Century's second Venus transit on June 6
Kolkata: In a rare celestial occurrence, Venus - the second planet from the Sun and the Earth's neighbour - will transit across the solar disc early June 6.
The transits of Venus occur in pairs (within eight years) with more than a century separating each pair, according to an M.P. Birla Planetarium official here. The last transit of the planet was seen on June 8, 2004.
The celestial event, lasting for about five hours 40 minutes, will start around 3:40 a.m. at locations in and around Kolkata. Hence, the beginning of the celestial happening will not be visible until the sunrise, said Debiprosad Duari, the planetarium's director (research and academic).
The occurrence will be visible from anywhere in India. The greatest transit, when the black dot of venus can be observed at the innermost point of the solar disc, will occur around 7:02 a.m., Duari said. The transit will end (called egress) around 10:20 a.m.
The small disc of Venus will touch the Sun's disc internally at 10:04 a.m., and by 10:21 a.m. will be completely out of it. The transit can be viewed properly only after half an hour post sunrise, Duari added.
The entire event (i.e., the four contacts) of the transit, will be visible from eastern Australia, New Zealand, New Guinea, the Philippines, north Asia, eastern China, Korea, Japan, islands in the western Pacific Ocean, Hawaii, Russia, Alaska and north-west Canada.
Only the first part of the transit will be visible before the sunset from eastern Canada, the US, Central America, the Caribbean and northwest South America. The last part of the transit will be visible in western Asia, India, Europe, the Middle East and eastern Africa.
Throughout the world, tremendous amount of interest has been generated for this event, as the next transit will occur in 2117.
"One needs to be extremely cautious while observing this event, as Venus will only cover 1/32 of the sun's disc, and looking at the Sun with the naked eye should be completely avoided.
"One should look at this event through scientifically-tested aluminised Mylar filter (also called solar goggles) or, No.14 Welder's glass. Under no circumstances one should use exposed x-ray plate or smoked glass to look directly at the transit of Venus," Duari said.
Historically, the discovery of the transit of Venus not only started a new era of scientific experimentation through international collaborations, but also gave us the first concrete concept of the structure of the solar system.