A small star like light, making sharp turns in the area of Ursa Major (The Big Dipper)I was on vacation in Cancun, Mexico with my wife and 2 daughters, we had just returned from dinner and my daughters went down to walk on the beach, I went to the veranda to watch them.It was a fairly clear night and I was looking at the stars picking out familiar constellations, and was looking at "The Big Dipper",it was "upside down" with the handle pointing approximately east.From the NW I noticed a light that I assumed was a very high flying aircraft coming towards the Big Dipper,it passed between the 2 stars that formed the side of the "pot" and without slowing made a full U turn around the lower star and went back in the direction from which I first saw it, I called my wife and tried to point it out to her(she said she didn't know what I was trying to point out)and as I did so it made another turn back towards the constellation, then immediately turned back again, I lost sight of it as it moved back towards the NW.