But space is very large, and if LIGO scientists could pinpoint their search, they might detect those ripples sooner. Also, should they detect them, they will need to match that data with telescope observations of the merger event to confirm.
This is where Kelley's recent work can help: his findings suggest that the galaxy catalogs currently proposed as a means of following up on potential gravity wave detections need to account for some unusual behavior if they're to be useful for confirmation. And the scientists might want to look beyond the nearest galaxies.
See, compact binary systems - pairs of neutron stars, black holes, or one of each - don't just spiral around each other, they are also speeding through space.
"By the time the two objects merge, they are likely to be located far away from the galaxy where they were born," Kelley said in a press release announcing his results. That's because they get a sort of recoil "kick" from slight asymmetries in their parent supernova explosions - in the case of a compact binary system, the maximum velocity would reach 200 kilometers per second. That means when the two stars finally get around to merging, they could be far away from the galaxy of their birth - good news, as it happens, for optical confirmation.