190    (S)   2486  ptly cldy   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