Sunday, May 6, 2012

TRANSIT OF VENUS: A ONCE IN A LIFETIME EVENT (JUNE 5-6,2012)

Unless you plan to live for another 100 years, be sure to watch the daytime sky at the beginning of June. Our neighbouring planet Venus will appear as a black dot because it will pan across the face of our sun.

On June 5 and 6, be prepared to look outside during the day. The once-in-a-lifetime event will last for about six hours on both days and will not occur again until the year 2117.











The entire transit (all four contacts) is visible from:
Northwestern North America
Hawaii
Western Pacific
Northern Asia
Japan
Korea
Eastern China
Philippines
Eastern Australia
New Zealand

The Sun sets while the transit is still in progress from:
Most of North America
The Caribbean
Northwest South America

The transit is already in progress at sunrise for observers in:
Central Asia
Middle East
Europe
Eastern Africa

No portion of the transit will be visible from:
Portugal
Southern Spain
Western Africa
Southeastern 2/3 of South America

The safest way to observe a transit is to project the image of the Sun through a telescope, binoculars, or pinhole onto a screen, but the event can be viewed with the naked eye using filters specifically designed for this purpose, such as an astronomical solar filter with a vacuum-deposited layer of chromium, eclipse viewing glasses, or Grade 14 welder's glass. An earlier method of using exposed black-and-white film as a filter is no longer regarded as safe, as small imperfections or gaps in the film may permit damaging UV rays to pass through. Also, processed color film (unlike black-and-white film) does not contain silver, and is transparent to infra-red. This may result in burns to the retina. Observing the Sun directly without filters can cause a temporary or permanent loss of visual function, as it can damage or destroy retinal cells.

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