Now imagine an intelligent civilization arises on the surface a habitable planet in the runaway system. Their astronomers would gaze out into an inky black starless sky. True, there are stars in the Milky Way's halo, but they are so faint that only a chance nearby passing star would become visible. Globular star clusters in the Milky Way's halo would pepper the sky, looking like tiny cotton balls.
The bright nucleus of the Milky Way would look like a fuzzy headlamp. The ghostly faint tentacles of the spiral arms could be seen winding out from the nucleus. They would sprawl across a huge swath of sky.
Alien sky lore would have no constellations in the absence of stars. All mythology would be built around the nighttime wispy pinwheel with its cycloptic "glowing eye." Alien sky watchers would duly note the appearance of brilliant star-like novae and supernovae in the spiral disk. These might as first be construed as omens or messages from the gods, or fuel other superstitions. But fireworks in the galactic disk would be dutifully recorded.
The development of telescopic astronomy would allow star clusters and nebulae to be resolved. It would be as big a revelation as when Galileo first observed the Milky Way in 1609. Bright blue stars would be seen sprinkled across in the Milky Way's spiral arms. Spectroscopy would show that the pinpoints are made of the same stuff the alien's parent star is. But it would take a great leap of imagination to connect the tiny pinpoints to the brilliant glowing orb of their star.
Only the alien equivalent of an Einstein, Newton, and Galileo rolled together might have the conceptual breakthrough that their system is the oddball outcast in a universe of myriad stars. This might get the scientist burned at the stake as a heretic.