Well, I don’t believe in aliens simply because we should have by now received some form of transmission whether it is an alien version of “I Love Lucy” or radio signal, even if it is very weak. Not to say alien life is totally out of the question, it is possible of finding planets with similar atmosphere with perhaps plant life and lower animals. I do believe that God in His infinite mercy and grace has created additional worlds for us to settle upon, so that we can spread out unto new worlds, so we may be fruitful and multiply.
Some people think that it is such a large universe that it is inevitable that intelligent extraterrestial exists, however we live in an extremely fine tuned universe and the conditions that are required for life are probably rarer than we think.
Personally, if any of these ufo’s are real, I don’t think they are extraterrestial, here goes the science fiction here, but I think they could be humans from the future, because based on what I hear from so called abductions, it seems to me that more advanced humans from the future has lost the ability to reproduce naturally, so they come back in time abduct people, abstract DNA and whatever else they need, produce ‘hybrids’ and return to the future in hopes of preserving humanity.