Since the SETI program first began searching for possible alien radio signals a few decades ago, there have been many false alarms but also instances of fleeting signals of interest which disappeared again as quickly as they had appeared. If a potential signal doesn’t repeat itself so it can be more carefully observed, then it is virtually impossible to determine whether it is of truly cosmic origin. One such signal in particular caught astronomers’ interest on August 15, 1977. The famous “Wow!” signal was detected by the Big Ear Radio Observatory at Ohio State University; it was thirty times stronger than the background noise but lasted only 72 seconds and was never heard again despite repeated subsequent searches.
They have been here we just didnt know itThe Fugates are for realhttp://is.gd/PKYebR
I saw a flying saucer once, but I ducked just in time.
In terms of bacteria I think its highly likely. As for more developed life well there is a chance but I don't think it will be teaming and also if there is communication chances are so low given the distances involved.