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 THU APR 01 18 46 19 24 19 50 23 03 05 02 05 28 06 06 08 11 12 22 17 25 9.2 3.2 34 1706-2332 82 FRI APR 02 18 46 19 24 19 50 00 07 05 01 05 27 06 05 08 15 12 26 17 28 9.2 4.3 46 1808-2523 >90 SAT APR 03 18 47 19 24 19 51 01 07 05 00 05 26 06 04 08 20 12 30 17 31 9.1 5.3 57 1910-2533 >90 SUN APR 04 18 47 19 25 19 51 02 02 04 59 05 25 06 03 08 24 12 34 17 34 9.1 6.2 67 2008-2414 >90 MON APR 05 18 47 19 25 19 51 02 51 04 58 05 24 06 02 08 28 12 38 17 37 9.1 7.0 76 2104-2139 >90 TUE APR 06 18 47 19 25 19 52 03 34 14 34 04 57 05 23 06 01 08 33 12 42 17 39 9.1 7.7 84 2156-1803 >90 WED APR 07 18 48 19 26 19 52 04 14 15 29 04 56 05 22 06 00 08 37 12 46 17 42 9.1 8.4 92 2245-1344 >90 THU APR 08 18 48 19 26 19 52 04 50 16 21 04 55 05 21 06 00 08 41 12 50 17 45 9.0 9.0 99 2331-0856 >90 FRI APR 09 18 48 19 26 19 53 05 24 17 12 04 54 05 20 05 59 08 46 12 54 17 48 9.0 9.0 100 0015-0353 >90 SAT APR 10 18 48 19 27 19 53 05 57 18 01 04 53 05 20 05 58 08 50 12 57 17 51 9.0 9.0 100 0059 0114 >90 SUN APR 11 18 49 19 27 19 53 06 30 18 50 04 52 05 19 05 57 08 54 13 01 17 54 9.0 9.0 100 0142 0616 >90 MON APR 12 18 49 19 27 19 54 19 39 04 51 05 18 05 56 08 59 13 05 17 57 9.0 9.0 100 0225 1101 >90 TUE APR 13 18 49 19 28 19 54 20 29 04 50 05 17 05 55 09 03 13 09 18 00 8.9 8.3 93 0310 1522 >90 WED APR 14 18 50 19 28 19 55 21 20 04 50 05 16 05 55 09 08 13 13 18 04 8.9 7.5 84 0356 1906 >90 THU APR 15 18 50 19 29 19 55 22 12 04 49 05 15 05 54 09 11 13 17 18 07 8.9 6.6 74 0445 2205 >90 FRI APR 16 18 50 19 29 19 56 23 05 04 48 05 14 05 53 09 16 13 21 18 10 8.9 5.7 64 0536 2408 >90 SAT APR 17 18 51 19 29 19 56 23 57 04 47 05 14 05 52 09 20 13 25 18 13 8.9 4.8 54 0628 2507 >90 SUN APR 18 18 51 19 30 19 56 00 48 04 46 05 13 05 51 09 24 13 29 18 16 8.8 4.0 44 0723 2450 83 MON APR 19 18 51 19 30 19 57 01 38 04 45 05 12 05 51 09 29 13 33 18 19 8.8 3.1 35 0817 2323 73 TUE APR 20 18 52 19 30 19 57 02 24 04 44 05 11 05 50 09 33 13 37 18 22 8.8 2.3 26 0912 2038 62 WED APR 21 18 52 19 31 19 58 03 08 04 43 05 10 05 49 09 38 13 41 18 25 8.7 1.6 18 1006 1641 51 THU APR 22 18 52 19 31 19 58 14 27 03 50 04 42 05 09 05 49 09 42 13 45 18 28 8.7 0.9 9 1059 1140 41 FRI APR 23 18 53 19 32 19 59 15 26 04 31 04 42 05 09 05 48 09 47 13 49 18 31 8.7 0.2 2 1153 0550 31 SAT APR 24 18 53 19 32 19 59 16 27 05 12 04 41 05 08 05 47 09 51 13 53 18 34 8.7 0.0 0 1246-0033 26 SUN APR 25 18 53 19 32 20 00 17 29 05 55 04 40 05 07 05 46 09 56 13 57 18 37 8.7 0.0 0 1342-0703 27 MON APR 26 18 54 19 33 20 00 18 32 06 41 04 39 05 06 05 46 10 00 14 01 18 40 8.7 0.0 0 1439-1315 34 TUE APR 27 18 54 19 33 20 01 19 38 04 38 05 06 05 45 10 05 14 04 18 43 8.6 0.0 0 1539-1839 45 WED APR 28 18 54 19 34 20 01 20 46 04 37 05 05 05 44 10 09 14 08 18 46 8.6 0.8 8 1642-2246 57 THU APR 29 18 55 19 34 20 02 21 53 04 37 05 04 05 44 10 14 14 12 18 50 8.6 1.9 21 1746-2518 69 FRI APR 30 18 55 19 35 20 02 22 57 04 36 05 03 05 43 10 18 14 16 18 53 8.6 2.9 34 1850-2559 81 ONE LINE REFERS TO EVENING DATE LAST QUARTER Apr 04 10:03 UT AND FOLLOWING MORNING. NEW MOON Apr 12 02:29 UT All dates and times are zone HST FIRST QUARTER Apr 20 07:00 UT in upper table (except sid time). FULL MOON Apr 27 03:31 UT