Former NASA Apollo astronaut Edgar Mitchell is once again claiming that we are being visited by aliens and UFOs and that the government is covering it up. As a science fiction writer and fan, and as one who has been captivated by the marvels of the universe since I was a boy, my initial response is how I wish it were so!
But wishing does not make it so.
Observers of the universe–scientists–have a method for learning the truth. Or better yet, they have a method for learning what is not true. In simple terms, after making observations, you develop a generalization or hypothesis, and then test that hypothesis against the evidence to determine its veracity. There are two key parts to this last step. First, there has to be evidence against which to test. Second, the test has to be reproducible by others.
Not a single claim of aliens visiting the earth has ever passed either of these tests. UFOs perhaps, but not aliens.
We get reports of UFOs all the time, and indeed they visit with some regularity. They are exactly what the moniker that describes them indicates: unidentified flying objects. Sometimes, they are ultimately identifies as meteors or satellites burning up in our atmosphere. Sometimes they are identified as military aircraft or weather balloons. Sometimes, they are not identified. However, there is no logical leap that I know of that equates “unidentified” with “alien spacecraft”.
Claims of aliens visiting the Earth are more outlandish. Eyewitnesses often speak of evidence, but cannot produce any. Testimony that might hold up in court, does not always meet the strict standards of scientific methods (if it did, we would probably not need a Project Innocence program). More often than not, the “evidence” is nothing more than an eyewitness report. As much as the person who witnessed or experienced the event wants to believe it, science cannot take such claims at face value. There are far too many variables in the human psyche, to say nothing of the fact that there is still nothing that can be tested and reproduced.
Most scientists would probably agree that the chances of other intelligent life in the universe is very likely. But the very assumptions that make conditions for intelligent life likely, also make it unlikely that such life has visited Earth. The Drake equation estimates 2.3 “star-faring” civilization in our galaxy. Given the size of the galaxy, and the distance one would have to travel, it is very unlikely that any of those other potential civilizations have made it this far. Furthermore, the odds are incredibly slim that they would find us in the first place. Assuming they were too far away to detect our radio signals (so far), the chances are astronomical that they would blunder upon our planet.
Regardless of how advanced a civilization you are, star travel is expensive, not only in terms of money, but even more in terms of energy. Such an advanced civilization (one that has made it past the point of destroying itself) would have far more efficient ways of searching the stars for other intelligent life.
When I have argued this in the past, people often come back with the fact that these civilizations may be so advanced that they have technology far beyond our means and that technology could dramatically speed up their travel time. Maybe so, but there is a universal speed limit–that of light. Even at light speed, it could take 100,000 years to cross the galaxy–and for what? To tease humans with crop circles and alien abductions?
Maybe the aliens can travel faster than light. FTL is a trope of science fiction, and while it’s fun to read about (and write about), our current understanding of the nature of the universe makes this impossible.
Maybe the aliens understand the universe better than we do. Undoubtably, particularly if they have been able to survive self-destruction. But the observations we have made of the universe hold true for the entire universe. Aliens might develop cold fusion to power their spacecraft, but they cannot bring that spacecraft beyond the speed of light They live in the same universe we do.
Contact with an alien civilization would be a monumental event of human history. No government on earth could cover up such an event. As much as I wish it were true, I don’t believe aliens have ever visited the earth. When all is said and done, I could be wrong. The fact is, the only statement I can accurately make is that there is no evidence that aliens have ever been to earth. Until there is evidence, it doesn’t matter if they have or haven’t.
It’s this point that UFO enthusiasts like Edgar Mitchell fail to see.