However this year’s edition is not expected to be particularly spectacular, and will lack “any significant activity” according to Space.com. 10-15 meteors are expected to be observed per hour, far less than the 1833 meteor shower, during which around 72,000 meteors entered the atmosphere per hour.
Leonid meteor shower: Comet trail
The meteors are caused by debris left by Comet Tempel-Tuttle, which passes close to Earth every 33 years. Deborah Netburn of the Los Angeles Times says that “when the Earth moves through the comet’s orbital path that dusty debris burns up in our atmosphere, causing what looks like shooting stars to streak across the night sky.”
The Comet last passed through the inner solar system in 1998, leading to amazing Leonid meteor showers in 1999, 2001 and 2002. Since then the number of meteors observed per hour has been in decline. It has been predicted that this year there will be long periods during which not a single meteor will be observed, with activity reaching its peak just before sunrise.
Although the Earth moves through other comet trails at various points throughout the year, Comet Tempel-Tuttle has a good record of leaving behind sizable pieces of matter. The debris enters the Earth’s atmosphere at speeds of over 40 miles per second, so even a pebble can turn into a fireball.
Watching Leonid meteor shower
Leonid got its name because the meteors appear to fall from within the constellation of Leo, or the Lion, which is easy to observe at this time of year. If you want to watch the celestial event, it is advised to move away from well-lit areas and turn to the East, where the constellation will be visible in a clear sky.
If your view of the event is obscured by weather conditions or light pollution, or you live in a colder area of the country, you might prefer to watch one of various webcasts. Both Slooh and NASA will broadcast the event. Slooh will broadcast views from the Canary Islands and Prescott, Arizona, and NASA will include a telescope view from the Marshall Space Flight Center, Alabama.