November 12, 1799 – First Meteor Shower on Record

The Leonids meteor shower occurs each year in November. Every 33 years the Tempel-Tuttle comet adds to the show as thousands of meteors are produced per hour. Andrew Ellicott Douglass witnessed the Leonids meteor shower off the Florida Keys on November 12, 1799. He recorded the event in his journal and it's the earliest known record of a meteor shower in North America.

Leonids Low-Down

The Leonids meteor shower is named after its location in the constellation Leo. The famed 1833 shower was estimated to have over 200,000 meteors per hour! It is credited for the first organized study of meteor astronomy. Another spectacular show in 1966 produced many thousands of meteors per hour.

Above-average Leonid meteor storms usually occur every 33 to 34 years. Donald K. Yeomans of the Jet Propulsion Laboratory determined that the shower's ejected dust was located behind and outside the path of the Temple-Tuttle comet. Yeomans suggested that the showers would be more significant within 2,500 days of the comet's passing.

This meteoroid stream is fast-moving; impact on Earth occurs at 72 km/s. Each show may spread 12 - 13 tons of particles over the Earth. Most of the particles are smaller than the head of a pin.

Leonid Watch 2011

You can watch this year's Leonid meteor shower from late November 17 to early November 18. The moon will be present and it may make viewing difficult. The Leonids are currently in a decline - having last peaked in 2001.

Resources:

http://www.history.com/this-day-in-history/first-meteor-shower-on-record

http://en.wikipedia.org/wiki/Leonids

http://stardate.org/nightsky/meteors

http://earthsky.org/astronomy-essentials/earthskys-meteor-shower-guide

http://meteorshowersonline.com/leonids.html

http://www.aero.org/capabilities/cords/leonids.html

http://www.aero.org/capabilities/cords/images/Glackin-Leonids2001.JPG [image]