A SPECTACULAR sight should be seen over the Armagh skies tonight (Monday), with the culmination of a Perseid meteor shower.
Up to 100 meteors an hour may be seen late in the evening – depending, of course, on the cloud cover.
Armagh Observatory has said that, despite the prolific activity, an individual may only see a fraction of this number depending on how clear the skies are.
“Most people observing from a dark, clear observing site should expect to see around a dozen meteors per hour,” a spokesperson said.
The Perseid meteors take their name from that of the constellation, Perseus, from where they appear to radiate.
They are usually one of the most reliable annual meteor displays. The meteors are generally fast and bright and may leave glowing ‘persistent trains’.
Most meteors are produced by comets, which shed trails of dust while passing through the inner solar system on their elliptical orbits around the Sun, but in this case, the comet is a ‘Halley-type’ short-period comet.
In the case of the Perseids, the Earth encounters this dust at high speed – over 200,000 kilometres per hour – and this causes the small dust grains, with sizes ranging from typically a few millimetres up to a centimetre or more, to vaporize in the Earth’s atmosphere at a height of almost 100 kilometres.
It is this vaporisation, or burning up of the dust in the Earth’s atmosphere, that produces the visible meteor.
During the late evening tonight, the constellation Perseus will lie low in the north.
In order to see the Perseids to best effect, the Armagh Observatory recommends to find a dark, clear site with a good vista towards the north or east.
You should always avoid light pollution and allow time for your eyes to become accustomed to the dark.
Then, look at an angle of about 45 degrees away from the radiant, in this case the rising constellation of Perseus, keeping the radiant near the edge of your field of view.