Exodus Indigo was an ECHO Colony Ship deployed during the Collapse. It carried several high-ranking Ishtar Collective scientists, including Maya Sundaresh and Chioma Esi. It landed on Neptune after detecting a Vex distress signal, likely originating from a submind of the Vex-derived AI Soteria that had landed there earlier.
En route to Neptune, the ship was attacked by an unknown entity which left a spear-like weapon embedded in the hull.