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The power of the Leonids

Unlike many meteoroids that Earth encounters, the stuff of the Leonids is orbiting the Sun in the opposite direction as Earth. So it strikes Earth's upper atmosphere at a higher relative speed, more than 160,000 mph (72 kilometers per second). A typical bullet from a rifle, moving at what seems like blinding speed, creeps along by comparison at just 2,240 mph (1,000 meters per second).

The faintest meteor that becomes visible to the average viewer on Earth is typically about 0.6 millimeters across, less than one-tenth of an inch or about the size of a sand grain. The energy it produces could light a 100-watt light bulb for about 2.5 seconds.

Bright fireballs, for which the Leonids are known, can be generated by something the size of a marble, about 9 millimeters in diameter. The power it creates exceeds 1 million joules, or about the same punch as a small car moving at 60 mph. [Learn more about this power]

[Leonids Full Coverage]

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