Hephaestus Fossae (Mars)

This feature is named after an earlier feature.

The fossae have been tentatively identified as outflow channels, but their origin and evolution remain ambiguous. It has been proposed that water may have been released into the troughs as a catastrophic flood due to subsurface ice melting following a large bolide impact. (wikipedia entry)

A fossa is a long, narrow, shallow depression. On Mars they are named after the nearest named albedo feature on the Schiaparelli or Antoniadi maps.