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Stargazers in the Americas, Europe and Africa are in for an unusual show late Tuesday and early Wednesday, the peak of the annual Leonid meteor shower.

Jarle Aasland captured this 2002 Leonid meteor over Norway. [File photo]

The shower is not expected to be as spectacular as the last few years, but it should still be interesting, said Frans Rietmeijr, a professor in the University of New Mexico's earth and planetary sciences department.

Meteors come from tiny remnants of comets, which leave trails of dust and debris that the Earth slams into periodically.

The centimeter-sized comet pieces can produce hundreds of fireballs or more each hour. In some cases, particularly during the Leonids, the fireballs make bright trails, sometimes called glowworms in the sky, that can stay up for 10 to 15 minutes, according to astronomers.

Each November, Earth flies into the debris trail from Comet Tempel-Tuttle, which produces the Leonids. And every 33 years, our planet enters a particularly thick Tempel-Tuttle cloud, sparking an exceptionally strong meteor shower. Then, the next few years produce nice displays, after which the Leonids tend to putter out for awhile.

Last year marked the last strong Leonid season expected for years to come.

SPACE ROCK PRIMER

SPACE ROCK PRIMER A meteoroid is a pebble or stone in space. A meteor is the bright flash of light that a meteoroid produces as it streaks across the sky, and also refers to the nugget itself while in the atmosphere. A meteorite is a meteoroid that survives atmospheric entry and strikes Earth.

A meteoroid is a pebble or stone in space. A meteor is the bright flash of light that a meteoroid produces as it streaks across the sky, and also refers to the nugget itself while in the atmosphere. A meteorite is a meteoroid that survives atmospheric entry and strikes Earth.

But even if glowworms don't show up, this year's event still offers a good opportunity to see meteors, LodeStar Astronomy Center's manager Laurel Ladwig said.

Clear skies permitting, observers in dark areas away from city lights could see 60 meteors an hour, astronomers predict. Eastern North America could have a prime seat for the show, as well as Alaska and Hawaii, according to NASA scientist Bill Cooke and others.

The best time to look up is generally between 11 p.m. Tuesday night until dawn Wednesday, local time.

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