Kochi: It is a once-in-a-lifetime opportunity and scientists from across the globe are thronging southern India to watch the 'Ring of Fire' during the millennium's longest annular solar eclipse on Friday. The southern tips of Kerala and Tamil Nadu will offer the best view of the moon obscuring the sun.

In India, the eclipse will start around 11 a.m. from Kerala and end around 3.15 p.m. at Mizoram. The 'Ring of Fire' will be best seen in the Kanyakumari in Tamil Nadu and then in Rameshwaram and Dhanushkodi, where it will be visible for the longest 10 minutes and 13 seconds.

"I came to know that India is one of the best destination to watch the annular solar eclipse. I am going to Kanyakumari as it lies in the central line of the eclipse route and the 'Ring of Fire' will be visible quite clearly," American astronomer Jay Pasachoff told the sources.

Pasachoff, a Professor of Astronomy at Williams College in Massachusetts (US), has travelled to India twice before in 1980 and 1995 to watch the solar eclipse. This will be the 50th solar eclipse he chases around the globe.

An annular solar eclipse occurs when the sun and the moon are exactly in line, but the apparent size of the moon's shadow is smaller than the visible disc of the sun. The covered sun, therefore, appears as a 'Ring of Fire', with its rays appearing spread out from the outline of the moon.

The last time India saw this Ring of Fire was Nov 22, 1965, and it will not be witnessed again before June 21, 2020. The maximum duration of this year's eclipse will be 11 minutes, 8 seconds over the Indian Ocean, thus making it the longest annular eclipse of the millennium. The next longer annular eclipse will be observed in 3043.

Kerala, although not in central line of solar eclipse, has become a hot destination for scientists and astronomers who wants to watch Bailey's beads during the eclipse.

As the moon covers the sun during a solar eclipse, the undulations on the moon's surface allow sunlight to shine through in some places, looking like beads. This effect is called Bailey's beads in honor of Francis Bailey who first provided an exact explanation of the phenomenon in 1836.

"I will be travelling between Varkala and Thiruvananthapuram in Kerala to capture the image of Bailey's beads. It's an interesting phenomenon to see and one has to be at the edge of the eclipse route to catch it. We will be taking some scientific readings and measurements for research," N. Rathnasree, director of New Delhi's Nehru Planetarium, told the sources.

Rathnasree also plans to do photograph some heritage buildings during the eclipse.

"I along with my team will click shots of some important monuments in Kerala with annular eclipse in the backdrop," she said.

Science Popularisation Association of Communicators and Educators (SPACE), a Delhi-based organisation working to make science and astronomy popular among youngsters, is taking people to Varkala in Kerala to watch the eclipse.

"We have a team of 70 people both from scientific and non-scientific community including some children. We will be doing several experiments like recording temperature, humidity, wind speed and ambient light during the eclipse. We are carrying several telescopes, solar filters and high resolution camera to catch the eclipse," said Sachin Bhamba, astronomer with SPACE.

SPACE has also initiated a study about impact of solar eclipse on people.

"There are all kind of superstitions around a solar eclipse -- like you should not eat or drink during an eclipse. We are taking 35 people to Varkala and will make them do every routine thing during the eclipse. They will be later asked to share the changes they felt during the celestial activity. We will publish a study based on the data so that people cast away all false beliefs related to eclipse," said Bhamba.

With the sky clear, scientists are hoping to catch a once-in-a-lifetime view of the eclipse on Friday. IANS