Tables according to the ephemerides of Uccle/Ukkel (504752N 0042129E). SR/SS and twilight data for each calendar day can also be consulted on the website of the Royal Observatory of Belgium (https://www.astro.oma.be).
| JAN 2021 | FEB 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 1 | 0706 | 0745 | 1548 | 1627 | 5 | 0637 | 0712 | 1642 | 1717 |
| 6 | 0705 | 0744 | 1554 | 1632 | 10 | 0629 | 0704 | 1651 | 1725 |
| 11 | 0703 | 0741 | 1600 | 1638 | 15 | 0621 | 0655 | 1700 | 1734 |
| 16 | 0700 | 0738 | 1608 | 1645 | 20 | 0611 | 0645 | 1708 | 1742 |
| 21 | 0656 | 0733 | 1616 | 1653 | 25 | 0602 | 0635 | 1717 | 1750 |
| 26 | 0650 | 0727 | 1624 | 1700 | |||||
| 31 | 0644 | 0720 | 1633 | 1708 | |||||
| MAR 2021 | APR 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 1 | 0554 | 0627 | 1724 | 1757 | 5 | 0436 | 0510 | 1822 | 1856 |
| 6 | 0543 | 0616 | 1732 | 1805 | 10 | 0424 | 0459 | 1830 | 1904 |
| 11 | 0532 | 0605 | 1741 | 1814 | 15 | 0413 | 0448 | 1838 | 1913 |
| 16 | 0521 | 0554 | 1749 | 1822 | 20 | 0402 | 0438 | 1846 | 1922 |
| 21 | 0510 | 0543 | 1757 | 1830 | 25 | 0351 | 0428 | 1854 | 1931 |
| 26 | 0459 | 0532 | 1806 | 1839 | 30 | 0341 | 0418 | 1902 | 1940 |
| 31 | 0447 | 0521 | 1814 | 1847 | |||||
| MAY 2021 | JUN 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 5 | 0331 | 0409 | 1910 | 1949 | 4 | 0248 | 0332 | 1950 | 2035 |
| 10 | 0322 | 0401 | 1918 | 1957 | 9 | 0245 | 0330 | 1954 | 2040 |
| 15 | 0313 | 0353 | 1925 | 2006 | 14 | 0243 | 0329 | 1957 | 2043 |
| 20 | 0305 | 0347 | 1932 | 2014 | 19 | 0243 | 0329 | 1959 | 2046 |
| 25 | 0258 | 0341 | 1939 | 2022 | 24 | 0244 | 0330 | 2000 | 2046 |
| 30 | 0252 | 0336 | 1945 | 2029 | 29 | 0246 | 0332 | 2000 | 2045 |
| JUL 2021 | AUG 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 4 | 0250 | 0336 | 1958 | 2043 | 3 | 0333 | 0412 | 1924 | 2003 |
| 9 | 0256 | 0340 | 1955 | 2039 | 8 | 0341 | 0420 | 1916 | 1954 |
| 14 | 0302 | 0345 | 1951 | 2034 | 13 | 0350 | 0427 | 1907 | 1944 |
| 19 | 0309 | 0351 | 1946 | 2028 | 18 | 0359 | 0435 | 1857 | 1933 |
| 24 | 0316 | 0358 | 1939 | 2021 | 23 | 0407 | 0443 | 1847 | 1922 |
| 29 | 0324 | 0405 | 1932 | 2012 | 28 | 0415 | 0450 | 1836 | 1911 |
| SEP 2021 | OCT 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 2 | 0424 | 0458 | 1825 | 1859 | 2 | 0512 | 0545 | 1718 | 1751 |
| 7 | 0432 | 0506 | 1814 | 1848 | 7 | 0520 | 0553 | 1707 | 1740 |
| 12 | 0440 | 0513 | 1803 | 1836 | 12 | 0528 | 0601 | 1656 | 1729 |
| 17 | 0448 | 0521 | 1752 | 1825 | 17 | 0536 | 0609 | 1646 | 1719 |
| 22 | 0456 | 0529 | 1741 | 1813 | 22 | 0544 | 0617 | 1636 | 1709 |
| 27 | 0504 | 0537 | 1729 | 1802 | 27 | 0552 | 0626 | 1626 | 1700 |
| NOV 2021 | DEC 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 1 | 0600 | 0634 | 1617 | 1652 | 1 | 0645 | 0723 | 1540 | 1618 |
| 6 | 0608 | 0643 | 1609 | 1644 | 6 | 0651 | 0729 | 1538 | 1617 |
| 11 | 0616 | 0652 | 1601 | 1637 | 11 | 0656 | 0735 | 1537 | 1616 |
| 16 | 0624 | 0700 | 1554 | 1631 | 16 | 0700 | 0739 | 1537 | 1617 |
| 21 | 0631 | 0708 | 1548 | 1625 | 21 | 0703 | 0742 | 1539 | 1619 |
| 26 | 0638 | 0716 | 1544 | 1621 | 26 | 0705 | 0744 | 1542 | 1622 |
| 31 | 0706 | 0745 | 1547 | 1626 | |||||
Tables according to the ephemerides of Findel, Luxembourg (493734N 0061213E).
