Solar eclipse of April 28, 1930


A total solar eclipse occurred at the Moon's ascending node of orbit on Monday, April 28, 1930, with a magnitude of 1.0003. It was a hybrid event, with only a fraction of its path as total, and longer sections at the start and end as an annular eclipse. 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. The Moon's apparent diameter was near the average diameter because it occurred 7.2 days after apogee and 6 days before perigee.
Annularity was first visible in the eastern Pacific Ocean, then totality from California, Nevada, Oregon, Idaho and Montana, with annularity continuing northeast across the remainder of Montana and into central and eastern Canada and northern Labrador of the Dominion of Newfoundland. A partial eclipse was visible for parts of Hawaii, North America, and the northern Soviet Union.

Observations

During a hybrid solar eclipse, the apex of the Moon's umbral cone was very close to the Earth's surface, and the magnitude was very large. The edges of the Moon and the Sun were very close to each other as seen from the Earth in both the total and annular portion of the path. A series of Baily's beads on the lunar limb provided an excellent opportunity to measure the size and shape of the Earth, as well as the mountains and valleys on the lunar limb. Scientists recorded the precise time of each phase of the eclipse in Camptonville, California. Because the duration of totality was just more than 1 second, the photographic film needed to be inserted quickly after the start of totality. In addition, scientists recorded audio images with a long-wave receiver on an aircraft at the Mare Island Naval Shipyard. Each image had a time accurate to 1/5 second.
Prior to it, the hybrid solar eclipse of April 17, 1912, also belonging to Solar Saros 137, also occurred with a magnitude close to 1. Observations were made near Paris, France. Similar observations were also made during the annular solar eclipses of May 9, 1948 in Rebun Island, Japan and May 20, 1966 in Greece and Turkey, also belonging to the same solar Saros cycle.

Eclipse details

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.
EventTime
First Penumbral External Contact1930 April 28 at 16:20:27.5 UTC
First Umbral External Contact1930 April 28 at 17:25:43.5 UTC
First Central Line1930 April 28 at 17:26:14.8 UTC
Greatest Duration1930 April 28 at 17:26:14.8 UTC
First Umbral Internal Contact1930 April 28 at 17:26:46.1 UTC
Greatest Eclipse1930 April 28 at 19:03:34.0 UTC
Ecliptic Conjunction1930 April 28 at 19:08:43.9 UTC
Equatorial Conjunction1930 April 28 at 19:27:27.4 UTC
Last Umbral Internal Contact1930 April 28 at 20:40:09.2 UTC
Last Central Line1930 April 28 at 20:40:37.6 UTC
Last Umbral External Contact1930 April 28 at 20:41:06.0 UTC
Last Penumbral External Contact1930 April 28 at 21:46:24.5 UTC

ParameterValue
Eclipse Magnitude1.00026
Eclipse Obscuration1.00053
Gamma0.47305
Sun Right Ascension02h21m32.7s
Sun Declination+14°06'03.1"
Sun Semi-Diameter15'52.8"
Sun Equatorial Horizontal Parallax08.7"
Moon Right Ascension02h20m46.1s
Moon Declination+14°30'42.8"
Moon Semi-Diameter15'39.8"
Moon Equatorial Horizontal Parallax0°57'29.0"
ΔT24.0 s

Eclipse season

This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months 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.
April 13
Descending node 		April 28
Ascending node
Partial lunar eclipse
Lunar Saros 111		Hybrid solar eclipse
Solar Saros 137

Related eclipses

Eclipses in 1930

Metonic

Tzolkinex

Half-Saros

Tritos

Solar Saros 137

Inex

Triad