The Leonid Meteor Shower
Article for November 2024
Wrap up warm and hope for some clear nights – the Leonids are back!
While November in the UK is known for its glittering displays of fireworks, the Leonids may be quieter, but no less beautiful. Named for the constellation of Leo, from which they appear to originate, this meteor shower lasts from the 3rd November all the way through to 2nd December, and can reach heights of 15 meteors an hour at its peak.
Leo, Latin for lion, is one of the 12 Zodiac constellations and is made up of 9 main bright stars. The brightest, Regulus, at the base of the lion’s chest is actually a quadruple star system! Two binary star pairs that are close enough to appear as a single star to our eyes. Regulus, along with five other stars that form the hook shape of the lion’s head, are also their own asterism, known as the sickle.
The constellation of Leo - Taken from Stellarium
Viewing Leo in November will require staying up late. The meteor shower won’t be visible until around 22:14 each night, with the constellation itself not fully visible until 1am. It will appear on the eastern horizon, below Mars and to the left of Orion. The waning gibbous moon above will also hinder viewing conditions. The peak of the meteor shower is from the night of the 17th November until dawn on the 18th. With the full moon falling on the 15th, it will still be bright in the sky.
The debris that forms the meteors themselves comes from the comet 55P/Tempel-Tuttle, a small comet only 2.24 miles (3.6 kilometres) across, and named for Ernst Tempel and Horace Tuttl – the astronomers who discovered it. The comet has an elliptical orbit that takes 12,100 days (33.13 years) to complete and passes close to the Earth’s orbit. Every November, our planet passes through the trail of debris left behind by the comet that passed years before. Comet dust collides with our atmosphere, burning up as it streaks across the sky.
Every 33 years, 55P/Tempel-Tuttle returns to replenish the debris of its orbit. Because of this, there is a 33 year cycle of the Leonids becoming a ‘meteor storm’ - a display of thousands of shooting stars per hour. The last occurred in 2002, with around 3,000 meteors per hour, but in 1833, the storm is estimated to have produced up to 100,000! Compared to that, we may have to make do with some fireworks!
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