Extra-terrestrials

I had a question texted in while I was handling Q&A at Redux last Sunday. It read,

What are your thoughts on Aliens, scientifically and scripturally?

I'm going to assume that the questioner had in mind extra-terrestrials, as opposed to immigrants with or without legal standing. (I have thoughts about that, too, but will save those for another time.)

I guess this question encompasses several others. Is there intelligent life on other planets? If so, can it contact us? If so, has it? If not, what do we make of the reported UFO sightings and even those of actual encounters, including claims of having been inside of alien spaceships?

Let me begin my answer with a physics/astronomy tutorial. Some of the most fascinating (and relevant) research of the past several decades can be summed up in the idea known as the 'anthropic principle.' It was not all that long ago that astronomer and science popularizer Carl Sagan told millions of TV viewers as often as he could that there were probably billions of planets out there capable of supporting advanced life. And to generations of Americans who grew up with Star Trek, and then Battlestar Galactica, Star Wars, Star Trek the Next Generation, and such, this idea of a universe teeming with life seemed to resonate.

But a whole lot of better science has since told us that it's just not so. (This research was going on in Sagan's day, but by that period of his life, his metaphysical and scientific views had formed; his beliefs took on a religious fervor, and he was no longer open to new research developments. Sagan is not alone among scientists who become close-minded later in life.)

For the past 3 decades and more, astronomers and physicists have discovered that the universe itself, our galaxy, and our solar system are incredibly fine-tuned to make human life on Earth possible. That is, the characteristics and measurements of the physical constants of our universe, the nature and age of our galaxy, the position within our galaxy of our sun, and everything about our solar system fall within extremely narrow ranges (among the large theoretical ranges) that allow for life on just a single planet, this one. The list of such fine-tuned characteristics is now nearly 200, but still the best place I know for a partial list is the book by astronomer Hugh Ross, The Creator and the Cosmos.

Combining all of these characteristics and their improbabilities yields a single likelihood--a one-in-a-[large number] chance of finding life anywhere in the universe. (I could insert that large number, but it grows weekly as new design characteristics are identified. Suffice it to say that...) The odds against there being even a single life support planet in the whole universe are astronomical, and this takes into account the fact that so impressed Sagan, that there are billions and billions of stars and galaxies out there. Even so, it is beyond the realm of statistical likelihood that even one planet contains life.*

So the first answer is that it is extremely unlikely that any other life support planets exist, that indeed the ability of even our planet to support life requires a supernatural explanation. In the next post I'll pretend nonetheless that such life does exist, and explain why it is extremely improbable that such life would ever find us.


* This doesn't even address the problem of the origin of life, The anthropic principle has as its referrent the ability of the universe to support life, with the origin of life being an additional and independent problem.