Most years, the November Leonid meteor shower passes without much notice or fanfare. However, this year may be different, as experts predict a rare meteor outburst overnight tonight.

Every November, Earth passes through a stream of debris in space, left behind by a nearly 2-km-wide chunk of dusty ice known as comet 55P/Tempel-Tuttle. The comet crosses Earth’s orbit once every 33 years. With its last flyby in 1998, it is now way out near the orbit of Saturn, slowly making its way back toward the Sun.

Each year, throughout November, tiny bits of comet Tempel-Tuttle are swept up by Earth’s atmosphere and go streaking through the sky as bright meteors. With these meteors all appearing to originate from within the constellation Leo, this is known as the Leonid meteor shower.

The radiant of the Leonid meteor shower, in the eastern sky, at around 1 a.m. EST on Saturday, November 19, 2022. Credit: Stellarium/Scott Sutherland

Although Leonid meteors can be seen all month long, the night of November 17 is usually the best time to look up. That’s when Earth reaches the densest part of the debris stream and thus produces the greatest number of meteors.

This meteor shower typically only produces a handful of fast, bright meteors each hour, even during its peak. Individually, these meteor flashes can be pretty impressive. Due to their speed, at over 70 kilometres per second, Leonid meteors can also produce a phenomenon called “persistent trains”…