Solar eclipse of March 7, 1970


A total solar eclipse occurred at the Moon's ascending node of orbit on Saturday, March 7, 1970, with a magnitude of 1.0414. 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 1.3 days after perigee, this eclipse occurred when the Moon's apparent diameter was larger.
The greatest eclipse occurred over Mexico at 11:38 am CST, with totality lasting 3 minutes and 27.65 seconds. Totality over the U.S. lasted up to 3 minutes and 10 seconds. The media declared Perry as the first municipality in Florida to be in the eclipse direct path.
Inclement weather obstructed the viewing from that location and most of the eclipse path through the remainder of the southern states. There was not an eclipse with a greater duration of totality over the contiguous U.S. until April 8, 2024, a period of 54 years.
Totality was visible across southern Mexico and the Gulf of Mexico, Florida, Georgia, South Carolina, North Carolina, Virginia, Maryland, and Nantucket, Massachusetts in the United States, northeast to the Maritimes of eastern Canada, and northern Miquelon-Langlade in the French overseas collectivity of Saint Pierre and Miquelon. A partial eclipse was visible for parts of Hawaii, North America, Central America, the Caribbean, and northern South America.

Scientific effects

This eclipse slowed a radio transmission of atomic time from North Carolina to Washington, D.C.

Observations

An observation team from the Swiss Federal Observatory observed the total eclipse in Nejapa and Miahuatlán, Mexico. The weather conditions were good at both locations. Miahuatlán offered particularly good observation conditions with an altitude of 1,620 metres above sea level, high air quality and solar zenith angle of 63° at the time of the eclipse. The team took images of the corona and analyzed them with a polarizing filter. Austrian-American physicist Erwin Saxl and American physicist Mildred Allen reported anomalous changes in the period of a torsion pendulum when observing a partial solar eclipse with a magnitude of 0.954 from Harvard, Massachusetts, called the "Saxl Effect".

In popular culture

CBS showed the first color broadcast of a total eclipse.
This eclipse might be referenced in the second episode of the first season of The Mary Tyler Moore Show when a guest of Mary's accidentally exposes a roll of film that Howard Arnell, an ex-boyfriend of Mary's, says, "It's just the pictures I took of the total eclipse of the sun."
The eclipse may be referenced in the 1972 hit popular song “You're So Vain” by Carly Simon, although in context, the lyrics more closely align with a different eclipse two years later.

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 Contact1970 March 7 at 15:04:56.2 UTC
First Umbral External Contact1970 March 7 at 16:04:26.6 UTC
First Central Line1970 March 7 at 16:05:14.2 UTC
First Umbral Internal Contact1970 March 7 at 16:06:01.9 UTC
First Penumbral Internal Contact1970 March 7 at 17:27:53.7 UTC
Greatest Duration1970 March 7 at 17:35:20.9 UTC
Greatest Eclipse1970 March 7 at 17:38:29.7 UTC
Ecliptic Conjunction1970 March 7 at 17:43:07.4 UTC
Last Penumbral Internal Contact1970 March 7 at 17:48:30.7 UTC
Equatorial Conjunction1970 March 7 at 18:03:52.1 UTC
Last Umbral Internal Contact1970 March 7 at 19:10:43.5 UTC
Last Central Line1970 March 7 at 19:11:29.8 UTC
Last Umbral External Contact1970 March 7 at 19:12:16.1 UTC
Last Penumbral External Contact1970 March 7 at 20:11:56.2 UTC

ParameterValue
Eclipse Magnitude1.04145
Eclipse Obscuration1.08461
Gamma0.44728
Sun Right Ascension23h11m11.6s
Sun Declination-05°14'13.6"
Sun Semi-Diameter16'06.8"
Sun Equatorial Horizontal Parallax08.9"
Moon Right Ascension23h10m19.7s
Moon Declination-04°50'27.0"
Moon Semi-Diameter16'31.8"
Moon Equatorial Horizontal Parallax1°00'39.8"
ΔT40.4 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.
February 21
Descending node
March 7
Ascending node
Partial lunar eclipse
Lunar Saros 113		Total solar eclipse
Solar Saros 139

Related eclipses

Eclipses in 1970

Metonic

Tzolkinex

Half-Saros

Tritos

Solar Saros 139

Inex

Triad