From Destinypedia, the Destiny wiki
The Sol Collective is a Vex programming collective found in the Arcadian Valley on Nessus, Echo Mesa on Io, the Fields of Glass on Mercury, and on Europa. These Vex have bronze frames with a seafoam patina, with some such as Storm Minotaurs and Axis Minds having a more pronounced patina.
According to the Drifter, the Sol Collective are the main overarching collective of Vex in the Solar System after having consolidated their subtypes as a result of the Guardians and their efforts against them on Mars and Venus. Their presence as a united front was previously undocumented as its members were not encountered until the Red War.
Evidence points that it is currently the largest Vex collective present in the system, due to how many Axis Minds are in charge of it. They may be direct descendants of the Precursors, who converted Mercury, due to their heavy presence on that planet.
They are also responsible for the conversion of Nessus into a machine world, and are attempting to do the same for Io. Strangely, it is unknown if they have a presence on Mars or Venus, both of which are hubs of Vex activity and incomplete Machine Worlds, though it is possible the Vex as a whole may have been driven off of Mars due to the efforts of the Red Legion
Leading Axis Minds
List of appearances