SAW BRIGHT ORANGE FIREBALL CROSSED SKY LEFT TO RIGHT IN FRONT OF CAR..LOW AND BRIGHT FOR 5 SECONDS LEFT TO RIGHT. EXPLODED TO BRIGHT GREEN LIGHTING SKY AS WENT DOWNWARD BEHIND TREELINEWE WERE DRIVING WEST ON HW 72 ABOUT 10PM ON 8/2/97. ABOUT 1 MILE BEFORE THE INTERSECTION OF HW 15. A BRIGHT ORANGE OBJECT WAS OBSERVED ABOUT 20 DEGREES ABOVE THE HORIZON, GOING LEFT TO RIGHT. TOOK ABOUT 5 SECONDS TO CROSS, BURSTING TO A GLOWING BRILLIANT GREEN AND DESCENDING BEHIND THE TREE LINE ON THE HORIZON. WE LEARNED LATER THAT THIS IS NEAR WHERE THERE WAS NASA FACILITY BEGUN BUT NEVER OCCUPIED AS GOVERNMENT FUNDING WAS CANCELLED?? I WILL NEVER FORGET HOW BRIGHT IT WAS AND LIT THE SKY. IT MAY HAVE BEEN FAR AWAY BUT DIDN'T SEEM SO WHEN WE SAW IT. IT WAS LIKE OBSERVING A COMMERCIAL AIRLINER LANDING FROM SAY A MILE AT MOST..BUT THE COLORS WERE SO BRILLIANT AGAINST THE PITCH BLACK SKY THAT NIGHT.