Two "satellites" travelling south in tandem, then reversing direction and travelling north in tandem, then diverging.April 19, 2017, Approximately 9:45 pm local time.Location: Cobourg, Ontario, Canada Visibility: clear.Facing east, observed what appeared to be two satellites, moving in tandem, one behind the other, in a due-south direction, approximately 45 degrees between horizon and zenith.Distance between lights approximately that of Mizar and Alioth of the Big Dipper (Big Dipper was conveniently directly above sighting).No sound.Approximately one minute later, both lights were seen travelling in opposite direction, due north, along same trajectory, again in sync but perhaps further apart.Through binoculars, could follow both clearly. Gradually the lights diverged, one continuing due north, the other heading north-east until both faded from view.Observer is a recording engineer with background in printing and publishing. Has also observed a sighting in same location in April 2011, where there were three lights in V-shape travelling at high velocity due west.