The question isn't whether there is one, but whether there is one within communication range. The one hundred billion galaxies that we are aware of at the moment are each huge as well, making finding a civilization within one the proverbial finding a needle in a haystack. Beyond that, the nearest galaxy is 2.5 million light years away. Even if we find a way to communicate exclusively through light, it will take millions of years just to send and recieve a simple message. And unless we find some way to get around the whole "nothing can travel faster than the speed of light" problem, we're certainly not visiting there.

^ that.

Useing light to communicate... okay.... useing suns to make that light, to communicate with... holy f***.

I think Star Trek has it right.... dont start mingleing with speices that dont just have warp capabilities figoured out yet.

Once we start testing warp speeds, vulkans will come save us (from ourselves).

Lets not attract the attention of these beings that play with suns for funsies.

These specific signals will probably not come to much, but I'm about 99.99 % certain that not only is there life beyond the solar system, but that it is, relatively speaking, plentiful. Now, as MTZ said, that may not mean there is another civilization capable of communicating positioned closely enough to exchange any sort of messages with us, but life itself is probably fairly common. 

Well, I think a lot would change actually. On an emotional level there would be worldwide astonishment despite however many already "believe" The more tangible evidence that comes our way the more tangible our amazement becomes. The amazement is more of recognizing how incongruent our former belief systems were in general - simply, not being alone.

From there however comes the real turning point imo. Something of that nature, whenever we reach communication that is, would give people a more long-term vision of life on Earth and in space. The exact kind of long-term thinking necessary for taking actionable steps to secure the health of this organism we call Earth.

Denial of Gloabl Warming, imo, is not really about religious nuts so much as it is about a short-term thinking mentality that we have yet to rid ourselves of biologically. It was necessary in the Cave-age, but now no longer.

Classic case of looking at key points to prove a desired truth rather than looking at all points to determine a universal truth.

Yes their biology could be completely different but if still carbon based I'm sure there could be insects, microscopic life that we have no resistance to. Life is a delicate balance of new strains of viruses, bacteria vs larger animals immune system.  Present a bacteria that causes a immune system shock, is highly poisonous, more effective in our atmosphere. I suspect if two animals meet evolved from 2 different planets one will be susceptible to the other. Yes viruses seem less likely to be effective but viruses are constantly mutating with each new generation and our viruses are something like 20 minutes to 2-3hrs per generation. 

Admittedly though aliens are much likely to be exterminating us so they can make use of our resources. All aliens will have evolved on planets where creatures have to consume each other to survive. They will be I'm sure used to killing on their own world.  We like to think of ourselves as civilised but lets face it you only have to look at an abbatoir to see the true horror's of humanity.

I think it will go the opposite way. I mean if the aliens were able to spread to multiple solar systems there is absolutely zero point to conserve this planet. It's just one of literally billions.

So you will have less global warming deniers but a ton more global warming whogivesafuckers.

Yes, but there's a lot of variation in what life could be out there.... The Fermi Paradox is pretty set on the likelihood of organisms out there, especially give what we know about Martian life.

For advanced intelligence, its hard to say if there's a Great Filter or not.

This! This is very important. There will be countless amount of things that will change and will need to be changed if humanity wants to have a future not just in the universe, but sustainable here on Earth. For example a lot of currant "points of view" will no longer become a matter of debate. There will come a point where we can no longer isolate ourselves. Once we leave our planet, we are in a domain of a greater community. As far as our planet goes. We may one day need aid, or to expand/leave when Earth becomes inhabitable. And yes, we will likely be required to have a one world government or a World Council to represent out people in the post contact world for a long list of reasons that could prove to become disastrous.

The short term mentality is going to cause a lot of issues. Currently it's already preventing us from making leaps in human advancements and tackling issues we already have here on Earth. Imagine what will happen when the whole world becomes aware of this reality should it be the case?

 There has to be. Most of the moon's surface is literally covered in an ocean under all the ice; there's no way you could have that much water and no crabon based life forms living within it.