Originally Posted by Johny Traffic

No
if you are asking, do I think that people who look exactly like us (but green) with two arms and two legs are driving zillions and zillions of miles in space ships that look conveniently like we envisaged them in sci fi movies.... and have arrived just at the one brief moment in time that humans are alive on our planet and that is the explanation for someone seeing (or not) a big shiny round thing in the sky.

Then no.