I was coming back from the supermarket, walking on the side of the street, when right in front of me this very bright phosforescent electric green fierball cross from east to west. It was not falling down, it was flying parallel to the ground. At about 50-70 meters (150-200 feet)above the ground, It was about 10 meters or 30 feet of circunference, the ball was almost white in the middle, and green in the sides, and it had a small "tale". It didn���t make any kind of sound, and what I think was very peculiar, was that it did turn on and off radically, is to say, imagine seing the fireball flying across and then put something between your eyes and the ball, so you cant see it. Then take it away very fast, then put it back on.. I hope this example helps you to understand my explanation.. and by the way forgive my english.this happend very fast, but I cuold see it very well, and it was close to me. This happen in january 2005. In january 2009 I saw it again, but this time it wasnt geen, it was blue.. Phosforencent bright electric blue, it was just like the first one, the same size, the same speed, it turn on and off just like the other, but it was blue. This one I saw it in Hato El Cedral, a wildlife refuge in the South-west of Venezuela.When I saw it the first time I was impressed, I knwe it was a UFO, it was not normal, it was not a metiorite, because they fly down to the ground.. this thing was "flying". The second time I saw it.. I felt relax.. It was like. ey here they are again...