Harvard professor explains we may have ALREADY been visited by aliens for THIS reason ALIENS may have already visited Earth without us even noticing, according to a top Harvard professor. Share: Facebook Twitter Google+ Stumble Digg Email ThisBlogThis!Share to XShare to Facebook Related Posts:Humana Plans to Pull Out of Obamacare’s Insurance ExchangesIntel Drops Its Sponsorship of Science Fairs, Prompting an Identity CrisisDownside of Being a Global Hub: Invasive SpeciesTrilobites: Ancient Jars Hold Clues About Earth’s Fluctuating Magnetic FieldsFirst actors, then Sixties pop stars, now it's British SCIENTISTS who are invading AmericaDubai Plans a Taxi That Skips the Driver, and the Roads