Crater chain
A crater chain is a line of craters, made by a broken-up comet or asteroid or by ejecta from a large impact.
A crater chain is a row of craters lined up along a straight or gently curving path. Planetary scientists use the Latin word catena for such chains on other worlds.
There are two main causes. Some chains are made by a string of fragments from a body that broke up before impact, as Comet Shoemaker–Levy 9 did before it struck Jupiter in 1994. Chains on Jupiter's moons Callisto and Ganymede are thought to have formed this way, from comets torn apart by Jupiter's gravity. Others are made by blocks of ejecta landing in sequence after a large impact, forming lines of secondary craters.
On Earth, some researchers have proposed that a few lines of craters might record a broken-up impactor, but such claims are difficult to prove because the craters must be shown to have the same age. Crater chains illustrate how fragile comets and asteroids can be, and how impacts can produce patterns across whole landscapes.
Related terms
Level: Expert Advanced