It was a tiny area compared to galactic scale. Only about 100 light years across. When the race happened upon a periphery, and detected the new signals, there was great excitement among their scientists. They naturally tried to keep it quiet. But just as on Earth, when a new species is first detected, word tends to spread. Slowly at first, then faster and faster, the news trickled from one advanced race to another. It was within a relatively short span of galactic time that several races sent observers to the outskirts of the newly discovered sentient system.
And it was not too long after that, that Earth observers began to detect unusual movements out in the neigborhood of Neptune.
At first it was explained away. “Just some more planetesimals stirred up by Neptune's orbit.”
“Nothing out of the ordinary. A new comet or two. Add them to the catalog.”
But a few astronomers were tracking the objects, which were lit at times, unlit at other times, and moved quite erratically.
“No matter how much a planetesimal tumbles, it does not fly in formation with others, then suddenly break off and move in odd directions without any gravitational explanations.”
A couple adventurous races moved in closer, to get better visuals on Earth's orbiting ISS and Comsats. The NASA and RSA scientists who were tracking them tried to keep that quiet, too. But the story soon leaked. The sources were discredited, and the lid was kept on for the time being.
Military branches were informed, and brought out their “just-in-case” manuals. Variations on the “fire everything we have and pray” strategy were reviewed. Governments consulted with each other. It was decided that as long as the 'bogeys' didn't make any outright hostile moves, we would observe. After all, we might learn a thing or two.
A probe was discussed, between the Europeans, Russians and Americans. After much haggling, it was agreed that a set of two probes would be sent. Cameras, radar and radio sets. But no identifying marks. After all, it was reasoned, if they are watching us, we certainly have a right to watch them back.
The 'bogey” movements slowed, and soon they blended in perfectly with the background. Someone on the other end got the rogues to cool it, and folks were just watching for the time being.
They followed the Earth probes with interest. They even allowed them to bathe the ET's with radar, lidar, and a lot of other “ar”s. Eventually, the probes journeyed out into the Kuiper belt and beyond. They sent back data that was inconclusive at best. But at least the Earth agencies got some more good close-ups of Pluto.
Earth became a de-facto galactic petri dish and/or zoo. As life went on down on terra firma, the space agencies would have periodic spurts of exploration, followed by decline. Funding and accidents were blamed. Planned Mars colonies never quite got off the ground, and the Moon was exploited, but only with robotic devices. People contented themselves with the usual mundane pursuits, and human life went on.
When this or that pair of lovers would take a hand-holding walk at night, and look up at the stars, and wonder about their fates and how they became intertwined, little could they know.
Their fate was not in the hands of gods, kings, presidents or corporate potentates. The zookeepers were mostly to blame.