Century's longest solar eclipse generates business, scientific interest

The longest total solar eclipse of the century will take place on 22 July 2009 for a duration of 6 min 39 seconds, covering some of the most densely inhabited areas on Earth, crossing more than an estimated two billion people, which could end up being the most-watched eclipse in recent history.

Total solar eclipses occur when the moon comes between the Earth and the sun, completely obscuring the sun and this eclipse will be the longest total solar eclipse that will occur in the twenty-first century, which will not be surpassed in duration until 13 June 2132.

The total solar eclipse begins at 6.26 am near Surat in Gujarat on 22 July, from there the Moon's shadow will black out  Varanasi and move towards Arunachal Pradesh.

It will then squeeze between the northern and southern tips of Bangladesh and Nepal before engulfing most of Bhutan. China will be the next view point for much of the morning before leaving the mainland near Shanghai to move over the Ryukyu Islands, Marshall Islands and Kiribati in the Pacific Ocean.

The trajectory of the eclipse covers a span of 2,500km, of which, 900km of the path traverses India. Those in Gujarat, Madhya Pradesh, Uttar Pradesh, Bihar and the northeastern states will be able to watch the entire eclipse while those in other parts of the country can witness a partial eclipse.

Bhavnagar, Surat, Ujjain, Indore, Bhopal, Sagar, Jabalpur, Varanasi, Allahabad, Gaya, Patna, Bhagalpur, Jalpaigudi, Guwahati and Dibrugarh are the Indian cities through which the shadow of total eclipse passes.