Every November the region of the night sky associated with the constellation of Leo is filled with a prolific meteor shower, known as the Leonids. The Leonids generally occur each year between November 13th and November 21st, reaching its peak on around the 17th, when 20 to 30 meteors can be seen each hour. However, every 33 years a periodic meteor storm occurs when thousands of meteors can be observed every hour, the next of which is due to occur in 2032.
Although the meteors appear to radiate from the Leo constellation, it is in fact caused by the Earth intersecting a trail of dust left behind by the Tempel-Tuttle comet during its countless journeys orbiting the Sun. As the comet’s trailing debris particles, known as ‘meteoroids’, hit then vaporize in Earth’s atmosphere at around 158,000 mph (256,000km/h), they produce the streaks of light in the sky we call meteors or shooting stars. Most meteoroids are completely incinerated around 60miles above the ground, but those few making it all the way to the Earth’ surface are known as meteorites.
The Leonids have apparently been observed since 902 A.D, which Arab historical accounts refer to as the “Year of the Stars,” and Chinese astronomers as the year “stars fell as rain.” However, the spectacular Leonid meteor storm of 1833 is credited with launching the modern study of meteors, and caused such widespread panic in the United States that many people feared that it was the end of the world.
Then, as many as two hundred thousand meteors an hour were seen in the November night sky and such was the Leonids’ intensity that many people were woken from their sleep by what appeared to be the sky on fire or by the commotion coming from the streets. However, all survived the night intact but they might have been able to better enjoy the spectacle had they known it was more likely they would be struck seven times in a row by lightning than being hit by a falling meteorite.
More fun facts about the Leonid Meteor Shower can be found here.