Terry:
I suppose you could rank events according to some degree of distance from reality:
+++ Reality-Plausible-Possible-Impossible- - -
Reality is something that can be verified by others as a common experience. The more witnesses from a non-homogenous group the more likely a particular event occurred.
Plausible are the most likely explanations from a list of possible explanations.
Impossible events are those that are contrary to experience and laws of nature.
So alien visitation would not be at the top of a list of explanations for some bizarre event - it remains as a possible explanation if the more plausible explanations are eliminated.
Astrology is against known laws of nature. And it is statistically insignificant.
Six years ago my neighborhood experienced a very disturbing "jet-like - house shaking- roar that lasted 20 minutes. Others on a SW to NE trajectory experienced the event too.
So I checked reality. I interviewed neighbors and others along the route. 12 people in five different households experiecned the same "frightening" noise. It was a noise from above but there was no visible source although it moved in a specific direction. The sound went away abruptly after one witness claimed he saw a bright light (as big as a basketball and bright as the sun )shoot over the tree tops.
I called the police - there were no other reports.
I called the airport - there were no planes in the area at the time. Division of Noise abatement called and said other than engine testing at the airport (3 miles away) they didn't know what it could be.
VTOL (Harrier type Jets) were ruled out. To hover with full thrust for such a long time would be impossible.
Was the government testing out some kind of sound weapon? Decibels are easy to measure - why do it over a major city?
Was it a blimp with a 1,000 watt output speaker trying to freak us out? Awful risky, probably expensive practical joke.
Because all of these plausible explanations seemed unlikely - the idea of an extradimenional/extraterrestial cause moves up the list of possibilities.
It turns out that this particular event (loud roaring noise, sometimes reported to be associated with a huge ship of some sort) has happened close to a hundred times all over the earth.
On the particular night of this incident it was one of the bussiest nights of UFO sightings based on MUFON reports.
So what was it. You can't say conclusively. But, I know what 12 people witnessed that night. I know what I witnessed. I feel comfortable with an extra-dimensional/extraterrestial explanation. Does this mean that there certainly was such a cause? No! But it is more plausible than the conspiritorial explanations of "dark government projects". I tend to think more in the direction of an extradimenional source because the idea of traveling long distances from another galaxy seem highly unlikely.
I am not prepared to believe in Alien Abductions as reported through the intervention of hypnotism. But I am prepared to accept some common explanation for the type of experience I had which was characterized by loud jet sound (squadron of jets at roof top level) lasting more than 5 minutes to as much as 20 minutes. And some type of bright light visual associated with the whole episode.