June 8, 1937, Total Solar Eclipse Was First of Two 1937 Solar Eclipses

Summary: The Tuesday, June 8, 1937, total solar eclipse was the first of two 1937 solar eclipses, with the second occurring Dec. as an annular solar eclipse.

Tuesday, June 8, 1937, total solar eclipse details; credit: "Eclipse map/figure/table/predictions courtesy of Fred Espenak, NASA/Goddard Space Flight Center, from eclipse.gsfc.nasa.gov," via NASA Eclipse Web Site

The Tuesday, June 8, 1937, total solar eclipse was the first of two 1937 solar eclipses, with the second taking place Thursday, Dec. 2, as an annular solar eclipse.

The June 1937 total solar eclipse favored the wide expanses of the Central and East Pacific Ocean. Three remote outliers of the Solomon Islands' easternmost province, Temotu, defined the path of totality's western end, according to TheSkyLive.com's map. The path began east of Tikopia at the Solomon Islands' easternmost uninhabited island, Fatutaka, and easternmost inhabited island, Anuta. The path's northeastward track next touched the atolls of Funafuti, Nukufetau and Vaitupu in the then-Ellice Islands (British colony of Tuvalu since Jan. 1, 1976, and as Commonwealth sovereign state since Oct. 1, 1978). The path of totality crossed the Equator between the atolls of Enderbury and Kiritimati in the then-Gilbert Islands (British colony of Kiribati since Jan. 1, 1976; part of Republic of Kiribati since July 12, 1979).

The path of totality made landfall on Peru's north-central to northwestern coast. The path angled southeastward to make liftoff in the southeastern Peruvian Amazon's Cusco and Madre de Dios regions.

The June 1937 solar eclipse's partial eclipse widened visibility for its path. The path of partiality reached to and even beyond the North Pacific's Tropic of Cancer and the South Pacific's Tropic of Capricorn, according to retired NASA astrophysicist Fred Espenak's EclipseWise website. Continentally, the path of partiality encompassed southern North America (United States, Mexico, Central America) and stretched beyond Peru in northwestern South America to include westernmost North Brazil, Colombia, Ecuador and Venezuela. Placement at the sunset end of the path of partiality meant less visibility for northwestern and north central Argentina, Bolivia, northern and western central Brazil, northern and central Chile, Guyana and western Paraguay.

Retired NASA (National Aeronautics and Space Administration) astrophysicist Espenak's EclipseWise website notes solar and lunar details of the sun in Taurus the Bull constellation and of the moon's reach of perigee 0.7 days prior to the Tuesday, June 8, 1937, solar eclipse. Lunar perigee (Ancient Greek: περί, perí, “near” + γῆ, gê, “Earth”) took place Tuesday, June 8, at 03:31 Coordinated Universal Time (11:31 p.m. Eastern Daylight Time), at a distance of 358,199 kilometers, according to John Walker's Fourmilab Switzerland website.

The partial solar eclipse begins at the instant of first external contact between the lunar penumbra (shadow's lighter, outer region) and Earth's limb, designated as P1. This first external penumbral contact took place Tuesday, June 8, 1937, at 18:04:29.3 UT (2:04 p.m. Eastern Daylight Time), according to Fred Espenak's eclipse predictions on the NASA Eclipse Web Site.

The total solar eclipse begins at the instant of first external contact between the lunar umbra (shadow's dark center) and Earth's limb, designated as U1. This first external umbral contact occurred at 18:58:39.5 UT (2:58 p.m. EDT).

Totality refers to a total eclipse's maximum phase, which entails complete coverage of the solar disk by the lunar disk. Totality concerns the first and last internal contacts of the lunar umbra with Earth's limb.

Designated as U2, the instant of first internal contact between the umbra and Earth's limb took place at 19:01:46.5 UT (3:01 p.m. EDT). This first internal umbral contact actually represents the second contact overall, as it follows the first external umbral contact (U1).

Greatest eclipse references the instant of closest passage of the lunar shadow cone's axis to Earth's center. The Tuesday, June 8, 1937, total solar eclipse's greatest eclipse happened at 20:40:39.6 UT (4:40 p.m. EDT).

