My older brother and I were heading out of San Antonio to spend the night hunting for snakes northwest of Del Rio TX. We were approximately 10-20 east of Del Rio heading westbound on HWY 90. We usually try to make it out there earlier in the evening because we like to watch the airplanes doing touch & go's at Laughlin Air Force Base. This particular night we got a late start so it was already dark before we got there. As I could see the shine in the night of the city of Del Rio off in the distance I knew we were close to Laughlin AFB. My brother and I had been listening and laughing along with the satelite radio comedy station and weren't really conversing about anything for a few moments. He was driving and I was sitting shotgun. A light above Laughlin AFB caught my attention. It was a very bright green light. Kind of liike an LED bulb. It didnt seem to emit a lot of light either, much like an LED. As I looked at it all these thought ran through my head. Hmmm, thats awfully tall for a cell phone tower? Wow its really bright for being so far away. I'm surprised they would have such a tall tower next to an airfield with so many planes buzzing around. I've never seen a green bulb like that on a tower... Before I could lift a finger to point it out to my brother the object darted across the sky so fast that it went from my 8 o'clock to my 1 o'clock in the blink of an eye. All while being several miles away. I figured it traveled about 15-20 miles in less than half a second. After the object darted across the sky and stopped in an instant, it sat in the same spot for about 5-10 seconds and then light slowly faded out and the object was no longer visible. My brother and I immediatly looked at each other and simultaneously said,"Did you just see that?" All these years I figured it was some kind of military experiment. I finally decided that if it wasnt military property then someone should be made aware of what we saw...