2 dots of light streaking to the northwest with unusual movement.

Sitting on the roof deck with an unusually clear sky, we were watching satellites quietly cross the heavens. Then i noticed 2 objects moving rapidly toward the northwest. the objects were moving back and forth in an elliptical motion. they traded places in the lead position without ever crossing. they traded places at a rate of approx. 1 sec.
i do not believe this was within the earth's atmosphere the sun was clearly hitting them, as it does satellites.
when i first spotted them, i yelled "what the hell is that?" and pointed. my wife was easily able to spot them to the left of the big dipper and follow them with me until they disappeared.