

Tyson speaking in 2009 at the Apollo 40th anniversary event. Image Credit: NASA

Astrophysicist Neil DeGrasse Tyson has suggested that we may already be in a post alien contact era.

While SETI focuses its efforts on finding evidence of extraterrestrial intelligence out in space, there are some who believe that aliens may have already been visiting us for some time.In a recent interview with MSNBC, astrophysicist and Cosmos presenter Neil DeGrasse Tyson has put forward a third possibility, one that most of us aren't going to like. The concept centers around the fact that it is only by our own definition that we have determined what constitutes "intelligent" life in the universe."My great fear is that we've in fact been visited by intelligent aliens, but they chose not to make contact, on the conclusion that there's no sign of intelligent life on Earth," he said.It has long been speculated that our understanding of the universe may be severely limited by our perceptual capabilities. Perhaps to a sufficiently intelligent alien species a human being appears no more intelligent than an insect - a primitive life form barely capable of comprehension."The audacity of us to even claim we can define intelligence," said Tyson.