Witnesses may be wrong, but if approximately 100 witnesses describe the same thing, then unless you believe there has been some collusion or influence among them, this makes for fairly strong evidence. Otherwise, the only way so many witnesses could have been "wrong" in the same way, is due to a shared, and incorrect, interpretation of what they saw.
If this is true, how do you explain the 1,000s of Americans who have seen flying saucers...and the hundreds who have been on board them.