well, as for why would aliens take an interest in us at all? richie1234 said its like people and ants...the average person doesnt take an interest in them. well, the average person may not, but hundreds of scientists around the world study them (and everything from humans to single celled organisms) every day. "IF" they are out there they would be as interested in us as we would be in life on mars. we sent the rover there for the sole purpose of finding out if there was or ever had been life there. imagine how much research would have been done if we had found so much as a 10 million year old fossilized bacteria, or plant, or intelligent life??? I dont believe the whole anal probe story, and I dont beleive that 90% of people who claim to have been ubduvted by aliens really were. however I do believe they have atleast flown over. and flying millions of light years isnt that far fetched. 100 years ago we KNEW it was impossible to fly, let alone get to the moon, or create a new person from a single cell. it is perfectly within the realm of possibility for life on another planet to be more advanced than us, have the ability to travel far faster than modern scientists believe possible, and to think coming here is worth it. how many billions of dollars did it cost to send the rover to mars, a dead planet, just to take some photos and videos and pick up some rocks??? imagine if one of our deep space probes found a planet seemingly identical atmospherically (or otherwise capable of sustaining life) just outside our solar sytem. what lengths would we go to to travel there to study it?
I also beleive area 51 has/had an alien craft. when it supposedly crashed the air force announced that it WAS an alien craft, then it was a weather balloon, then alien craft then weather balloon. in the early nineties in new england it happened again. announced it was a alien craft, weather balloon, alien, weather balloon. and was it in the 70's that several hovered over DC? one right over the white house, president or pentagon dispatched fighters to chase them off or shoot them down. fighters got to dc and they were gone. as soon as they touched down back at the air base they got called again cause the ufos were back. the pilots claimed they were travelling at speeds and directions impossible, and chased one along the patomac, then they left, striaght up into space. there were too many witnesses to cover it up and the pentagon still has no answer to what they were, didnt even attempt to hide it or say it was experimental spy planes or anything. airline pilots and air traffic controllers have seen them, theres just too many witnesses to say all of them are liars/crazy.
we know today that it is possible to terraform a planet (for instance give mars an atmosphere and create forests and life) but with modern technology it is currently impossible, and according to researchers even when we finally can develop the technology it would take hundreds of years to complete a terraformed planet. how do we know that billions of years ago some alien race wasnt experimenting with terraform technology, and created earth? or made it livable? or found it during primordial stage or even dino age and seeded it with their genetic material? chimpanzees are one chromosome away from humans...maybe we are one chormosome away from some alien race?
just saying, ANYTHING is possible. I myself am happy to live my daily life and never give any of this any thoughts except at times/conversations like these. and I am also perfectly content to never know the answers to any of these supernatural and.or extraterrestrial questions. ignorance is bliss, and leaves room for the imagination.