- LONDON (Reuters) - Europe,
the Middle East and much of Asia and Africa will offer prime viewing next
month for an astronomical event that has not occurred for 122 years --
the transit of the planet Venus across the sun.
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- Weather permitting, for six hours on June 8 astronomers
and the public will be able to see the planet named after the Roman goddess
of love and beauty passing directly between Earth and the sun.
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- The event has been billed as a once in a lifetime experience
because the last transit was on December 6, 1882 and the next one will
not occur until June 6, 2012, but will not be visible in Britain and other
parts of Europe.
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- "Something wonderful, something marvelous is happening
on June 8th and will be witnessed and experienced by millions of people
all over the world," Gordon Bromage, a professor of astronomy at England's
University of Central Lancashire, told a news conference on Tuesday.
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- "It is an extremely rare astrological event."
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- The transit, when Venus will appear as an intense black
dot about 1/30th the diameter of the sun, will be visible in the morning
in Britain, most of Europe and Africa, later in the day in the Middle East
and across Russia and India and later still in the Far East, which will
get a limited view.
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- Scientists warn people not to look at the sun with the
naked eye or through a telescope or camera because it can cause blindness.
A solar filter or eclipse viewer should be used and for just very short
periods.
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- UNUSUAL EVENT OF SCIENTIFIC IMPORTANCE
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- During the transit, the orbits of Venus and the earth,
which tilt at different angles, around the sun will line up exactly. It
occurs four times in every 243 years. There are two December transits,
eight years apart, and then 121.5 years later there are two June transits,
also eight years apart. After another 105.5 years the cycle begins again.
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- "It is a very special period of six hours,"
said Bromage.
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- British astronomer Jeremiah Horrocks recorded the first
transit of Venus across the sun in 1639.
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- The event is significant because it happens so rarely.
Previous transits have also given scientists an opportunity to measure
the scale of the universe and the distance from the Earth to the sun, which
is called the astronomical unit (AU).
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- "Without that we couldn't measure any distances
in the universe. Every other distances we measure...are all derived from
the measurement of this basic yardstick -- the distance from the Earth
to the sun," Bromage said.
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- Astronomers are also interested in the general principle
of planet transits to hunt for extrasolar planetary systems.
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- It will allow scientists to study the famous "black
drop" problem which makes timing the transits difficult. As the black
disc of Venus appears on the sun it seems to have a dark neck, or become
pear-shaped, for a short time. The opposite occurs when it leaves the sun.
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