The Leonids is a meteor shower that occurs every year in mid-November (typically between the 13th and 20th). The meteors are called Leonids because they seem to radiate out of the constellation Leo (making Leo their "radiant").

Most meteors are produced by comets, and the Leonids are no exception. Every year, the Earth passes through the ice- and dust-trail of the comet Tempel-Tuttle (which can be seen every 33 years), resulting in a sometimes spectacular meteor shower.

In some cases, when the Earth travels through fresh cometary matter rates increase drastically, and if we're lucky we will see a meteor storm with up to several thousand meteors per hour, even several per second in short bursts.

The Leonids are fast meteors, causing them to leave bright trails, which can last from a few seconds to several minutes. The particles, usually between 1 mm and 1 cm in diameter, enter our atmosphere in speeds exceeding 158,000 mph.

The best way to observe the show is to dress warm, and lie down with your feet pointing east, towards Leo. Looking directly at the radiant isn't necessarily the best way to observe. Instead, look around and above it.