Sky enthusiasts in the country can witness a three-hour long partial lunar eclipse early Wednesday when the Earth will move between the Sun and the Moon. The eclipse will begin around 1.31 am on Wednesday, the researchand academic director of MP Birla Planetarium in the city, Debiprosad Duarisaid

The greatest partial eclipse when the Moon will look the darkest will be around 3 am. “Sky watchers should not miss this chance since there will be no proper lunar eclipse till 2021,” he said. The celestialphenomenon will be visible entirely from all parts of the country, besides parts of South America, Europe, Africa, Asia and Australia, Duari said.

He said that the Moon will remain partially eclipsed till4:29 am on Wednesday and hence it is a golden opportunity for the skyenthusiasts in the country as the eclipse will be visible almost throughout thenight. “On Tuesday night, only a part of the Moon will pass the Earth’s shadow.Around 3:01 am on Wednesday, 65 per cent of the Moon’s diameter will be underthe shadow of the Earth,” Duari said.

Elaborating on the celestial phenomenon, he said it takes place only at full Moon night, when it, the Sun and the Earth are in a perfectly straight line.

As the Sun’s rays fall on the Earth, its shadow falls on toa patch of space. When the Moon enters the patch of shadow there is a lunare clipse. The patch of the shadow is actually composed of two cone-shaped parts –one nestled inside the other.

The outer shadow or penumbra is a zone where the Earth shadow is partial and blocks some, but not all of the Sun’s rays. In contrast,the inner shadow or umbra is a region where the Earth blocks all direct sunlightfrom reaching the Moon.

When only a part of the Moon passes through the umbra, a partial lunar eclipse is seen. If the entire Moon passes through the umbralshadow, then a total eclipse of the Moon occurs, he said.

India will witness the next lunar eclipse on May 26, 2021,when it will be a total one, he added. When asked, he said lunar eclipses arecompletely safe to view with the naked eye. One does not need a telescope towatch the lunar eclipse although a good pair of binoculars will enhance the experience, Duari said.