As wee reached the center of the bridge my friend and my daughter were looking our over the bridge (looking north) and suddenly told me to “look at that!” There was a bright white light hovering midair pretty much lined up with the bridge about half a city block out from the bridge itself. This light was roughly 5 feet in circumference and as our attention was directed at it, it started opening up in the center. my first thought was “omg that’s a wormhole! a dimensional portal!” It kept spinning and expanding til it opened up roughly 4 times its size,