Enki Catena (''Enki'' from the Assyro-Babylonian principal water god of the

Apsu Abzû or Apsû ( Sumerian: ; Akkadian: ), also called (Cuneiform:, ; Sumerian: ; Akkadian: – recorded in Greek as ), is the name for fresh water from underground aquifers which was given a religious fertilising quality in ancie ...

, and ''catena'' from Latin meaning "chain") is a

crater chain A crater chain is a line of Impact crater, craters along the surface of an astronomical body. The descriptor term for crater chains is catena , plural catenae (Latin for "chain"), as specified by the International Astronomical Union's rules on ...

on Ganymede measuring long. This chain of 13 craters was probably formed by a

comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

which was pulled into pieces by

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined a ...

's gravity as it passed too close to the planet. Soon after this breakup, the 13 fragments crashed onto Ganymede in rapid succession. The Enki craters formed across the sharp boundary between areas of bright terrain and dark terrain, delimited by a thin trough running diagonally across the center of this image. The ejecta deposit surrounding the craters appears very bright on the bright terrain. Even though all the craters formed nearly simultaneously, it is difficult to discern any

ejecta Ejecta (; ) are particles ejected from an area. In volcanology, in particular, the term refers to particles including pyroclastic rock, pyroclastic materials (tephra) that came out of a explosive eruption, volcanic explosion and magma eruption v ...

deposit on the dark terrain. This may be because the impacts excavated and mixed dark material into the ejecta and the resulting mix is not apparent against the dark background.

References

See also