Several years ago, my husband and I was setting out on the back porch under a awning on a swing, late night. The object appeared from the North east at a high rate of speed. There was a floresent electracil light from the back of the object and there was no sound other than a swish. It came to a complete stand still over our back yard and we were surprised. The object was triangle in shape and the green light slowly went out and a floresent white light was across the front. After looking at it for a few minutes and wondering what it was I stood up. You could see it rock back and forth but still no sound. Shortly after I stood up the lights went out just like someone turned them off. It still stayed over our back yard for a few more minutes then we heard another swish and it took off really fast. It went north west toward Goodfellow Air Force Base. I do not know how it could stay still up there without falling other than the rocking motion, might have had someting to do with it. I am still wondering what it could have been. It was dark so I could not tell what the bottom of it looked like, only the outline of it. We both didn't think anyone would believe this so I told only family up to this point. Not easy to put in a summary.((NUFORC Note: Witness indicates that the date of the incident is approximate. PD))