KECK OBSERVATORY CALENDAR FOR 2021 -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 2021 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 SAT MAY 01 18 55 19 35 20 03 23 56 04 35 05 03 05 42 10 23 14 20 18 56 8.5 3.9 45 1947-2435 >90 SUN MAY 02 18 56 19 36 20 03 00 48 04 34 05 02 05 42 10 27 14 24 18 59 8.5 4.8 55 2051-2245 >90 MON MAY 03 18 56 19 36 20 04 01 34 04 34 05 01 05 41 10 31 14 28 19 03 8.5 5.5 64 2145-1916 >90 TUE MAY 04 18 56 19 36 20 04 02 15 04 33 05 01 05 41 10 35 14 32 19 06 8.5 6.2 72 2235-1501 >90 WED MAY 05 18 57 19 37 20 05 02 52 14 18 04 32 05 00 05 40 10 40 14 36 19 09 8.4 6.8 80 2322-1015 >90 THU MAY 06 18 57 19 37 20 05 03 27 15 09 04 31 04 59 05 40 10 44 14 40 19 12 8.4 7.4 87 0007-0512 >90 FRI MAY 07 18 58 19 38 20 06 03 59 15 58 04 31 04 59 05 39 10 49 14 44 19 16 8.4 7.9 93 0050-0004 >90 SAT MAY 08 18 58 19 38 20 06 04 32 16 47 04 30 04 58 05 39 10 53 14 48 19 19 8.4 8.4 100 0133 0500 >90 SUN MAY 09 18 58 19 39 20 07 05 05 17 35 04 29 04 58 05 38 10 58 14 52 19 22 8.4 8.4 100 0216 0950 >90 MON MAY 10 18 59 19 39 20 08 05 40 18 25 04 29 04 57 05 38 11 03 14 56 19 25 8.3 8.3 100 0300 1417 >90 TUE MAY 11 18 59 19 40 20 08 06 18 19 15 04 28 04 57 05 37 11 07 15 00 19 28 8.3 8.3 100 0346 1812 >90 WED MAY 12 19 00 19 40 20 09 20 07 04 28 04 56 05 37 11 12 15 04 19 32 8.3 8.3 100 0434 2123 >90 THU MAY 13 19 00 19 41 20 09 21 00 04 27 04 55 05 36 11 16 15 08 19 35 8.3 7.4 89 0524 2341 >90 FRI MAY 14 19 00 19 41 20 10 21 53 04 26 04 55 05 36 11 21 15 12 19 38 8.3 6.6 79 0616 2456 >90 SAT MAY 15 19 01 19 42 20 10 22 44 04 26 04 55 05 35 11 25 15 15 19 42 8.3 5.7 68 0709 2501 >90 SUN MAY 16 19 01 19 42 20 11 23 34 04 25 04 54 05 35 11 30 15 19 19 45 8.2 4.8 58 0803 2352 >90 MON MAY 17 19 02 19 43 20 12 00 20 04 25 04 54 05 35 11 35 15 23 19 49 8.2 4.1 49 0857 2123 89 TUE MAY 18 19 02 19 43 20 12 01 04 04 24 04 53 05 34 11 39 15 27 19 52 8.2 3.3 40 0949 1800 79 WED MAY 19 19 03 19 44 20 13 01 45 04 24 04 53 05 34 11 44 15 31 19 56 8.2 2.7 32 1040 1330 69 THU MAY 20 19 03 19 44 20 13 02 25 04 23 04 52 05 34 11 48 15 35 19 59 8.2 2.0 24 1132 0809 60 FRI MAY 21 19 03 19 45 20 14 14 11 03 04 04 23 04 52 05 33 11 52 15 39 20 03 8.1 1.3 16 1223 0209 51 SAT MAY 22 19 04 19 45 20 14 15 10 03 45 04 23 04 52 05 33 11 56 15 43 20 07 8.1 0.6 7 1316-0411 43 SUN MAY 23 19 04 19 46 20 15 16 11 04 28 04 22 04 51 05 33 12 01 15 47 20 10 8.1 0.0 0 1411-1030 38 MON MAY 24 19 05 19 46 20 15 17 15 05 16 04 22 04 51 05 33 12 05 15 51 20 14 8.1 0.0 0 1509-1619 38 TUE MAY 25 19 05 19 47 20 16 18 22 06 09 04 21 04 51 05 32 12 10 15 55 20 17 8.1 0.0 0 1611-2109 41 WED MAY 26 19 06 19 47 20 17 19 30 04 21 04 50 05 32 12 15 15 59 20 21 8.1 0.0 0 1716-2432 48 THU MAY 27 19 06 19 48 20 17 20 38 04 21 04 50 05 32 12 19 16 03 20 24 8.1 0.4 4 1823-2609 57 FRI MAY 28 19 06 19 48 20 18 21 42 04 20 04 50 05 32 12 24 16 07 20 27 8.0 1.4 17 1928-2554 67 SAT MAY 29 19 07 19 49 20 18 22 39 04 20 04 50 05 32 12 28 16 11 20 31 8.0 2.4 29 2031-2354 77 SUN MAY 30 19 07 19 49 20 19 23 30 04 20 04 49 05 31 12 33 16 15 20 35 8.0 3.2 39 2128-2036 87 MON MAY 31 19 08 19 50 20 19 00 13 04 20 04 49 05 31 12 37 16 19 20 39 8.0 3.9 48 2222-1629 >90 ONE LINE REFERS TO EVENING DATE LAST QUARTER May 03 19:50 UT AND FOLLOWING MORNING. NEW MOON May 11 18:59 UT All dates and times are zone HST FIRST QUARTER May 19 19:13 UT in upper table (except sid time). FULL MOON May 26 11:14 UT