sábado, 1 de novembro de 2014
Mingle with meteorites at Cincinnati Observatory
Frequently, people bring interesting rocks to the Cincinnati Observatory in the hopes that they have discovered a meteorite. Unfortunately, every one of them has been a plain, old Earth rock: a meteor-wrong.
Meteorites fall to Earth daily, but finding a large one is extremely rare. Only about a dozen large meteorite falls have been verified in Ohio, ever.
What to look for
The easiest meteorites to find are magnetic. Although there are naturally magnetic Earth rocks, finding a rock that sticks to a magnet is a good start. Magnetic meteorites formed in the centers of large asteroids that shattered, orbited the Sun for eons and slammed into the Earth.
Meteorites are almost always dark in color. This black fusion crust developed during the brief, fiery moments when the rock plunged through the Earth’s atmosphere. When this happens, we call that streak of light a shooting star.
Large meteorites can have pits in them that look like thumbprints. Called regmaglypts, they formed on the space rocks as they plummeted through the atmosphere as well.
You probably won’t get rich finding meteorites in Ohio (we have some in our gift shop for as little as $5), but on Saturday at the Observatory you’ll have a chance to hold meteorites from around the world. You can even see most of those that fell in Ohio since the beginning of time. ■
Dean Regas is the outreach astronomer at the Cincinnati Observatory and co-host of PBS’ “Star Gazers.” He can be reached at firstname.lastname@example.org.
If you go
What: Meet a Meteorite: Gathering the best meteorite collections in the Tristate for the public to explore, touch and buy – including pieces of the moon and Mars; plus, viewing of the moon through the old telescope (if clear)
When: 7-10 p.m. Saturday
Where: Cincinnati Observatory, 3489 Observatory Place, Mt. Lookout
Admission: $10 adult, $5 student; no reservations needed
Information: www.cincinnatiobserv atory.org
Publicado por Jorge M. Gonçalves às 4:55 da tarde