Greatest eclipse occurred in the North Pacific Ocean, southeast of the Hawaiian Islands and west of Central America, at 9 degrees 54.7 minutes north latitude, 130 degrees 31.0 minutes west longitude. The path of totality at greatest eclipse had a width of 249.8 kilometers. The duration at greatest eclipse was 7 minutes 4.0 seconds.

The moon's geocentric coordinates at greatest eclipse were right ascension of 5 hours 6 minutes 6.1 seconds and declination of plus 22 degrees 38 arcminutes 22.1 arcseconds. The sun's geocentric coordinates were right ascension of 5 hours 6 minutes 6.5 seconds and declination of plus 22 degrees 52 arcminutes 6.5 arcseconds.

Designated as U3, the instant of last internal contact between the umbra and Earth's limb occurred at 22:19:33.6 UT (6:19 p.m. EDT). This last internal umbral contact represents the second and last internal umbral contact and the third of the four contacts (two internal, two external) overall between the umbra and Earth's limb.

The total solar eclipse ends at the instant of last external contact between the umbra and Earth's limb, designated as U4. This last external umbral contact constitutes the fourth and last of the four contacts overall between the umbra and Earth's limb. The Tuesday, June 8, 1937, total solar eclipse ended at 22:22:38.9 UT (6:22 p.m. EDT).

Meanwhile, as the June 1937 solar event's total solar eclipse was experiencing internal contacts between the umbra and Earth's limb, the event's partial solar eclipse was progressing to internal penumbral contacts. Only eclipses in which the entire penumbral shadow falls within Earth's disk evince internal penumbral contacts. The instant of first internal contact of the penumbra with Earth's limb, designed as P2, took place at 19:58:22.4 UT (3:58 p.m. EDT). The instant of last internal contact of the penumbra with Earth's limb, designated as P3, occurred at 21:22:56.2 UT (5:22 p.m. EDT).

The partial solar eclipse closes with the instant of last external contact of the lunar penumbra with Earth's limb. For the Tuesday, June 8, 1937, solar eclipse, this last external penumbral contact happened at 23:16:51.5 UT (7:16 p.m. EDT).

The June 1937 solar event's partial eclipse lasted for 5 hours 12 minutes 22.2 seconds, from 18:04:29.3 to 23:16:51.5 UT (2:04 p.m. to 7:16 p.m. EDT). The June 1937 solar event's total eclipse had a duration of 3 hours 23 minutes 59.4 seconds, from 18:58:39.5 to 22:22:38.9 UT (2:58 p.m. to 6:22 p.m. EDT).

Making photoelectric measurements of the solar corona numbered among the studies conducted during the Tuesday, June 8, 1937, total solar eclipse. American astronomer Joel Stebbins (July 30, 1878-March 16, 1966) partnered with American physicist Alfred Edward Whitford (Oct. 22, 1905-March 28, 2002) to continue the coronal photometry that he had conducted during the Saturday, June 8, 1918, total solar eclipse with Swiss-born American-naturalized University of Illinois theoretical physicist Jakob Kunz (Nov. 3, 1874-July 18, 1938).

The Tuesday, June 8, 1937, total solar eclipse occurred as the first of 1937's two solar eclipses. The year's second solar eclipse took place Thursday, Dec. 2, as an annular solar eclipse. The December total solar eclipse also favored the Pacific Ocean but excluded continents for the path of totality.

The takeaways for the Tuesday, June 8, 1937, total solar eclipse are that it was the first of two 1937 solar eclipses; that the path of totality favored the Pacific Ocean and Peru; that the eclipse occasioned continuance of solar photometry commenced by American astronomer Joel Stebbins during the Saturday, June 8, 1918, total solar eclipse; and that the year's second solar eclipse occurred almost six months later as an annular solar eclipse.

paths of totality and of partiality for Tuesday, June 8, 1937, total solar eclipse; "Eclipse map/figure/table/predictions courtesy of Fred Espenak, NASA/Goddard Space Flight Center, from eclipse.gsfc.nasa.gov," via NASA Eclipse Web Site

