Most impact marks are from direct hits that produce round craters. This unusually long crater was most likely made by impact from “a train of projectiles striking the planet at a shallow angle.” It’s possible that the projectiles in this train were once part of an intact body.
We know far more about Mars now than we did 60-plus years ago. For a glimpse at the past, check out our “Exploring Mars” feature from the March 1950 issue of Boys’ Life. Click here to read it all.