linear chains of craters tagged posts

In this spacecraft image of Phobos, red arrows indicate a chain of small craters whose origin researchers were able to trace back to a primary impact at the large crater known as Grildrig. Credit: ESA/Mars Express, modified by Nayak & Asphaug; copyrighted image

Some of the mysterious grooves on Mars’ moon Phobos are the result of debris ejected by impacts eventually falling back onto the surface to form linear chains of craters, according to a new study. One set of grooves on Phobos are thought to be stress fractures resulting from the tidal pull of Mars. The new study addresses another set of grooves that do not fit that explanation. “These grooves cut across the tidal fields, so they require another mechanism...