You have to think about the whole UFO theory seriously and in great depth. By UFO, i refer not to the actual meaning, but the suggestion of Alien ships that has been built up around the term. Now, i don't deny something is going on, but if we look at the evidence and think reasonably, then Aliens become a tad ridiculous in terms of an explanation.

Firstly, we know that some sightings will be of experimental aircraft being tested by the Government. That is a given. Other sightings can be explained by: misidentification of civilian aircraft; meteor activity; and a number of atmospheric conditions. All valid explanations, not to mention that the people could just be lying.

If there are so many Aliens whizzing around our planet...why do we not have some artefacts from them? Why no good images? Why would they even bother whizzing around and trying to remain secret so...badly?!

It seems to me that we have people creating a modern myth. The UFO community are building themselves a different kind of Religion. It is certainly interesting, but it is not really that valid. How come they look so like us? Do you know the chances of that happening? Extremely remote, basically. You might argue that they manipulated our DNA in a past time. However, if they did so, they are not very good at it. Certainly not as good as they should be, if they travel between the stars more effectively than ourselves.