By Suman Kandel
Stunning total solar eclipse was visible from North America on 21 August. Americans had to wait for decades for such an eclipse. It is reported that such eclipse in 2017, was only seen in 1979. The sun was totally blocked by the moon visible for more than one and half hour from 14 states of USA.
Solar eclipse path (source: http://griffithobservatory.org/events/Solar_Eclipse_August_2017.html)
As the weather was also good all over the region, the eclipse was clearly visible. The once-in-a-lifetime experience was largely celebrated, people were found gathering at different places to witness the eclipse. The eclipse was popular in the social media. There were more than 6 million tweets and 3 million views in NASA’s Facebook live stream.
(Image: Animation of the shadow created by August 21 eclipse)
Solar eclipse occurs when full moon moving between earth and the sun blocks some or all of the light from the sun on reaching earth. When moon eclipse the sun, it casts two types of shadows on earth. Umbra is the region of darker shadow and Penumbra of larger shadow. Solar eclipse is of four types: Total Eclipse (moon completely blocks the light from the sun), Partial Eclipse (moon partially blocks the sun), Annular Eclipse (sun and moon are exactly in line with earth) and Hybrid Eclipse (combination of total and annular eclipse-very rare)
History of Solar eclipses
In the 20th century (1901-2000) there were 228 solar eclipses of which 71 were total, 78 were partial, 73 were annular and 6 were hybrid.
Of the eclipses in the 20th century, the eclipse on 29 May 1919 was the remarkable eclipse in the history which was photographed by Arthur Eddington and helped to verify Einstein’s Theory of General Relativity.
Solar eclipses in 21st century
During the 21st century, there will be 224 solar eclipses of which 68 will be total, 77 will be partial, 72 will be annular and 7 will be hybrid eclipses.
(Predictions given here are by Fred Espenak of NASA’s Goddard Space Flight Center)
Sources: www.nationalgeographic.com , nytimes.com