As soon as you enter the Oborum system at the end of the previous mission, you automatically begin this mission, and The Hunter hails you from his ship, Scorpius. You can ask questions if you want, and then tell him you’ll dock (or not) — either way, you’ll need to board the ship to continue the mission. Target the Scorpius, approach and dock, then board the ship.
Talk to the Hunter
Once on the ship, walk forward a bit and a conversation will start. This is perhaps the most important conversation in the game, lore-wise, so if you care about the story, make sure you pay attention — you’ll also want to note who (or perhaps ‘what’) the Emissary and the Hunter actually are.
After the mandatory conversation ends, you’ll be able to question both The Emissary and The Hunter. It’s well worth doing if you want to fully understand what Unity is, and to understand the goals of The Emissary and The Hunter.
Leave the Scorpius/Talk to the Emissary
When you’re ready, turn around and head back to the airlock. The Emissary will stop you before you reach it, and give you a few resources and the key to the Moon Base on Luna. He’ll tell you to head to the moon base, and to talk with your companions in Constellation. When the conversation ends, you’ll have completed this mission.
You can do two different main story missions now: Unearthed, and Final Glimpses — these can be done in any order, but Final Glimpses requires a Grav Jump that you can’t do with the default Frontier and no levels in Astrodynamics, so if you don’t have any spare skill points and/or don’t want to fuss with building a new ship (or stealing one), you may want to do Unearthed first; it will help you level up, allowing you to then spend your new skill point in Astrodynamics.