Is there less of the moon to love than there used to be?
Yesterday came the news that our natural satellite might have shrunk 100 meters in diameter in relatively recent geologic time. The Lunar Reconnaissance Orbiter found a plethora of scarps across the lunar surface, far more than we knew about before. These cliff-like features can appear on Earth from tectonic shifts, but there’s no continental drift on the moon. Thus, the most likely explanation is: The moon shrunk. If it did, the surface would buckle under the pressure and create these scarps. Astronomers say that the gradual cooling of the moon’s interior probably caused the shrinkage.
Don’t worry about the tides disappearing, though. “Recent” means a different thing to geologists than to everyone else, and in this case it has taken a billion years for the moon to shrink in diameter just 0.003 percent.
For plenty more on the find, check out Phil Plait’s post at Bad Astronomy.
Bad Astronomy: The Moon Is Shrinking!
80beats: Study: There’s Water on the Lunar Surface, but Inside It’s Bone Dry
80beats: Found on the Moon: A Soviet Laser Reflector That Was Lost for 40 Years
Four decades ago, the Soviet Union put a reflector on the moon able to bounce laser signals back to the Earth. There was just one problem: They lost it.
But now the marooned reflector has been found, thanks to the determined hunting of University of California, San Diego researchers. NASA’s Lunar Reconnaissance Orbiter, in orbit around the moon, photographed the landing area where the USSR’s Luna 17 mission dropped off the missing reflector, Lunokhod 1, in 1970. The photos turned up a faint reflective dot, and the team thought that was it.