The fact is that von Däniken (whose writings much of the History Channel's show is based on) has been proven to be a fraud. For example, he produced photographs of pottery allegedly from an archaeological dig dating back to the biblical era which supposedly depicted ancient UFOs. In 1978 a Horizon/NOVA documentary traced the origins of the pottery to the guy who von Däniken paid to make it. von Däniken admitted to the fraud but claimed he had to fake it because it was the only way some people would believe his theories. He also claimed to have been guided through artificial tunnels under Ecuador containing gold, strange statues and a library with metal tablets, yet when Der Spiegel tracked down the man who von Däniken claimed was his guide, he denied ever showing von Däniken anything and stated that the photos in the book had been "'fiddled." von Däniken also admitted to this, saying he had to do it to "add interest to the book." BTW, von Däniken once served a prison term for fraud, so it's not like faking stuff is anything new to him. And yet this is the guy at the center of The HC's so-called documentary?

Look, maybe aliens really did visit ancient civilizations, I certainly can't prove they didn't (nor can anyone else), but this recycled garbage science that HC is trying to pass off as legitimate have been shown on many occasions to be fraudulent. More to the point, it isn't up to anyone else to prove something didn't happen, it is up to the people making the claim to offer valid evidence, which IMHO they have utterly failed to do.

There is nothing wrong with keeping an open mind, unless it is so open your brain falls out