Solar eclipse of July 9, 1945 explained

A total solar eclipse occurred at the Moon's ascending node of orbit on Monday, July 9, 1945,[1] with a magnitude of 1.018. 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 4.4 days after perigee (on July 5, 1945, at 4:40 UTC), the Moon's apparent diameter was larger.[2]

The path of totality crossed Oregon, Idaho, and Montana in the northwestern United States, much of central and northeastern Canada, across Greenland and into Scandinavia, the western Soviet Union, and central Asia. A partial eclipse was visible for parts of North America, Europe, North Africa, West Asia, and the Soviet Union. The eclipse was mostly seen on July 9, 1945, except for northeastern Soviet Union, where a partial eclipse was seen on July 10 local time, or starting on July 9, passing midnight and ending on July 10 due to the midnight sun.

Observation

Princeton University sent a team to observe the total eclipse southeast of Malta, Montana. The sun happened to appear from a gap in the clouds around the second contact (the beginning of the total phase). The total phase was not affected by the clouds afterwards, but clouds gradually moved closer to the sun, and blocking the sun during the partial phase after the total phase ended. Nobody saw Baily's beads, prominences or shadow bands there. The team from the Franklin Institute and University of Pennsylvania in Philadelphia went to Wolseley, Saskatchewan, Canada. The weather condition was clear before sunrise, with only some thin clouds near the horizon. The sun passed through a series of clouds after sunrise, and the weather kept good since then. The observation was successful. The team from the Yerkes Observatory, Wisconsin observed the eclipse in Pine River in southwestern Manitoba, Canada. The eclipse occurred on the morning of July 9. The eastern sky was covered with clouds at sunrise. The sun came out from the clouds 25 minutes before totality, and half an hour later the entire sky was covered with clouds again. Because the local duration of totality was only 37 seconds, the team took small- and large-scale images of the corona at the same time in order to completely record the data, to study the characteristics of both the outer and inner corona. Since the eclipse occurred less than 2 months after the end of the European theatre of World War II, only a few Swedish teams, one Danish team and one French team managed to observe it from Scandinavia. Another small Norwegian team and some other teams in the Soviet Union did not make observations successfully due to the clouds. Among them, teams from the Stockholm Observatory, Sweden and Paris Observatory, France observed it in Brattås, Västerbotten, Sweden, and photographed the corona and spectra.[3]

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.[4]

July 9, 1945 Solar Eclipse Times! Event! Time (UTC)
First Penumbral External Contact1945 July 09 at 10:59:59.7 UTC
First Umbral External Contact1945 July 09 at 12:13:56.0 UTC
First Central Line1945 July 09 at 12:14:14.5 UTC
First Umbral Internal Contact1945 July 09 at 12:14:33.1 UTC
Greatest Duration1945 July 09 at 13:25:30.5 UTC
Equatorial Conjunction1945 July 09 at 13:25:35.0 UTC
Greatest Eclipse1945 July 09 at 13:27:45.5 UTC
Ecliptic Conjunction1945 July 09 at 13:35:40.9 UTC
Last Umbral Internal Contact1945 July 09 at 14:41:02.5 UTC
Last Central Line1945 July 09 at 14:41:18.2 UTC
Last Umbral External Contact1945 July 09 at 14:41:34.0 UTC
Last Penumbral External Contact1945 July 09 at 15:55:37.9 UTC
July 9, 1945 Solar Eclipse Parameters! Parameter! Value
Eclipse Magnitude1.01801
Eclipse Obscuration1.03635
Gamma0.73557
Sun Right Ascension07h13m29.9s
Sun Declination+22°22'15.4"
Sun Semi-Diameter15'43.9"
Sun Equatorial Horizontal Parallax08.6"
Moon Right Ascension07h13m34.9s
Moon Declination+23°04'54.4"
Moon Semi-Diameter15'50.6"
Moon Equatorial Horizontal Parallax0°58'08.9"
ΔT27.0 s

Eclipse season

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.

Related eclipses

Eclipses in 1945

Metonic

Tzolkinex

Half-Saros

Tritos

Solar Saros 145

Inex

Triad

Inex series

References

Notes and References

  1. Web site: July 9, 1945 Total Solar Eclipse. timeanddate. 4 August 2024.
  2. Web site: Moon Distances for London, United Kingdom, England. timeanddate. 4 August 2024.
  3. Web site: Xavier M. Jubier. Eclipse totale de Soleil du 9 juillet 1945 depuis le nord-ouest des États-Unis, le centre du Canada ou la Suède (Total Solar Eclipse of 1945 July 9 in northwestern USA, central Canada or Sweden). 26 October 2016. https://web.archive.org/web/20161026164435/http://xjubier.free.fr/site_pages/solar_eclipses/TSE_19450709_pg01.html.
  4. Web site: Total Solar Eclipse of 1945 Jul 09. EclipseWise.com. 4 August 2024.