the vectors

 

In contrast to the Coordinates, Vectors aren't pointing towards any destination. It's all about the journey itself, about the Pilgrimage.

Primary Vectors were calculated by the Sages of Old Earth, the first Prophets, still biological and 'alive' in human understanding of the term. The process lasted for decades and started when the first visions of the Destroyer came.
Almost all Primary Vectors point outward from the Galactic Core.
It is said that no one should join the Pilgrimages of the Primary Sectors. One must be born already following them to participate and not cease to be.

Secondary Vectors are the creation of the Artificial Prophets, after the Synthetic Minds had ascended into godhood*. They were needed to establish the new Pilgrimages, as it seemed that following the Primary ones became impossible.
Even though only few Secondary Vectors point towards the Galactic Halo, not a single one is leading towards the Core.

Zero Vector is considered an error, an unexplained glitch in the Prophetic Cortexes. Only the invention of the dreadful Null Drive brought a meaning to it. Zero Nomads follow it to this day. 
No one knows where the Zero Vector is leading.

The Path of Chaos is not a Vector. It's just a twisted and convoluted set of instructions that is constantly changing. The Riders of Entropy had corrupted all their navigational systems and drove all their Prophets insane. It allowed them to figure out the Path. They are the only ones following it, no one else is that insane to even try to look for it.
Scholars of the Void claim that the Path was always there - that 'it just waited in the patterns of nothingness to be discovered.'

Tertiary Vectors haven't been calculated yet. Some Pilgrims assume that they will lead to the Core. It's widely believed that the entities capable of establishing the Tertiary Vectors do not exist yet or haven't been discovered.

*) (for some) this is the Arch-Heresy of our time, the very end of the H-tip of the triangle. No one should compare something so insignificant like anything human-related to the Overlords of the Abyss. The Destroyer is pan-temporal, thus his coming is to put these blasphemies to an end.