Acrater chain is a line ofcraters along the surface of an astronomical body. The descriptor term for crater chains iscatena/kəˈtiːnə/, plural catenae/kəˈtiːniː/ (Latin for "chain"), as specified by theInternational Astronomical Union's rules onplanetary nomenclature.[1]
Many examples of such chains are thought to have been formed by the impact of a body that was broken up bytidal forces into a string of smaller objects following roughly the same orbit. An example of such a tidally disrupted body that was observed prior to its impact onJupiter isComet Shoemaker-Levy 9. During theVoyager observations of the Jupiter system, planetary scientists identified 13 crater chains onCallisto and three onGanymede (except those formed bysecondary craters).[2] Later some of these chains turned out to be secondary or tectonic features, but some other chains were discovered. As of 1996, eight primary chains on Callisto and three on Ganymede were confirmed.[3]
However, other crater chains, such as many of those onMars, represent chains ofcollapse pits associated withgrabens (see, for example, the Tithoniae Catenae nearTithonium Chasma). Crater chains may also be formed by a sequence of explosivecryovolcanic eruptions, such asSet Catena onNeptune's moonTriton.[4]
Crater chains seen on theMoon often radiate from larger craters, and in such cases are thought to be either caused bysecondary impacts of the larger crater'sejecta or by volcanic venting activity along a rift.[5]
