Originally posted by institute
Looking at images like this makes me amazed at how some of us think that we are "alone" in this universe.
I'm not really sure how many people really think we are the only intelligent life in the universe. I think most people feel that there is some other
life out there somewhere in the vastness of space, perhaps asking the same questions we are asking about possibly being alone.
However, I think "alone" could be thought of as a relative term. Think of a person stuck on a tiny desert island. That person could be considered to
be "alone" and go unnoticed
by the rest of the world, even though there is a world of people beyond the island's shores. Earth may be like
that desert island: a tiny part of a vast universe with other beings on other worlds, but still basically alone in that vastness because it can so
easily go unnoticed.
And before someone says "we can't go unnoticed -- they can detect us by our radio broadcasts", please be aware at how tiny the volume of space is that
our radio broadcasts have ever reached. We have been sending out radio broadcasts for only about 100 years (and TV broadcast later than that), so
that means the sphere or bubble that those radio waves have traveled so far is only 200 light years (LY) across.
This image shows a representation of our Milky Way galaxy, and the total extent of our radio broadcasts. That tiny blue dot is how far our
"intelligence" can be detected through radio. Some other alien species would need to be inside that blue dot from them to detect our radio waves to
notice we are here. It's quite a miniscule area -- especially considering that this is only showing our own galaxy. Our galaxy is only one of
hundreds of billions of galaxies. Considering the size of the universe, that blue dot is so tiny, it borders on being non-existent.
It may be true that there are other remote ways of determining that intelligent life may exist on earth -- such as by doing a spectral analysis of our
atmosphere and finding that we are burning fossil fuels (i.e., an industrial society), but even that would have only should up in our atmosphere about
250 years ago, and the light from our "industrial age" atmosphere has only gone as far as a 500 LY bubble -- which is still miniscule.
What I'm saying is that there may be other intelligent life out there, but unless they notice we are here, we could may be able to think of ourselves
as being "alone", just like the man on the unnoticed desert island would consider himself to be alone, even though he knows other people exist in the
world. For all intents and purposes, we may very well consider ourselves to be alone until some other race notices us (or vice versa).
source for above image:
How far in space our radio broadcasts extends?
edit on 6/12/2013 by Soylent Green Is People because: (no reason given)