a green fizzing ball the size of the moon travelling low and fast in the night sky ..

i just got home and turned on the t.v and out of the corner of my eye their was a light in the sky traveling, it was low in the dark sky , the size of the moon , greenish colour round shaped, and fizzing , it seemed about a mile or two from me , it must of crossed Birmingham airport but when i seen it , it was in chelmsley wood area , i had a clear view of it as i lived in a tower block at the time, it was heading towards castle vale , and sutton coldfield .i thought it was a flare at first , green , fizzing but then thought flares dont travel across the sky  horrizontal at a constant speed for such a distance and speed was to fast  i estimate it was travling at a aircraft speed 400 or 500 an hour, i wouldent say it was an metior it looked low in the sky as if it could crash in birmingham and proberley did , i thought it could of been a milatary weapon ( flames of the tail end of a  war plane or missile , though i heard no noise ) my best guess is that it was a cruise missile was  being tested as the gulf war was not long after , or may be it was something else it was something ive never seen before and never forget.
Witness indicates that the date of the sighting event is approximate.  PD