|
Sun’s Altitudes at Time of Late Afternoon Prayer for Any Latitude |
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|
Ghâyat irtifâ’ ◦ ' |
Fay-i zawâl m. |
Ghâyat irtifâ’ ◦ ' |
Fay-i zawâl m. |
Ghâyat irtifâ’ ◦ ' |
Fay-i zawâl m. |
Ghâyat irtifâ’ ◦ ' |
Fay-i zawâl m. |
Ghâyat irtifâ’ ◦ ' |
Fay-i zawâl m. |
|---|---|---|---|---|---|---|---|---|---|
| 0.15 | 229.182 | 10.30 | 5.395 | 25.30 | 2.097 | 40.30 | 1171 | 61 | 0.554 |
| 0.30 | 114.589 | 11.00 | 5.145 | 26.00 | 2.050 | 41.00 | 1150 | 62 | 0.532 |
| 0.45 | 76.390 | 11.30 | 4.915 | 26.30 | 2.006 | 41.30 | 1130 | 63 | 0.510 |
| 1.00 | 57.290 | 12.00 | 4.705 | 27.00 | 1.963 | 42.00 | 1111 | 64 | 0.488 |
| 1.15 | 45.829 | 12.30 | 4.511 | 27.30 | 1.921 | 42.30 | 1091 | 65 | 0.466 |
| 1.30 | 38.188 | 13.00 | 4.331 | 28.00 | 1.881 | 43.00 | 1072 | 66 | 0.445 |
| 1.45 | 32.730 | 13.30 | 4.165 | 28.30 | 1.842 | 43.30 | 1054 | 67 | 0.624 |
| 2.00 | 28.636 | 14.00 | 4.011 | 29.00 | 1.804 | 44.00 | 1036 | 68 | 0.404 |
| 2.15 | 25.452 | 14.30 | 3.867 | 29.30 | 1.767 | 44.30 | 1018 | 69 | 0.384 |
| 2.30 | 22.904 | 15.00 | 3.732 | 30.00 | 1.732 | 45.00 | 1000 | 70 | 0.364 |
| 2.45 | 20.819 | 15.30 | 3.606 | 30.30 | 1.698 | 45.30 | 0.983 | 71 | 0.344 |
| 3.00 | 19.081 | 16.00 | 3.487 | 31.00 | 1.664 | 46.00 | 0.966 | 72 | 0.325 |
| 3.15 | 17.611 | 16.30 | 3.376 | 31.30 | 1.632 | 46.30 | 0.949 | 73 | 0.306 |
| 3.30 | 16.350 | 17.00 | 3.271 | 32.00 | 1.600 | 47.00 | 0.933 | 74 | 0.287 |
| 3.45 | 15.257 | 17.30 | 3.172 | 32.30 | 1.570 | 47.30 | 0.916 | 75 | 0.268 |
| 4.00 | 14.301 | 18.00 | 3.078 | 33.00 | 1.540 | 48.00 | 0.900 | 76 | 0.249 |
| 4.15 | 13.457 | 18.30 | 2.989 | 33.30 | 1.511 | 48.30 | 0.885 | 77 | 0.230 |
| 4.30 | 12.706 | 19.00 | 2.904 | 34.00 | 1.483 | 49.00 | 0.869 | 78 | 0.213 |
| 4.45 | 12.035 | 19.30 | 2.824 | 34.30 | 1.455 | 49.30 | 0.854 | 79 | 0.194 |
| 5.00 | 11.430 | 20.00 | 2.747 | 35.00 | 1.428 | 50.00 | 0.839 | 80 | 0.179 |
| 5.30 | 10.385 | 20.30 | 2.675 | 35.30 | 1.402 | 51.00 | 0.830 | 81 | 0.158 |
| 6.00 | 95.14 | 21.00 | 2.605 | 36.00 | 1.376 | 52.00 | 0.781 | 82 | 0.141 |
| 6.30 | 87.77 | 21.30 | 2.539 | 36.30 | 1.351 | 53.00 | 0.754 | 83 | 0.123 |
| 7.00 | 81.44 | 22.00 | 2.475 | 37.00 | 1.327 | 54.00 | 0.727 | 84 | 0.105 |
| 7.30 | 75.96 | 22.30 | 2.414 | 37.30 | 1.303 | 55.00 | 0.700 | 85 | 0.087 |
| 8.00 | 71.15 | 23.00 | 2.356 | 38.00 | 1.280 | 56.00 | 0.675 | 86 | 0.070 |
| 8.30 | 66.91 | 23.30 | 2.300 | 38.30 | 1.257 | 57.00 | 0.649 | 87 | 0.052 |
| 9.00 | 63.94 | 24.00 | 2.246 | 39.00 | 1.235 | 58.00 | 0.625 | 88 | 0.035 |
| 9.30 | 59.76 | 24.30 | 2.194 | 39.30 | 1.213 | 59.00 | 0.601 | 89 | 0.017 |
| 10.00 | 56.71 | 25.00 | 2.145 | 40.00 | 1.192 | 60.00 | 0.577 | 90 | 0.000 |
For instance, the Sun’s declination on February 2 is
-16.48° in Istanbul; hence, ghâyat irtifâ’ (point of solar culmination, the
Sun’s maximum altitude) is -16.48° +49° = 32.12°; fay-i zawâl (the shortest
shadow) of a one-metre-long perpendicular rod is 1.58m.; and the length of its
late-afternoon shadow is 2.58m.; and the Sun’s late-afternoon altitude is
21.20°. The fadli-dâir (temporal value of the arc of complement of the Sun’s
true altitude) is 2 hours and 41 minutes, which will be found by using a
calculator. Thereby the time of late afternoon will be found to be 9.42 hours,
adhânî, and 3.09 hours, in standard time, since the equation of time is -13.39;
(please see Appendix IV.) A method to be used in the absence of the chart above
is to get a privileg calculator, touch the buttons for the computation:
90-32.12 ◦ﻭﻭﻭ→ = tan + 1 =
arc tan MS 90-MR = ◦ﻭﻭﻭ→ and find the Sun’s altitude at the time of ’asr-i awwal (the earlier time of late afternoon) to be 21.08°. There is yet another method: The Rub-i-dâira (quadrant). Its khayt, (thread that represents the daily rotation,) is brought over the number representing the ghâyat irtifâ’; the number on the arc of zill-i-mebsût and crossed by the khayt shows the length of the shortest shadow termed fay-i-zawâl.