A total solar eclipse occurred at the Moon's descending node of orbit on Saturday, February 16, 1980,[1] with a magnitude of 1.0434. 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 only about 24 hours before perigee (on February 17, 1980, at 8:50 UTC), the Moon's apparent diameter was larger.[2]
The path of totality crossed parts of Angola, Zaire, Tanzania, Kenya, southern India, Bangladesh, Burma, and China at sunset. The southern part of Mount Kilimanjaro, the highest mountain in Africa, also lay in the path of totality. A partial eclipse was visible for parts of Africa, West Asia, Central Asia, South Asia, and Southeast Asia.
This was the third total solar eclipse visible from mainland India excluding the Andaman and Nicobar Islands in the 20th century. However, most of the path of totality of the solar eclipse of August 21, 1914 in British India now belongs to Pakistan, and the only place within the path of totality of the solar eclipse of June 30, 1954 in India was in the Thar Desert where a total eclipse occurred right before sunset. Therefore, this was actually the first total solar eclipse visible from India with good observation conditions since January 22, 1898.[3]
The Indian Institute of Astrophysics established two camps at Hosur near Hubli and at Jawalagera near Raichur, analyzing the chromospheric and coronal radiation. Observation teams from Czechoslovakia and Yugoslavia also made observations nearby.[4] The Astronomical Institute of Slovak Academy of Sciences also sent a team of 7 people near Jawalagera. The weather condition was good and the team took images of the corona.[5]
Being the first total solar eclipse visible from China after the Cultural Revolution, this eclipse offered much better conditions for observations, compared with the solar eclipse of September 22, 1968, the previous total one visible from China. Although both occurred before sunset with a low solar zenith angle in China, the maximum duration of totality within China was more than 1 minute and 40 seconds for this eclipse, and less than half a minute for the one in 1968.
The Chinese Academy of Sciences held a solar physics conference in Kunming in April 1975, proposing to form a joint observation of the eclipse. In March 1976, a field trip to select the location of observation was conducted. A total of 31 aspects of observations were organized, including solar optical and radio observations, ionosphere, Earth's magnetic field and gravitational field measurements. The meteorological department also studied weather changes during the eclipse. Optical observations in China were mainly conducted at Yingpan Mountain in Ruili County (now Ruili City), Yunnan, while radio observations were at Yunnan Astronomical Observatory in Fenghuang Mountain, Kunming. In addition, Shanghai Scientific and Educational Film Studio made a documentary on the entire process of the observation.[6] [7]
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.