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If you've never experienced a Leonid meteor shower at the 9,157-foot summit of Mount Lemmon, here's your chance.

By Lori Stiles, University Communications
October 26, 2009

Sky gazers can sign up to see what may be one of the best Leonid meteor showers in recent years under dark sky in a southern Arizona alpine setting, courtesy of the University of Arizona Mount Lemmon SkyCenter.

Weather permitting, the SkyCenter's Adam Block will host a special afternoon and evening program at the 9,157-foot summit of Mount Lemmon when the shower is at its peak on Tuesday, Nov. 17.

Visitors can sign up for the 3 p.m. to 2 a.m. program on the SkyCenter Web site or by calling the SkyCenter office at Steward Observatory, 520-626-8122.

Registration costs $70 for adults and $35 for youth ages 7 through 18. Fees cover the cost of a "SkyNights" program, observing through the eyepiece of the SkyCenter's state-of-the-art, 24-inch reflecting telescope until the early morning hours, a sandwich dinner and late-night snacks, souvenirs and prizes.  

Visitors are welcome to bring blankets, chairs and binoculars and experience what it's like to be caught in a meteor shower, when "shooting stars" rain down from a particular direction in the sky – in this case, constellation Leo – at the rate of one or more a minute.

"It's not unlike the perspective of driving in your car through raindrops," Block, an astronomer and renowned astrophotographer, said.

"Of course, a ‘shooting star,' or meteor, is not a star at all, but actually a small chunk of space dust that vaporizes as it hurtles through our atmosphere," he added.

Leonid Meteor Shower

The tiny bits of material that create the Leonid shower were blown off centuries ago by comet Temple-Tuttle. The comet swings by the sun every 33 years on its orbit that extends far into the outer solar system. Temple-Tuttle leaves a trail of debris across Earth's orbit on each passage, a trail at a slightly different location from previous trails.

The trails spread out over time, and each year when Earth plows through different streams, and different parts of streams, comet particles strike Earth's upper atmosphere at more than 160,000 mph – about 70 times faster than a bullet fired from a rifle.  

A debris particle at this speed is moving so fast that it compresses the air in its path, and this searing-hot air, in turn, heats the particle to 3,000 or more degrees Fahrenheit.  At that temperature, debris particles become meteors, the light phenomena seen streaking through the sky.

The comet Temple-Tuttle debris that Earth will pass through in a few weeks is a stream laid down in the year 1466. Scientists have recent evidence that it is denser than earlier predicted.

The Leonids are famous because they have created not just showers, but great meteor storms in the past. The most famous is the Leonid meteor storm of 1833. It illuminated the sky over eastern North America with an estimated 100,000 to 200,000 meteors per hour.

The Mount Lemmon SkyCenter is a unique science center run by the UA Steward Observatory for the College of Science. Its popular programs include SkyNights, Discovery Days, Astronomer Nights and special workshops. Gift certificates are available for all programs and workshops.

The SkyCenter also arranges public tours of the world-famous Steward Observatory Mirror Laboratory. Visitors get a behind-the-scenes look at cutting-edge optical technology and the revolutionary spin-casting processes that are involved in making giant telescope mirrors, from construction of the mold, to spin casting, grinding and polishing.