An annular solar eclipse occurred at the Moon's descending node of orbit between Saturday, March 28 and Sunday, March 29, 1903,[1] [2] [3] with a magnitude of 0.9767. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. The Moon's apparent diameter was near the average diameter because it occurred 6.7 days after apogee (on March 22, 1903, at 8:40 UTC) and 7.8 days before perigee (on April 5, 1903, at 18:40 UTC).[4]
Annularity was visible from China (now northwestern China, Mongolia and northeastern China), Russia on March 29 (Sunday), and Northern Canada on March 28 (Saturday). A partial eclipse was visible for parts of Southeast Asia, East Asia, North Asia, Alaska, and Northwestern North America.
Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.[5]
| First Penumbral External Contact | 1903 March 28 at 23:09:08.3 UTC | |
| First Umbral External Contact | 1903 March 29 at 00:33:20.8 UTC | |
| First Central Line | 1903 March 29 at 00:35:13.8 UTC | |
| Greatest Duration | 1903 March 29 at 00:35:13.8 UTC | |
| First Umbral Internal Contact | 1903 March 29 at 00:37:09.4 UTC | |
| Ecliptic Conjunction | 1903 March 29 at 01:26:01.9 UTC | |
| Greatest Eclipse | 1903 March 29 at 01:35:22.9 UTC | |
| Equatorial Conjunction | 1903 March 29 at 02:05:13.3 UTC | |
| Last Umbral Internal Contact | 1903 March 29 at 02:33:17.3 UTC | |
| Last Central Line | 1903 March 29 at 02:35:10.0 UTC | |
| Last Umbral External Contact | 1903 March 29 at 02:37:00.1 UTC | |
| Last Penumbral External Contact | 1903 March 29 at 04:01:17.3 UTC |
| Eclipse Magnitude | 0.97669 | |
| Eclipse Obscuration | 0.95392 | |
| Gamma | 0.84126 | |
| Sun Right Ascension | 00h26m26.0s | |
| Sun Declination | +02°51'27.8" | |
| Sun Semi-Diameter | 16'01.0" | |
| Sun Equatorial Horizontal Parallax | 08.8" | |
| Moon Right Ascension | 00h25m28.1s | |
| Moon Declination | +03°37'00.1" | |
| Moon Semi-Diameter | 15'30.9" | |
| Moon Equatorial Horizontal Parallax | 0°56'56.5" | |
| ΔT | 1.5 s |
See also: Eclipse cycle. This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a fortnight.