It's neither a hoax not a UFO. It is electrically charged ball lightning, attracted by the electrical field of the huge generators moved into the Temple Mount on January 25th after being donated by the Jordanian government. The flash of light is likely arcing caused by a short circuit in the generator. This cut off the power it was generating. The only electrical force left was that due to the electric field extending between the ground and charged clouds. This force made the ball lightning (a ball of electrically charged plasma) fly upwards.