Impressive block of lucite demonstrating the effects of a hypervelocity impact of a micrometeoroid traveling at speeds of about 20,000 feet per second, or five miles per second. The block measures 8″ x 8″ x 3″ and was impacted at the center by a tiny nylon disc (3/8″ in diameter and 1/32″ thick, a sample of which is taped to the top) resulting in substantial ballistic damage to the block and a circular spall broken off the back from the ultra high-speed impact. Traveling faster than the speed of sound, the disc precedes the shockwave momentarily and the resulting shock wave and energy from the projectile combine to knock out a spall on the far side. The block is etched in the upper right corner: "4-462." In very good to fine condition, with a chip to one corner of the block and the spall fragment reattached to the back with tape.
From the collection of Dr. Otto Berg.
