Solar eclipse of February 4, 1981

The Astronomical Society of Tasmania set up 18 observation sites on the northern and southern edges of the path of annularity in Tasmania to measure the diameter of the Sun. However, data were obtained from only one site on the northern and one on the southern edge due to the clouds. The United States Naval Observatory also took images of the partial phase with portable video recorders in Tasmania. Besides, due to the influence of the concave and convex peaks on the edge of the Moon, if the Moon is assumed to be a uniform sphere, the predicted times of each contact of the eclipse were slightly different from the actual times because the predictions assumed the Moon to be a circular body but there are actually mountains and valleys on the lunar limb. The British Astronomical Association observed this eclipse in Tasmania and studied the methods to calculate the time of eclipses more accurately. == 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. == Eclipse season ==

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 1981 • A penumbral lunar eclipse on January 20. • An annular solar eclipse on February 4. • A partial lunar eclipse on July 17. • A total solar eclipse on July 31. Metonic • Preceded by: Solar eclipse of April 18, 1977 • Followed by: Solar eclipse of November 22, 1984 Tzolkinex • Preceded by: Solar eclipse of December 24, 1973 • Followed by: Solar eclipse of March 18, 1988 Half-Saros • Preceded by: Lunar eclipse of January 30, 1972 • Followed by: Lunar eclipse of February 9, 1990 Tritos • Preceded by: Solar eclipse of March 7, 1970 • Followed by: Solar eclipse of January 4, 1992 Solar Saros 140 • Preceded by: Solar eclipse of January 25, 1963 • Followed by: Solar eclipse of February 16, 1999 Inex • Preceded by: Solar eclipse of February 25, 1952 • Followed by: Solar eclipse of January 15, 2010 Triad • Preceded by: Solar eclipse of April 6, 1894 • Followed by: Solar eclipse of December 6, 2067 Solar eclipses of 1979–1982 Saros 140 Metonic series Tritos series Inex series ==Notes==