It has been uncovered, but because of its large mass has never been moved from where it fell. The main mass is estimated at more than 60 tons,making it the largest known meteorite (as a single piece) and the most massive naturally occurring piece of iron known at the Earth's surface.
The Hoba meteorite is thought to have fallen more recently than 80,000 years ago. It is inferred that the Earth's atmosphere slowed the object to the point that it fell to the surface at terminal velocity, thereby remaining intact and causing little excavation. Assuming a drag coefficient of about 1.3, the meteor would have been slowed to a mere 320m/s (contrast this with typical orbital speeds of several km/s). The meteorite is unusual in that it is flat on both major surfaces, possibly causing it to have skipped across the top of the atmosphere in the way a flat stone skips on water.
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