The Perseids: On some particular nights you will notice an enhanced meteor activity – a meteor shower. The Perseid meteor showers visit us every July-August and there comes a whole swarm of them. The Perseids have been known since about two millennia. The meteor shower was referred to as the fiery tears of St. Lawrence in ancient lores because a meteoric swarm was noticed to occur between the 9th and 14th August. This is about the time of St Lawrence’s feast day, kept on 10th August – the day he was burned at the stake. That swarm of the shooting stars must be the Perseids!

The Arab legends refer to the shooting stars as firebrands that the angels hurl at the Jinns ever eager to peep into the Heaven. Till the mid-nineteenth century many believed the meteors to be meteorological phenomena

That these are an annual feature was first scientifically established in 1836 by L.A.J. Quetelet. It was G.V. Schiaparelli who first showed in 1866 the connection of a meteor shower with a comet. He gave the August shower the name Perseids, called till then the August meteors.  He found that the Perseids and the Leonid meteor shower streams coincide with the paths of the comets 1862 III (109P/1862 O1; Swift-Tuttle) and the comet 1866 I (55P/1865 Y1; Tempel-Tuttle) respectively. This indicated that comets were losing solid particles as they moved. Meteor streams follow similar orbits round the Sun. The name Perseids is given after the point of origin of the meteor shower, the radiant that lies in the direction of the constellation of Perseus.

https://science.nasa.gov/science-pink/s3fs-public/mnt/medialibrary/2010/08/05/perseidmap_strip.jpg
Perseids map (adopted from: Science@NASA; https://science.nasa.gov/science-news/science-at-nasa/2010/05aug_perseids)

The Perseids are seen during Jul 17-Aug 24 and the showers peak during the night of Aug 11-13. The Perseid meteor shower rate peaks in predawn hours when the sides of the Earth about to turn into the Sun sweep more of them. The right time to look for them is during the hours 22:30-04:30. Your chances are bright if the nights belong to the phase near the New Moon. Besides, you need to be far away from the city lights!

The Zenithal Hour Rate (ZHR) of the Perseids is about a meteor a minute (60-100 per hour), with some fluctuation. It was for instance 20-75 between the years 1953 and 1981 that reached 350 /hr in 1991. A high peak of over 120/hr occurred in 2003-04. In 2010 it was about 30-40/hr. The mean peak magnitude can be -2.7 as bright or even brighter than Jupiter.

Charles P Olivier, the famous astronomer in love with meteor astronomy had this to say of the Perseids in his 1925 book ‘Meteors’:

‘…. of all the annual showers they are the most certain to return with average richness’.

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