By Emma Wride
What are the Perseids?
The Perseids meteor shower is a spectacular display of shooting stars that occurs annually with the peak of the shower during mid-August. They are known as the Perseids because the radiant (the point at which they appear to come from in the sky) is in the constellation of Perseus.
The effect is caused by Earth passing through a cloud of debris left behind by comet Swift-Tuttle when it passed through Earth’s orbit in 1992. As the comet approaches the Sun, the heat from the sun causes the ice in the comet to turn into water vapour and other gases, which also releases dust particles. This cloud of dust sits in space and Earth passes through it every year on its orbit around the Sun. Tiny particles of dust no bigger than a grain of sand interacts with Earth’s atmosphere. Friction from the particles moving through Earth’s atmosphere causes these particles to burn up and as they disintegrate streaks of light can be seen across the night sky. At its peak the rate of meteors can be around 60 per hour.
Photo taken by Pete Williamson of the Perseids 2014
Comet Swift-Tuttle was first ...