An annular solar eclipse occurred at the Moon's descending node of orbit on Wednesday, April 19, 1939,[1] with a magnitude of 0.9731. 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. Occurring about 6.3 days after apogee (on April 13, 1939, at 9:10 UTC), the Moon's apparent diameter was smaller.[2]
This annular eclipse is notable in that the path of annularity passed over the North Pole. Land covered in the path include part of Alaska, Canada, and Franz Josef Land, Ushakov Island and Vize Island in the Soviet Union (today's Russia). A partial eclipse was visible for parts of North America and Western Europe. This was umbral eclipse number 56 out of 57 in Solar Saros 118, this is the last central solar eclipse, and the penultimate umbral eclipse, with the last (ultimate) one in 1957.
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.[3]
| First Penumbral External Contact | 1939 April 19 at 14:26:23.5 UTC | |
| First Umbral External Contact | 1939 April 19 at 16:04:52.6 UTC | |
| First Central Line | 1939 April 19 at 16:07:51.0 UTC | |
| Greatest Duration | 1939 April 19 at 16:07:51.0 UTC | |
| First Umbral Internal Contact | 1939 April 19 at 16:11:02.6 UTC | |
| Ecliptic Conjunction | 1939 April 19 at 16:35:25.0 UTC | |
| Greatest Eclipse | 1939 April 19 at 16:45:53.4 UTC | |
| Equatorial Conjunction | 1939 April 19 at 17:14:29.6 UTC | |
| Last Umbral Internal Contact | 1939 April 19 at 17:20:26.2 UTC | |
| Last Central Line | 1939 April 19 at 17:23:34.9 UTC | |
| Last Umbral External Contact | 1939 April 19 at 17:26:30.4 UTC | |
| Last Penumbral External Contact | 1939 April 19 at 19:05:03.9 UTC |
| Eclipse Magnitude | 0.97308 | |
| Eclipse Obscuration | 0.94689 | |
| Gamma | 0.93880 | |
| Sun Right Ascension | 01h46m48.0s | |
| Sun Declination | +11°01'35.5" | |
| Sun Semi-Diameter | 15'55.2" | |
| Sun Equatorial Horizontal Parallax | 08.8" | |
| Moon Right Ascension | 01h45m51.4s | |
| Moon Declination | +11°52'43.4" | |
| Moon Semi-Diameter | 15'25.0" | |
| Moon Equatorial Horizontal Parallax | 0°56'34.8" | |
| ΔT | 24.1 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.