That's because there wasn't. All we've ever gotten is vague mentions that someone had their eyes on the Station. We were originally sent down to avoid a potential attack, and at one point they wanted us to learn how to use the shuttles, "just in case."

[ Which hadn't been a particularly enjoyable experience for 76 and Rocket, when using the controls had required a sort of emotional synchronization. They'd managed to get back down to the planet in one piece, at least.

76 crosses his arms over his chest and shakes his head to himself. ]

Gotta wonder who would pose any kind of threat to the Natha, given what they're capable of.