Rugged craters upon craters in the southern highlands of the Moon. The biggest one here is Clavius. It's about 230 km across or roughly the size of Massachusetts, Connecticut, and Rhode Island combined.
Clavius is very old. It was formed nearly 4 billion years ago by a gigantic impact and is one of the biggest craters on the Moon that wasn't later flooded by lava to become a "sea." Just last month, NASA announced the discovery of water trapped in tiny glass beads all over the surface of Clavius. I like the way the smaller craters trace out a graceful arc along the floor of the huge crater.
The smaller but very round crater near the bottom of the photo is Tycho, which is about 40x younger than Clavius -- only 108 million years. It's about 50 miles across and more than 15,000 feet deep! There's a big mountain range in the center that was formed by the rebound ("splash!") of lunar crust immediately after the impact.
Sunrise on the Moon is amazing! There's no air so the shadows are absolutely black without a hint of dawn until the moment the sun slips suddenly over the mountains. The lunar day is 29 Earth-days long, so the shadows creep slowly across the plains over a period of many hours.
The Moon keeps just its one face toward the Earth, so from the Moon the Earth never rises or sets -- it just hangs almost motionless in one place in the sky as the Sun and stars wheel slowly past. The enormous blue/white/green/brown Earth marble spins endlessly against the black velvet vacuum surrounded by the eternal stars. It goes through phases (new, half, full, etc) but never moves from its fixed point in the sky.
Clavius was the location of the lunar base from which astronauts in the movie "2001: A Space Odyssey" traveled to see the mysterious monolith which had just been excavated in Tycho. When sunlight first touched the monolith it sent out a loud radio signal to alert aliens near Jupiter and led to the crazy "open the pod-bay doors Hal" journey later in the film.
buhhh ... buhhh ... buhhh. BAH-BUM!
This is a stack of 200 x 0.1 sec exposures (best of 1000) through a C8edgeHD with a focal length of 2040 mm. I'm very much enjoying my new three-volume book "Luna Cognita," as you can easily tell!
A wonderful pandemic hobby.
Edited by airscottdenning, 29 November 2020 - 11:38 AM.