KECK OBSERVATORY CALENDAR FOR 2025 -ASTRONOMICAL (computed for altitude 4160.0 m) ASTRONOMICAL(18 deg) TWILIGHT/DAWN MOON(midnight) DATE(HST) SUN TWILIGHT ENDS MOON MOON DAWN BEGINS SUN SIDEREAL TIMES NIGHT (18 deg) Zenith 2025 SET RISE SET RISE TWI MID DAWN LENGTH DARK___ RA DEC Dist 12 18 18 12 18 18 h h % h m d m deg MON SEP 01 18 48 19 26 19 53 14 06 01 23 04 52 05 18 05 56 18 18 22 25 03 18 9.0 3.5 38 1816-2853 77 TUE SEP 02 18 47 19 25 19 52 14 59 02 20 04 52 05 18 05 57 18 21 22 29 03 22 9.0 2.5 28 1913-2734 67 WED SEP 03 18 46 19 24 19 51 15 49 03 19 04 52 05 19 05 57 18 24 22 33 03 26 9.0 1.6 17 2009-2443 57 THU SEP 04 18 45 19 23 19 50 16 35 04 18 04 53 05 19 05 57 18 26 22 37 03 31 9.0 0.6 6 2104-2028 46 FRI SEP 05 18 44 19 22 19 49 17 17 05 18 04 53 05 19 05 57 18 29 22 41 03 35 9.1 0.0 0 2157-1503 36 SAT SEP 06 18 43 19 21 19 48 17 57 06 16 04 53 05 19 05 57 18 32 22 45 03 39 9.1 0.0 0 2249-0845 29 SUN SEP 07 18 43 19 21 19 47 18 35 04 54 05 20 05 58 18 35 22 49 03 44 9.1 0.0 0 2341-0153 25 MON SEP 08 18 42 19 20 19 46 19 13 04 54 05 20 05 58 18 38 22 53 03 48 9.1 0.0 0 0033 0509 28 TUE SEP 09 18 41 19 19 19 45 19 53 04 54 05 20 05 58 18 41 22 57 03 52 9.2 0.1 1 0126 1156 37 WED SEP 10 18 40 19 18 19 44 20 35 04 54 05 20 05 58 18 44 23 01 03 56 9.2 0.9 9 0222 1801 47 THU SEP 11 18 39 19 17 19 43 21 21 04 55 05 21 05 59 18 47 23 05 04 01 9.2 1.6 17 0320 2259 59 FRI SEP 12 18 38 19 16 19 42 22 13 04 55 05 21 05 59 18 50 23 09 04 04 9.2 2.5 27 0422 2626 71 SAT SEP 13 18 37 19 15 19 41 23 11 04 55 05 21 05 59 18 53 23 13 04 08 9.2 3.5 37 0525 2805 84 SUN SEP 14 18 36 19 14 19 40 00 13 04 56 05 21 05 59 18 56 23 17 04 13 9.3 4.6 49 0629 2758 >90 MON SEP 15 18 35 19 13 19 39 01 16 14 37 04 56 05 22 05 59 18 59 23 21 04 17 9.3 5.6 60 0729 2604 >90 TUE SEP 16 18 34 19 12 19 38 02 18 15 28 04 56 05 22 06 00 19 02 23 24 04 21 9.3 6.7 71 0826 2244 >90 WED SEP 17 18 33 19 11 19 37 03 17 16 13 04 56 05 22 06 00 19 05 23 28 04 25 9.3 7.7 82 0918 1818 >90 THU SEP 18 18 32 19 10 19 36 04 13 16 53 04 57 05 22 06 00 19 08 23 32 04 30 9.3 8.6 92 1007 1306 >90 FRI SEP 19 18 32 19 09 19 35 05 06 17 28 04 57 05 23 06 00 19 11 23 36 04 34 9.4 9.4 100 1053 0726 >90 SAT SEP 20 18 31 19 08 19 34 05 56 18 01 04 57 05 23 06 00 19 13 23 40 04 38 9.4 9.4 100 1137 0135 >90 SUN SEP 21 18 30 19 07 19 33 06 46 18 33 04 57 05 23 06 01 19 16 23 44 04 42 9.4 9.4 100 1220-0415 >90 MON SEP 22 18 29 19 06 19 32 19 05 04 58 05 23 06 01 19 19 23 48 04 47 9.4 9.4 100 1303-0952 >90 TUE SEP 23 18 28 19 05 19 31 19 38 04 58 05 23 06 01 19 22 23 52 04 51 9.5 9.3 98 1347-1504 >90 WED SEP 24 18 27 19 05 19 30 20 13 04 58 05 24 06 01 19 25 23 56 04 55 9.5 8.7 92 1432-1941 >90 THU SEP 25 18 26 19 04 19 29 20 51 04 58 05 24 06 01 19 28 00 00 04 59 9.5 8.1 85 1519-2333 >90 FRI SEP 26 18 25 19 03 19 28 21 34 04 59 05 24 06 02 19 31 00 04 05 04 9.5 7.4 77 1609-2629 >90 SAT SEP 27 18 24 19 02 19 27 22 21 04 59 05 24 06 02 19 34 00 08 05 08 9.5 6.6 69 1702-2817 >90 SUN SEP 28 18 23 19 01 19 26 23 12 04 59 05 25 06 02 19 37 00 12 05 12 9.6 5.8 60 1756-2850 >90 MON SEP 29 18 23 19 00 19 26 00 07 04 59 05 25 06 02 19 41 00 16 05 16 9.6 4.9 50 1856-2734 >90 TUE SEP 30 18 22 18 59 19 25 01 04 05 00 05 25 06 03 19 44 00 20 05 20 9.6 3.9 41 1947-2544 80 ONE LINE REFERS TO EVENING DATE FULL MOON Sep 07 18:07 UT AND FOLLOWING MORNING. LAST QUARTER Sep 14 10:33 UT All dates and times are zone HST NEW MOON Sep 21 19:51 UT in upper table (except sid time). FIRST QUARTER Sep 29 23:54 UT