Solar eclipse of July 20, 1963 explained

A total solar eclipse occurred at the Moon's ascending node of orbit between Saturday, July 20 and Sunday, July 21, 1963,[1] with a magnitude of 1.0224. 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 at least the same size as the Sun's or larger, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with a partial solar eclipse visible over the surrounding region thousands of kilometres wide. Occurring about 4.1 days after perigee (on July 16, 1963, at 19:20 UTC), the Moon's apparent diameter was larger.[2]

Astronomer Charles H. Smiley observed the eclipse from a U.S. Air Force F-104D Starfighter supersonic aircraft that was "racing the Moon's shadow" at 1300mph extending the duration of totality to 4 minutes 3 seconds.[3]

The Moon's apparent diameter was 4.8 arcseconds smaller than the January 25, 1963 annular solar eclipse. This was a total solar eclipse because it occurred in July when the Earth is near aphelion (furthest from the Sun). The Moon's apparent diameter was just over 2.2% larger than the Sun's.

Totality was visible from Hokkaido in Japan and Kuril Islands in Soviet Union (now belonging to Russia) on July 21, and Alaska, and Maine in the United States and also Canada on July 20. A partial eclipse was visible for parts of the eastern Soviet Union, North America, Central America, the Caribbean, far northern Europe, and northern South America.

Observations

Mamoru Mohri, Japanese scientist and former NASDA astronaut, who was 15 years old and living in Hokkaido at the time, said that seeing this total solar eclipse made him want to become a scientist.[4]

Scientists from the Dominion Observatory, University of Oxford, National Research Council Canada and University of Saskatchewan flew a Royal Canadian Air Force aircraft to observe the total eclipse at 30000feet above the Great Slave Lake area. Due to the lack of navigation system in the area, the plane had to fly directly from Ottawa to Fort Simpson and then back to Ottawa, taking about 13 hours in total. On July 20, thin clouds in the Great Slave Lake area expanded to an altitude of 40000feet, so no results were got from optical observations, but the instruments installed on the aircraft still recorded data. In addition, wind speeds of nearly also caused the aircraft to enter the Moon's umbra one minute ahead of schedule, west of the planned location.[5] In addition, scientists from the Royal Astronomical Society of Canada also made radio observations in Grand-Mère, Quebec.[6] [7]

In popular culture

The eclipse was featured in the comic strip Peanuts (July 15–20, 1963), with Linus demonstrating a safe way of observing the eclipse as opposed to looking directly at the eclipse. On the day the eclipse passed over his area, Linus was left helplessly standing in the rain with cloud cover entirely too thick to witness the eclipse.[8]

This particular eclipse event plays an important part in two of Stephen King's novels, Gerald's Game (1992) and Dolores Claiborne (1992).

The eclipse is mentioned in passing in John Updike' s novel Couples (1968) in relation to Piet and Foxy.

The eclipse was featured in the season 3 episode of Mad Men entitled "Seven Twenty Three" (2009, S03E07).[9]

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.[10]

July 20, 1963 Solar Eclipse Times! Event! Time (UTC)
First Penumbral External Contact1963 July 20 at 18:04:48.2 UTC
First Umbral External Contact1963 July 20 at 19:14:15.8 UTC
First Central Line1963 July 20 at 19:14:39.4 UTC
First Umbral Internal Contact1963 July 20 at 19:15:02.9 UTC
Equatorial Conjunction1963 July 20 at 20:29:11.6 UTC
Greatest Duration1963 July 20 at 20:33:37.0 UTC
Greatest Eclipse1963 July 20 at 20:36:13.1 UTC
Ecliptic Conjunction1963 July 20 at 20:43:16.7 UTC
Last Umbral Internal Contact1963 July 20 at 21:57:31.4 UTC
Last Central Line1963 July 20 at 21:57:52.2 UTC
Last Umbral External Contact1963 July 20 at 21:58:13.0 UTC
Last Penumbral External Contact1963 July 20 at 23:07:47.0 UTC
July 20, 1963 Solar Eclipse Parameters! Parameter! Value
Eclipse Magnitude1.02236
Eclipse Obscuration1.04522
Gamma0.65710
Sun Right Ascension07h57m51.3s
Sun Declination+20°41'02.2"
Sun Semi-Diameter15'44.3"
Sun Equatorial Horizontal Parallax08.7"
Moon Right Ascension07h58m07.4s
Moon Declination+21°19'05.7"
Moon Semi-Diameter15'53.9"
Moon Equatorial Horizontal Parallax0°58'20.8"
ΔT34.8 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 1963

Metonic

Tzolkinex

Half-Saros

Tritos

Solar Saros 145

Inex

Triad

Inex series

Notes and References

  1. Web site: July 20, 1963 Total Solar Eclipse. timeanddate. 7 August 2024.
  2. Web site: Moon Distances for London, United Kingdom, England. timeanddate. 7 August 2024.
  3. Smiley . Charles H. . w:Charles Hugh Smiley . February 1964 . Racing the Moon's Shadow on July 20, 1963 . Journal of the Royal Astronomical Society of Canada . 58 . 1 . 10–12 . 1964JRASC..58...10S . The United States Air Force provided an F-104D, a Starfighter made by Lockheed, and Major William A. Cato piloted the plane from Kirkland Air Force Base in New Mexico to Uplands Airport, Ottawa. Since the duration of totality depends on the difference between the speed of the plane and the speed of the moon's shadow, we elected to fly north-west to meet the shadow, then turn and increase speed so that we would reach our maximum speed at 42,000 feet as the shadow overtook us and we continued to climb, attaining 48,000 feet as the shadow left us. .
  4. News: 毛利衛さん宇宙特別授業「宇宙からの贈りもの」. バンクーバー新報. ja. 14 October 2011.
  5. Operation Eclipse-1963 (An Airborne Expedition to Observe the Total Eclipse of the Sun of July 20, 1963). Journal of the Royal Astronomical Society of Canada. 57. 6. 241-252. December 1963. 16 September 2017. https://web.archive.org/web/20170916170608/http://articles.adsabs.harvard.edu/full/1963JRASC..57..241..
  6. Covington, A. E., Kennedy, W. A. G., & Gagnon, H. P. A.. 2700 Mc/s Radio Observations of the Sun During the Total Eclipse of July 20, 1963. Journal of the Royal Astronomical Society of Canada. 60. 215-220. 16 September 2017. https://web.archive.org/web/20170916213144/http://articles.adsabs.harvard.edu/full/1966JRASC..60..215C.
  7. Web site: Past Solar Eclipses & Expeditions. Royal Astronomical Society of Canada. https://web.archive.org/web/20160421201907/http://wwwold.rasc.ca/observing/solareclipses/history.shtml. 21 April 2016.
  8. Web site: Schulz. Charles. 1963-07-20. Peanuts by Charles Schulz for July 20, 1963 GoComics.com. 2021-11-21. GoComics. en.
  9. AMC (2011). Episode 7: Seven Twenty Three (Details tab). Originally retrieved from http://www.amctv.com/shows/mad-men/episodes/season-3/seven-twenty-three. Archived on 2011-04-11 at https://web.archive.org/web/20110411231230/http://www.amctv.com/shows/mad-men/episodes/season-3/seven-twenty-three.
  10. Web site: Total Solar Eclipse of 1963 Jul 20. EclipseWise.com. 7 August 2024.