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Tuesday, June 8, 1937, total solar eclipse details; credit: "Eclipse map/figure/table/predictions courtesy of Fred Espenak (NASA's GSFC)," via NASA Eclipse Web Site (https://eclipse.gsfc.nasa.gov/SEpubs/copyright.html) @ https://eclipse.gsfc.nasa.gov/SEplot/SEplot1901/SE1937Jun08T.GIF

paths of totality and of partiality for Tuesday, June 8, 1937, total solar eclipse; "Eclipse map/figure/table/predictions courtesy of Fred Espenak, NASA/Goddard Space Flight Center, from eclipse.gsfc.nasa.gov," via NASA Eclipse Web Site (https://eclipse.gsfc.nasa.gov/SEpubs/copyright.html) @ https://eclipse.gsfc.nasa.gov/5MCSEmap/1901-2000/1937-06-08.gif

For further information:

Eddy, John A. "Chapter 2: The Masks of the Sun." A New Sun: The Solar Results from Skylab. Edited by Rein Ise. Prepared by George C. Marshall Space Flight Center. Washington DC: National Aeronautics and Space Administration, 1979.
Available @ https://history.nasa.gov/SP-402/ch2.htm

Espenak, Fred. “Moon at Perigee and Apogee: 2001 to 2020 Greenwich Mean Time (GMT).” AstroPixels > Planetary Ephemeris Data > Moon > Perigee and Apogee: 2001-2100.
Available @ http://astropixels.com/ephemeris/moon/moonperap2001.html

Espenak, Fred. "Total Solar Eclipse of 1937 Jun 08." EclipseWise > Solar Eclipses > Solar Eclipse Links > Six Millennium Catalog of Solar Eclipses > Catalog of Solar Eclipses: 1901 to 2000
Available @ http://www.eclipsewise.com/solar/SEprime/1901-2000/SE1937Jun08Tprime.html

Espenak, Fred. "Total Solar Eclipse of 1937 Jun 08." NASA Eclipse Web Site > Solar Eclipses > Solar Eclipses: Past and Future > Five Millennium Catalog of Solar Eclipses > Catalog of Solar Eclipses: 1901 to 2000.
Available @ https://eclipse.gsfc.nasa.gov/SEplot/SEplot1901/SE1937Jun08T.GIF

Gardner, Irvine C. Crusoes of Canton Island: Life on a Tiny Pacific Atoll That Has Flashed Into World Importance." National Geographic Magazine, vol. LXXIII, no. 6 (June 1938): 749-766.

Marriner, Derdriu. "Saturday, June 8, 1918, Total Solar Eclipse Belongs to Saros Cycle 126." Earth and Space News. Wednesday, June 23, 2021.
Available @ https://earth-and-space-news.blogspot.com/2021/06/saturday-june-8-1918-total-solar.html

Marriner, Derdriu. "Total Solar Eclipse June 8, 1918, Was First of Two 1918 Solar Eclipses." Earth and Space News. Wednesday, June 16, 2021.
Available @ https://earth-and-space-news.blogspot.com/2021/06/total-solar-eclipse-june-8-1918-was.html

Stebbins, Joel; and A.K. (Albert Edward) Whitford. "The Brightness and Color of the Solar Corona of June 8, 1937." Publications of the American Astronomical Society, Fifty-Eighth Meeting, vol. 9 (1939): 56-57.
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ http://adsabs.harvard.edu/full/1939PAAS....9...56S

Stebbins, Joel; and A.K. (Albert Edward) Whitford. "The Total Light and Color of the Solar Corona of June 8, 1937." The Astrophysical Journal, vol. 87, no. 3 (April 1938): 225-237.
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ http://adsabs.harvard.edu/full/1938ApJ....87..225S
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ http://adsabs.harvard.edu/pdf/1938ApJ....87..225S

TheSkyLive. "Solar Eclipse of June 8 1937 from Marshall Islands." TheSkyLive > Eclipses > Solar Eclipses > 1930-1939.
Available @ https://theskylive.com/solar-eclipse?id=1937-06-08&cc=MH

Time and Date. "June 8, 1937 Total Solar Eclipse." Time and Date > Sun & Moon > Eclipses.
Available @ https://www.timeanddate.com/eclipse/solar/1937-june-8

Walker, John. "Lunar Perigee and Apogee Calculator." Fourmilab Switzerland > Earth and Moon Viewer and Solar System Explorer.
Available @ https://www.fourmilab.ch/earthview/pacalc.html

Whitford, A.E. (Albert Edward). Joel Stebbins 1878-1966: A Biographical Memoir. Washington DC: National Academy of Sciences, 1978.
Available @ http://nasonline.org/publications/biographical-memoirs/memoir-pdfs/stebbins-joel.pdf