On this day, 04/08/2015 I was working the night with my partner at the service station when we noticed a growing noise too loud and strong (like a jumbo), come see what it was but there was nothing in the sky, seemed to be floating, delizando down on the sky, as it was night did not see anything, only that loud sound like that of continuous propoulsao, we realize that continued as straight and disappearing slowly, very slowly, we saw some object but the sound was very strange. It was like a very large object itself was low flying around straight.We were many curious and try to follow to see if we could exergar something, but nothing was seen.That sound was in my mind long after also feeling that we were unprotected and defenseless. I do not know what houvimos but airline know it was not.We were so intrigamos that not even think about trying to record audio.