The Fermi Paradox
I came across this article late last year and was totally amazed by it and the ideas that it put forward. If you like astronomy, stars, aliens and anything to do with the Universe, have a read via the link below. It may possibly turn out to be the best blog post you have ever read, it certainly was for me! ENJOY!
http://waitbutwhy.com/2014/05/fermi-paradox.html