It is the most burning question of human beings today. Could there be life on other planets? There has been much debate throughout the history of mankind, and different sources used to either credit, or discredit the possibility. While most of the debate has been most philosophical throughout history, we now have the technology to look out into space, and see more clearly what is out there.
The universe is so big, that just by accident there should be more than one planet that has life on it. Unfortunately, even with space probes traveling at 25,000 MPH out toward the edge of the solar system, we aren't likely to see our probes meet up with any other civilization anytime soon. With the sheer space that exists between stars, we couldn't possibly hope to find one in our lifetime unless they came to us.
So is there a civilization out there looking for us? I don't see why a civilization would be looking for us. A minor planet in a minor solar system on the fringes of the galaxy. It would be like going to New York City and looking to find some last place minor league baseball team, instead of trying to find tickets to the New York Knicks.
In the 90's a piece of rock was found in Antarctica that supposedly had some sort of Martian biology on it. So far that is the best evidence we have of possible life on other planets, and that evidence is dubious at best.
Outside of that, all we have is some possibility that Mars was once wet, and possibly there is methane caused by biology on the surface. We have Europa, that contains a theoretical ocean under its surface, yet we won't be able to see what is down there for quite some time.
Taking into account the Drake equation, we can speculate that an average, there are 50 different civilizations that are currently active in the galaxy. We also know that a planet orbiting another star may be within that stars habitable zone, or within the area in which it is not too close to be too hot, but not too far away as to be too cold either. Gliese 581D is speculated to be in the habitable zone of its star, and therefore may be able to support life.
Is that life intelligent though? Most likely not, as most life on Earth cannot do even a fraction of the things that humans can, and nothing before us could match our intelligence either. So that assumes that if life can arise, will it be smart enough to communicate to the rest of the universe? Again, even if it could, it would take some time for the signals to reach any other civilization.
So for now, we will just have to speculate on whether or not life could arise on other planets. While it sounds logical that other planets could support life, we don't know for sure yet. The bible says God created us, and only us, so maybe it isn't so crazy that other planets don't have life. Fortunately, science allows for the evidence to speak for itself, and hopefully we will know the answer one day.