The moon passes between the sun and the earth during a total solar eclipse in the northern Indian city of Varanasi July 22, 2009. The longest total solar eclipse of the 21st century began its flight on Wednesday across a narrow path of Asia, where it was expected to darken the skies for millions of people for more than six minutes in some places. (Xinhua/Reuters Photo)

The moon passes between the sun and the earth amid monsoon clouds during a solar eclipse in New Delhi on July 22, 2009. (Xinhua/Reuters Photo)

A partial solar eclipse is seen through a razor wire fence on Combat Operation Outpost (COP) McClain in Logar Province in Afghanistan July 22, 2009. (Xinhua/Reuters Photo)

The longest total solar eclipse of the 21st century began its flight on Wednesday across a narrow path of Asia, where it was expected to darken the skies for millions of people for more than six minutes in some places.