It was like a green laser through the sky but very straight and had high resolution. I thought it may be a laser on the clouds (minor cover) but if it was, I would have seen more. I had been outside my work in the car park talking for about 15 min prior to the sighting and for 10 min after. I was always facing that direction. If someone was playing around I would have seen it more than once. It looked like a rectangle with a blank line through the middle. I have seen many falling stars before. This is the 3rd most amazing one I have seen.