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by wishfish 78 days ago
Zoomed into several of the lunar surface photos and noticed some of the very small impact craters are in a regularly spaced straight line.

Looks to me as if a meteorite came in at a shallow angle and basically skipped across the surface. Leaving dimpled craters as it bounced. Looks very similar to rocks skipping on a pond. Am I correct or is there another explanation for these?

2 comments

If I am understanding correctly you are seeing https://en.wikipedia.org/wiki/Crater_chain which are craters caused by debris blasted out when another crater is formed.
Thank you! Glad to see there's a Wikipedia article about it. And good to learn the formal name for this formation: "catena" (plural "catenae").
A chain of meteors would strike the surface in a line as the moon moves
A single “rubble pile” asteroid will easily break apart when nearing a celestial body, once it crosses the Roche limit. It will break apart into a perfectly straight line too (at least the impact craters will.) I would guess most of the straight-line series of craters are all caused by something like this.
Strafing fire from an alien warship will leave similar craters, assuming sufficiently large kinetic energy weapons.