| JAN 2021 | FEB 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 1 | 0654 | 0734 | 1544 | 1624 | 5 | 0627 | 0703 | 1636 | 1712 |
| 6 | 0654 | 0733 | 1550 | 1629 | 10 | 0620 | 0655 | 1645 | 1720 |
| 11 | 0652 | 0731 | 1556 | 1635 | 15 | 0612 | 0646 | 1653 | 1728 |
| 16 | 0649 | 0727 | 1603 | 1641 | 20 | 0603 | 0637 | 1702 | 1736 |
| 21 | 0645 | 0723 | 1611 | 1649 | 25 | 0553 | 0627 | 1710 | 1744 |
| 26 | 0640 | 0717 | 1619 | 1656 | |||||
| 31 | 0634 | 0710 | 1628 | 1704 | |||||
| MAR 2021 | APR 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 1 | 0546 | 0619 | 1717 | 1750 | 5 | 0431 | 0505 | 1812 | 1846 |
| 6 | 0536 | 0609 | 1725 | 1758 | 10 | 0420 | 0454 | 1819 | 1854 |
| 11 | 0525 | 0558 | 1733 | 1806 | 15 | 0409 | 0444 | 1827 | 1903 |
| 16 | 0515 | 0548 | 1741 | 1814 | 20 | 0358 | 0434 | 1835 | 1911 |
| 21 | 0504 | 0537 | 1748 | 1822 | 25 | 0348 | 0425 | 1842 | 1919 |
| 26 | 0453 | 0526 | 1756 | 1830 | 30 | 0338 | 0416 | 1850 | 1928 |
| 31 | 0442 | 0516 | 1804 | 1838 | |||||
| MAY 2021 | JUN 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 5 | 0329 | 0407 | 1857 | 1936 | 4 | 0248 | 0333 | 1935 | 2020 |
| 10 | 0320 | 0359 | 1905 | 1944 | 9 | 0245 | 0330 | 1939 | 2024 |
| 15 | 0312 | 0352 | 1912 | 1953 | 14 | 0244 | 0329 | 1942 | 2028 |
| 20 | 0304 | 0346 | 1918 | 2000 | 19 | 0243 | 0329 | 1944 | 2030 |
| 25 | 0258 | 0340 | 1925 | 2007 | 24 | 0245 | 0330 | 1945 | 2031 |
| 30 | 0252 | 0336 | 1930 | 2014 | 29 | 0247 | 0333 | 1944 | 2030 |
| JUL 2021 | AUG 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 4 | 0251 | 0336 | 1943 | 2028 | 3 | 0331 | 0410 | 1911 | 1951 |
| 9 | 0256 | 0340 | 1940 | 2024 | 8 | 0339 | 0417 | 1903 | 1941 |
| 14 | 0302 | 0345 | 1936 | 2020 | 13 | 0347 | 0425 | 1854 | 1932 |
| 19 | 0308 | 0351 | 1932 | 2014 | 18 | 0355 | 0432 | 1845 | 1922 |
| 24 | 0315 | 0357 | 1926 | 2007 | 23 | 0403 | 0439 | 1835 | 1911 |
| 29 | 0323 | 0403 | 1919 | 1959 | 28 | 0411 | 0446 | 1825 | 1900 |
| SEP 2021 | OCT 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 2 | 0419 | 0454 | 1815 | 1849 | 2 | 0505 | 0538 | 1710 | 1743 |
| 7 | 0427 | 0501 | 1804 | 1838 | 7 | 0512 | 0546 | 1659 | 1733 |
| 12 | 0435 | 0508 | 1753 | 1827 | 12 | 0520 | 0553 | 1649 | 1723 |
| 17 | 0442 | 0516 | 1743 | 1816 | 17 | 0527 | 0601 | 1639 | 1713 |
| 22 | 0450 | 0523 | 1732 | 1805 | 22 | 0535 | 0609 | 1629 | 1703 |
| 27 | 0457 | 0531 | 1721 | 1754 | 27 | 0543 | 0617 | 1620 | 1655 |
| NOV 2021 | DEC 2021 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Day | Twilight from | SR | SS | Twilight to | Day | Twilight from | SR | SS | Twilight to |
| 1 | 0550 | 0626 | 1611 | 1646 | 1 | 0633 | 0712 | 1536 | 1615 |
| 6 | 0558 | 0634 | 1603 | 1639 | 6 | 0639 | 0718 | 1534 | 1613 |
| 11 | 0606 | 0642 | 1556 | 1632 | 11 | 0644 | 0724 | 1533 | 1613 |
| 16 | 1613 | 0650 | 1549 | 1626 | 16 | 0648 | 0728 | 1534 | 1613 |
| 21 | 0620 | 0658 | 1544 | 1621 | 21 | 0651 | 0731 | 1536 | 1615 |
| 26 | 0627 | 0705 | 1539 | 1618 | 26 | 0653 | 0733 | 1539 | 1618 |
| 31 | 0654 | 0734 | 1543 | 1622 | |||||