What is the requirement for researching the Rift Sphere?

[Karamethien]

Is the tech to explore Rift unique to the Rift Origin? On my current run, I am mostly researching repeated tech now and the Rift Tech still has not shown up.

[Bermag]

You need Astral Sphere technology. You get that from a situation.

[CrUsHeR]

You need to encounter an astral scar. This unlocks the tech to mine this resource.

Once you have that, there's gonna be a situation to monitor. By completing that, you unlock the rift sphere tech.