“Genesis Rock”

Almost 40 years ago this day [July 30th, 19171] Apollo 15 landed on the Moon. And one of the items brought back to Earth was the so-called “Genesis Rock” which after analysis was dated to be 4.5 billion years old making it almost as old as the solar system and considerably older than any rock formed on earth. The rock is an anorthosite, composed mostly of the plagioclase feldspar, anorthite.

Bill Ashworth from Linda Hall Library wrote...

"Apollo 15 landed on the Moon on July 30, 1971, not quite forty years ago. This was the fourth Apollo mission to land on the lunar surface, and the first that was targeted for one of the highland areas, in this case, a region in the lunar Apennines called Hadley Rille. Apollo 15 was also the first to carry a land vehicle, the Lunar Rover, which spared the astronauts from having to walk and lug around their lunar rocks. The Lunar Rover was a pretty amazing piece of transportation; it ran on batteries, with an electric motor powering each wheel and the steering. It weighed just over 400 pounds, and could carry nearly 1000 pounds of payload. Imagine trying to put 5000 lbs into a half-ton pickup! The rovers were not returned to Earth, so there are three of them still on the moon, just waiting for you, if you sign up for a tourist package. Just bring along two Delco 36-volt silver-zinc potassium hydroxide batteries--I am sure you can find these at Sears. And speaking of lunar rocks, one of the big finds of Apollo 15 was the “Genesis Rock”, an igneous rock containing mostly plagioclase feldspar, which means it must be very old. White and sparkly (and about the size of a small loaf of bread), the rock was immediately recognized by the geologically-trained astronauts as significant. It rode back on the Lunar Rover to the spacecraft, and thence to the Lunar Lab on earth...."