Longest Total Solar Eclipse of 21st Century on July 22, 2009
A total solar eclipse occurred on Wednesday, July 22, 2009, at the Moon’s descending node of its orbit with a magnitude of 1.07991. A solar eclipse happens when the Moon passes between the Earth and the Sun, partially or fully obscuring the Sun’s image from viewers on Earth. When the Moon’s apparent diameter is larger than the Sun’s, it causes a total solar eclipse, turning day into darkness in a narrow path along Earth’s surface while a partial eclipse is visible over a wider surrounding area. This eclipse took place about 5.5 hours after the Moon’s perigee, meaning the Moon was closer to Earth and appeared larger in the sky, enabling the total coverage of the Sun by the Moon.
This event was the longest total solar eclipse of the 21st century, with totality lasting a maximum of 6 minutes and 38.86 seconds, witnessed off the coast of Southeast Asia. The corridor of totality spanned across northern India, eastern Nepal, Bhutan, the northern tip of Myanmar, central China, and the Pacific Ocean, including parts of Japan’s Ryukyu Islands. The eclipse attracted significant tourist and scientific interest across countries such as eastern China, Pakistan, Japan, India, Nepal, and Bhutan. Many major cities along the path experienced totality, including Surat, Vadodara, Bhopal, Varanasi, Patna, and Guwahati in India, as well as Chengdu, Shanghai, Wuhan, and Hangzhou in China. The Chinese government utilized this opportunity for scientific education and dispelling superstitions surrounding eclipses.
In Japan, this was the first eclipse in 46 years, but cloudy skies obstructed clear views for many observers. In Bangladesh, despite rain, thousands witnessed the eclipse lasting about 3 minutes and 44 seconds. The maximum phase occurred over the ocean south of the Bonin Islands, southeast of Japan. Innovative viewing experiences included a flight by China Eastern Airlines that followed the eclipse path for extended observation. The cruise ship Costa Classica also channeled along the centerline of totality to maximize viewing duration.
This eclipse was part of the Saros 136 series, which involves eclipses occurring at the Moon’s descending node. The July 22, 2009 eclipse’s long duration and wide visibility made it a major celestial event, surpassing others of the century, and it held unique significance until eclipses of comparable or longer duration occur in the future, such as one predicted in 2132.