WHAT I SAW DRIVING over the 520 bridge right now. The bridge is dark and there are low/no lights in the area because of its affluence and above the stadium (stadium is background). I was driving and my riders (I'm an UBER Driver) and heading West toward Seattle and it was completely dark. All of the sudden out of no where, I saw a huge (without knowing how to describe it) Meteor or similar go across the sky at a rate of a 5 count using your arm extended from left to right. it was 100m above Laurelhurst and glowed green. As it shot across it look like a triangle with white phosphorus front edge because of all the sparks flying across the front. It was extremely visible the distance was 3/4 thousand feet but in front (above) of the UW stadium. It was very radiant and In the middle it glowed very emerald distinctive darkish green (so much so that the water and trees also glowed as it streaked) and had a comets tail the length of my index finger (including the front). The size would be a golf ball outside my wind screen about a couple feet out.. The trajectory was north eastish based on what I could tell in the direction I was going and it looked like it could crash in north Seattle to almost lynwood because it was losing altitude.The most interesting thing was that its speed was fast, but not meteor fast and at that distance would actually be quite slow. My riders didn't see it because they were drinking, but when I screamed "LOOK", they were trying to find it, but it crested the horizon.What I can say is that the clarity of the object was amazing and the color was pretty spectacular. In the triangle was a dark green, outer triangle whitish green, the comet look in front of it like something entering the atmosphere was white phosphorus and sparking like a welders tool against metal and the tail was white.I never posted like this before, but please tell me that I wasn't the only person to see this!