Even with all of the advancements in modern technology, we still havent made contact with intelligent life on other planets. But what if our attempts to communicate have been ignored?

In 1973, a radio astronomer named John Ball came up with a possible theory as to why aliens if they do exist havent gotten back to us. Balls Zoo Hypothesis as it came to be known, posits that alien civilizations exist, and the most highly developed of them have been communicating. This elite alien club has come upon a mutual agreement to leave those deemed primitive or lesser life forms alone, only to be watched from a distance. Earthlings, therefore, did not make the cut with the galactic cool kids.

So assuming these aliens exist, under what circumstances could they all agree to keep us in the dark? A Scottish astronomer named Duncan Forgan has the answer.

I was interested in this theory because it is so difficult to test in a scientific fashion, Forgan told FoxNews.com. The Zoo Hypothesis relies on us being unable to observe other aliens, so a failure to observe aliens can be used both as evidence for and against the hypothesis at the same time!