1. They are to far away to reach us
    2. If they have technology which would make it possible for them to travel faster than light, they have such high intelligence that they don’t recognize us as intelligent beings like we don’t recognize viruses as having any intelligence, so they would never think of visiting us and communicating with us.
  • All of this is layman with some basic understanding only.

    So, on the one hand in our galaxy alone there are between 100 and 400 billion stars (wikipedia), now a lot of those have no planets, but of course a lot have many more than our system does. So at least the same number in planets. There’s a good chance there’s more than one planet capable to supporting life among that number.

    In fact as we improve our ability to observe our galaxy we are able to verify more and more viable planets and even a reasonable number that are similar to our own planet.

    This means that there’s definitely going to be a reasonable chance that somewhere, life has evolved to similar or beyond our level already.

    But, this for sure doesn’t mean there’s any reason to expect visitors. That’s because even if they can travel at the speed of light, it’s still going to be thousands of years for the majority of them to reach us, provided they even choose to come to us. Because, from where they are they wouldn’t be able to make out our radio signals, nor likely any other signs of life. So we’d be one of many “potentially live bearing” planets.

    So, just my opinion. I think the chance of life being out there is reasonably high, the chance of actually being visited (assuming it holds true that we cannot travel faster than light) is probably very very low.

  • The universe is so unimaginable large and there are so many stars and planets that there are good chances of the existence of extra terrestrial life, but at same time there is a very small chance that they can find us, even if they are advanced enough to search for life in the universe. If they are much more advanced than us they probably don’t care, in the same way we don’t care to try to make contact with all the ants of the earth.

  • If there is life out there, it would be rather unspectular. It would exist in the form of microbes, probably not even visible by the human eye. There are theories that suggest that there is a high chance of life on Enceladus.

    One of the reasons that life could develop into complexity on Earth is that it could develop over the course of millions of years relatively undisturbed. There were no outside events like supernovae that swept Earth out of exsistence. The Primordial Soup could be cooked long enough to result in complex and intelligent life forms. Other places in the universe probaply have not that advantage, so that the development of life didn’t come that far yet.

    I suspect that there is a higher chance that life in other places of the universe will be tainted by humanity than the other way round.

  • I love Greg Bear’s take in the War Dogs trilogy.

    They show up but slowly introduce themselves, give us trinkets, coerce & exploit us , then after much happenings, leave and the world goes on like nothing ever happened.

  • Maybe we are part of an extra terrestrial being. Like the things on our eyelids or blood cells or anyother microscopic lifeforms that are part of our organism.

    In that case we are already in contact. So maybe an autoimmune response will be the next step.

  • There are so many pessimistic comments.

    To those who are saying, something along the lines of, aliens wouldn’t come because they wouldn’t recognise us as intelligent.

    That is a really stupid augment, even if they were significantly more intelligent than us, we still standout from all other minds on this planet.

    We literally study everything, just for the sake of knowledge.

    A high intelligence civilisation that has the ability to reach us, would also have to a high level of curiosity to archive that ability.

    To answer question posed. There are two ways to look at this:

    • if we assume that, at some point an alien civilisation will contact us, the next 10 years is as statistically likely as another ten year timeframe.
    • from a background rate, of the actual likelihood of being contacted at all. I have to say, it is exceptionally unlikely. The travel distances/times, and the time a civilisation exists for, all count against contact especially physical contact.