A total solar eclipse occurred at the Moon's ascending node of orbit on Thursday, May 9, 1929,[1] with a magnitude of 1.0562. 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. A total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Occurring about 1.7 days before perigee (on May 10, 1929, at 21:00 UTC), the Moon's apparent diameter was larger.[2]
Totality was visible from Dutch East Indies (today's Indonesia), Federated Malay States (now belonging to Malaysia), Siam (name changed to Thailand later), French Indochina (the part now belonging to Vietnam), Spratly Islands, Philippines, and South Seas Mandate in Japan (the part now belonging to FS Micronesia). A partial eclipse was visible for parts of Southeast Africa, South Asia, Southeast Asia, East Asia, and Australia..
A team of British and German scientists observed the total eclipse in Pattani province in southern Siam. King Rama VII and Queen Rambai Barni also visited the observation camp set up by foreign scientists and observed the eclipse together in Pattani. This was the last time that Siam (Thailand) received a large-scale solar eclipse observation team so far. The other teams Thailand received later, including the American team for the total solar eclipse of June 20, 1955 were much smaller.[3]
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.[4]
| First Penumbral External Contact | 1929 May 09 at 03:32:58.0 UTC | |
| First Umbral External Contact | 1929 May 09 at 04:29:32.5 UTC | |
| First Central Line | 1929 May 09 at 04:30:38.2 UTC | |
| First Umbral Internal Contact | 1929 May 09 at 04:31:43.9 UTC | |
| First Penumbral Internal Contact | 1929 May 09 at 05:32:55.2 UTC | |
| Equatorial Conjunction | 1929 May 09 at 05:58:29.8 UTC | |
| Ecliptic Conjunction | 1929 May 09 at 06:07:34.8 UTC | |
| Greatest Eclipse | 1929 May 09 at 06:10:34.1 UTC | |
| Greatest Duration | 1929 May 09 at 06:17:47.1 UTC | |
| Last Penumbral Internal Contact | 1929 May 09 at 06:48:30.3 UTC | |
| Last Umbral Internal Contact | 1929 May 09 at 07:49:29.9 UTC | |
| Last Central Line | 1929 May 09 at 07:50:37.4 UTC | |
| Last Umbral External Contact | 1929 May 09 at 07:51:44.7 UTC | |
| Last Penumbral External Contact | 1929 May 09 at 08:48:11.5 UTC |
| Eclipse Magnitude | 1.05622 | |
| Eclipse Obscuration | 1.11560 | |
| Gamma | −0.28869 | |
| Sun Right Ascension | 03h02m38.7s | |
| Sun Declination | +17°14'10.1" | |
| Sun Semi-Diameter | 15'50.3" | |
| Sun Equatorial Horizontal Parallax | 08.7" | |
| Moon Right Ascension | 03h03m05.7s | |
| Moon Declination | +16°58'00.8" | |
| Moon Semi-Diameter | 16'27.7" | |
| Moon Equatorial Horizontal Parallax | 1°00'24.9" | |
| ΔT | 24.0 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.