Meteorites Possible From Midwest US Fireball

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Meteorites Possible From Midwest US Fireball

By Chow, SPACE.com Staff Writer

Space.com | SPACE.com – 17 hrs

Ohio residents should be on the lookout for potential small meteorites that may

have been created by a bright fireball that streaked over southern Ontario,

Canada, last week, NASA says.

The fireball was detected by all-sky cameras from the Southern Ontario Meteor

Network at 1:22 a.m. EDT (0522 GMT) on Aug. 8.

" It was picked up over Lake Erie and proceeded south-southeast over Ohio, " said

Bill Cooke, head of NASA's Meteoroid Environments Office at the Marshall Space

Flight Center in Huntsville, Ala.

The meteor was last tracked north of Gustavus, Ohio, and the potential impact

zone for meteorite fragments is a region east of Cleveland, Cooke told

SPACE.com.

When would-be meteors are traveling through space, they are known as meteoroids

to astronomers. When they enter Earth's atmosphere to create fireballs, they are

called meteors. Only fragments that actually reach Earth's surface are called

meteorites.

" We look for ones that are moving low and slow, ones that penetrate deep into

the atmosphere, " Cooke said. " Normally meteors burn up 40 to 50 miles (about 65

to 80 kilometers) over your head. This one got down to 38 km (24 miles) before

we lost track of it, and we know it went lower. "

When a meteor penetrates low into the atmosphere and moves relatively slow, it

can create meteorites that fall to the ground, Cooke explained. The fireball

seen last week slowed to approximately 25,200 mph (40,555 kph).

And while skywatchers around the world enjoyed spectacular views of the annual

Perseid meteor shower last week, Cooke clarified that this fireball is

definitely not a Perseid because it is moving too slowly.

Based on the fireball's brightness and radar observations, the meteor's mass is

estimated to be in the range of 22 pounds (10 kilograms). This means that

meteorite fragments will likely be pretty small, Cooke said.

" Something the size of your thumbnail, maybe a bit bigger, " he said, estimating

that any rocks found would probably be about three ounces (roughly 100 grams)

and measure about one to two inches (2.5 to 5 cm) across.

For meteorite hunters in the area, or for anyone who fortuitously stumbles

across any pieces of space rock, Cooke wants to know about it, and people are

encouraged to contact NASA's Meteoroid Environments Office if they find any

fragments.

But, the meteorite expert cautions that there are strict rules governing the

ownership of space rocks that fall from the sky.

" One thing you need to know is that meteorites belong to the property holder,

the owner of the property on which they land, " he said. " So, if you're looking

for them on someone's property, be sure you talk to them and get their

permission first. If you're looking for meteorites, respect the wishes and

rights of all property owners. "