We came out of a restaurant about 10:30 pm, and as we walked to our car I looked up at the clear sky and stars and noticed lights moving very fast across the sky. They were not bright lights but steady, not blinking. They moved closer together, into a curved or boomerang formation, and continued across the sky moving from the SE towards the NW. There was no sound, the lights did not appear to be connected by an object, or the object was transparent. as you could still observe the sky and stars past it. At first I stopped to see if the lights were blinking in anyway, indicating a large aircraft, but the lights were steady. Appeared to be blue. I said to my husband, 'do you see that, what is that?' He looked up and caught it too and was surprised as well and could not decide what that might be.Lost sight of it as a building blocked our view. We walked past the fence to the alley but could no longer locate it.