Glowing Orb UFO Filmed Over Portugal (Video)

A greenish-silver, glowing orb UFO, which is not a star, was caught on tape in the skies over Barcelos, Portugal as a graduation ceremony was being filmed. What is it?

The video of the unidentified flying object sighting was taken from the crowd of a group celebrating a final graduation ceremony and sounds of the revelers are plainly heard in the background.

High in the sky, the videographer noticed a glowing, greenish orb which just hovers in the air, motionless. It cannot be any kind of star as storm clouds hang low overhead, so whatever this object is, it's well below the cloud ceiling.

The UFO seems to change color from silver to green as the camera zooms in for a closer look. An enhanced image shows it is definitely not a bird and doesn't look like a plane or helicopter. It has no running lights, no wings and emits no exhaust fumes.

So, what is it?

Here's the video: