Solar eclipse of April 19, 1958


An annular solar eclipse occurred at the Moon's descending node of orbit on Saturday, April 19, 1958, with a magnitude of 0.9408. 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. An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. Occurring about 2.2 days after apogee, the Moon's apparent diameter was smaller.
Annularity was visible in the Maldives, Nicobar Islands, Burma, Thailand including the capital city Bangkok, Cambodia, Laos, North Vietnam and South Vietnam, China, British Hong Kong, Taiwan, Ryukyu Islands and Japan. Places east of International Date line witnessed the eclipse on April 18. A partial eclipse was visible for most of Asia.
This was the last of four central solar eclipses visible from Bangkok from 1948 to 1958, where it is extremely rare for a large city to witness four central solar eclipses within 10 years.

Observation

Compared with a total solar eclipse, the chromosphere, corona and solar prominence are invisible during an annular eclipse. However, observations of millimeter-wave solar radio can provide data for lower- and mid-layer structure of the chromosphere, which is more valuable during an annular solar eclipse.

China

A joint observation team formed by the Academy of Sciences of the Soviet Union and the Chinese Academy of Sciences conducted 8-millimeter radio observation in Sanya, Hainan Island, China using the equatorial parabolic radio telescope manufactured by the Lebedev Physical Institute and the dual-channel radiometer as a receiver. Radio astronomy started to develop from then in China. Due to the Sino-Soviet split soon after this eclipse, the two countries did not conduct any joint observations of the total solar eclipse of September 22, 1968. On January 23, 1969, the People's Daily published an article reporting the observation of the eclipse in 1968, where it also criticized that the Soviet Union "plundered data of the annular solar eclipse" in 1958, only left China a "worn radio telescope antenna", and later even asked for it back.

Japan

Observation ships were sent to Hachijō-jima, Izu Islands, Japan. Pictures were also taken in Tanegashima, Osumi Islands, and luminosity, air pressure, temperature, humidity, water temperature of the storage tank, ground temperature, wind direction, wind speed and other data were recorded every 10 minutes.

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 Contact1958 April 19 at 00:24:41.6 UTC
First Umbral External Contact1958 April 19 at 01:30:53.9 UTC
First Central Line1958 April 19 at 01:33:33.8 UTC
First Umbral Internal Contact1958 April 19 at 01:36:14.1 UTC
First Penumbral Internal Contact1958 April 19 at 02:47:56.9 UTC
Ecliptic Conjunction1958 April 19 at 03:23:59.6 UTC
Greatest Eclipse1958 April 19 at 03:27:16.7 UTC
Greatest Duration1958 April 19 at 03:33:53.0 UTC
Equatorial Conjunction1958 April 19 at 03:36:02.5 UTC
Last Penumbral Internal Contact1958 April 19 at 04:06:22.2 UTC
Last Umbral Internal Contact1958 April 19 at 05:18:13.8 UTC
Last Central Line1958 April 19 at 05:20:52.8 UTC
Last Umbral External Contact1958 April 19 at 05:23:31.5 UTC
Last Penumbral External Contact1958 April 19 at 06:29:44.7 UTC

ParameterValue
Eclipse Magnitude0.94082
Eclipse Obscuration0.88515
Gamma0.27499
Sun Right Ascension01h46m12.4s
Sun Declination+10°58'10.3"
Sun Semi-Diameter15'55.4"
Sun Equatorial Horizontal Parallax08.8"
Moon Right Ascension01h45m56.6s
Moon Declination+11°12'31.2"
Moon Semi-Diameter14'45.9"
Moon Equatorial Horizontal Parallax0°54'11.2"
ΔT32.3 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. The first and last eclipse in this sequence is separated by one synodic month.
April 4
Ascending node 		April 19
Descending node
May 3
Ascending node
Penumbral lunar eclipse
Lunar Saros 102		Annular solar eclipse
Solar Saros 128		Partial lunar eclipse
Lunar Saros 140

Related eclipses

Eclipses in 1958

Metonic

Tzolkinex

Half-Saros

Tritos

Solar Saros 128

Inex

Triad