The most anticipated meteor shower of the year, the Perseids, will peak on the night on August 12/13 when around 80 meteors per hour might be seen. At the present time only the Geminids in December and the Quadrantids in January produce more meteors. Some meteors will be seen a few days before this date and a day or so after.
Many people know meteors as 'shooting stars', but they have
nothing at all to do with stars. They are tiny grains of dust that burn up when
they enter Earth’s atmosphere. They travel at speeds ranging from 20 to 50
miles per second and we see the result of their destruction in the form of a
brief streak of light across the sky.
Although a few sporadic meteors can be seen on any night of
the year, there are periods when many can be seen, and these are referred to as
meteor showers. These meteors are connected with comets. Comets are essentially
very large, dirty snowballs travelling around the Sun. Comets leave a trail of
dust behind them and if Earth happens to pass through one of these dust trails
we see a meteor shower. There are
several major meteor showers during the course of the year.
The Perseids are connected with comet Swift-Tuttle, which
was discovered by the American astronomers Lewis Swift and Horrace Tuttle in
1862. This comet takes 133 years to obit the Sun. The Perseid meteor shower has
a very long history. The meteors are
called Perseids because if you track their paths across the sky they all appear
to come from the constellation of Perseus.
It should be possible to see the Perseids after about 11pm, at first
from the north east, but as the night goes on, all over the sky.
An old name for the Perseid meteors shower is 'the Tears of
St. Lawrence'. In 258 in Rome a Christian named Laurentius, sometimes referred
to as Lawrence, offered the Roman Emperor Valerian 'all the wealth of the
empire'. Valerian believed that he meant gold and treasure, but Laurentius
meant the people of the empire. Valerian was very annoyed when he did not get
the treasure he was expecting and had Laurentius murdered barbarically, by
being roasted alive.
The execution was on August 9, and when, the following
evening, the Perseids came through on schedule, people thought these meteors
were tears from heaven, hence the name ‘the Tears of St. Lawrence’.
The story then goes forward to August 1535 when the French
explorer Jacques Cartier was exploring the part of the ‘new world’ that today
we call Canada. While camped beside a large river he saw the Perseid meteor
shower. Knowing the story of St. Lawrence and being the first European there,
he named it the St. Lawrence River. Thus this great river in Canada owes its
name to a French explorer and a meteor shower.
www.theramblingastronomer.co.uk
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