Last night I watched the Sickle of Leo the Lion appear in the eastern sky around midnight, a reminder that tomorrow morning (Nov. 17) marks the peak of the annual Leonid meteor shower. Like the summertime Perseids, the Leonids predictably shower us with minor riches every November. I say minor because expectations are 10-15 meteors per hour at maximum from a dark sky site.
That’s not always the case. In 2000 and 2001, the shower put on fabulous shows with hundreds of meteors per hour highlighted by many flaring fireballs. When asked to recall an astronomically significant experience in their lifetime, it’s been my experience that more people pick that shower over anything else, including Halley’s Comet or a lunar eclipse. We’re built to respond to boom, flash and bang.
The Leonids will appear to emanate from the curved Sickle or “Backwards Question Mark” that outlines the head of the lion. You’ll always know you’re seeing a Leonid if you can trace the meteor’s path back into Leo. The best time for watching is well after midnight from about 2 a.m. until dawn Saturday morning; the best directions to face are east or south. No moon will mar the view this year.
Lay out a soft blanket on the ground and cover yourself up with a sleeping bag to stay warm. For a more luxurious experience, consider a padded reclining lawn chair or hot tub. Meteor watching is easy and fun as long as you’re toasty.
Nearly all meteor showers originate with comets and the Leonids are no exception. Its parent comet, named Temple-Tuttle, was discovered in 1865. As it approaches the sun, solar heat boils away ice and entrained dust and small rocks to form the comet’s tail. Ranging in size from sand grains to chocolate chips, the comet’s debris and forms a trail of debris in the comet’s orbital path that gradually spreads out over time.
Every year in mid-November, Earth’s path around the sun takes it straight through Temple-Tuttle’s ancient dust. When the particles strike the atmosphere some 50-80 miles high at over 160,000 mph, friction with the air turns them into those fiery streaks we call meteors.
The Leonids are generally white (colorless) and offer up a mix of the faint and the spectacular. The bright ones often leave glowing smoke trains of ionized air.
Numbers for the shower spike approximately every 33 years when the dusty comet and Earth are in the same vicinity. That last happened around 2000. This year is special however because we’ll have two peaks – tomorrow morning and Tuesday morning the 20th. The second peak originates from a thicker filament of debris shed back in 1400.
Now you have two reasons to set you alarm. Just make sure you don’t accidentally hit the snooze button!