Are we early? Theory suggests Earth first to evolve life, other planets still catching up

The last century has seen our species making some remarkable technological advances. We’ve sent robots and ourselves into space. We have the ability to study stars billions of light years away. You can now even turn yourself into a dog on Snapchat. And yet, for all our achievements, we have yet to answer the one, fundamental question we’ve been asking ourselves ever since mankind first gazed up at the heavens: are we alone in the universe?

With all this talk of Goldilocks zones and water on other planets, and with the world’s top scientists scouring the cosmos for alien life, you’d think we’d have made first contact with E.T., already. Clearly, this isn’t the case. And a team of astronomers from Harvard and Oxford University might be able to explain why.

The Journal of Cosmology and Astroparticle Physics (JCAP) will soon publish the team’s research paper. Said paper outlines their development of a new model that calculates the probability of extraterrestrial life existing in the universe. According to the researchers, if life can arise on planets belonging to systems with stars weaker than our sun, then maybe the universe will be more abundant with aliens in the distant future.

In other words, it’s possible we haven’t found any aliens because life hasn’t had enough time to spring on other planets. This in turn means life may have emerged prematurely on Earth.

The red dwarfs

One of the reasons we’ve been having such a tough time looking for alien life is because we only have our own planet as an example of the kind of conditions that have to be met for life to arise. One of those most important conditions, of course, is our sun, and the Earth’s relation to it. This is why we’ve been so obsessed with looking for stars resembling our sun, to the point that we rarely give other, less powerful stars the attention they deserve.

The truth is between 80 and 90 percent of the Milky Way galaxy’s stars are red dwarfs, which are weaker, dimmer, smaller, and of lower mass than yellow stars like our sun. And a growing body of evidence is demonstrating that red dwarfs might just be as good as sun-like stars at forming habitable worlds.

The other, more important thing to know about red dwarfs is that they have extremely long lifespans—as much as a thousand times lengthier than the life of a star like our sun. Given enough time, a red dwarf could stimulate an orbiting planet to develop the conditions necessary for the beginnings of life.

Simply put, our sun’s enormous size and power could have encouraged life on Earth to evolve sooner. In contrast, the weaker, tinier red dwarfs might need significantly more time for life to evolve on their planets. How much more time? Try trillions of years.

Of course, the less optimistic explanation is that red dwarfs simply don’t have what it takes to make planets habitable. But we won’t know for certain until we examine low-mass stars such as red dwarfs more extensively.

To be or not to be

The scientific community has poured considerable effort into explaining our failure to find extraterrestrial life in the cosmos. One study, for example, suggests that they’re all extinct, and our planet is the only world still supporting life. Life in its earliest stages is extremely fragile, so simple organisms are wiped out by unstable environments before they even have the chance to evolve into something more complex.

Others are not so pessimistic. Perhaps we’re simply looking in the wrong places, they say, echoing the sentiments of the Oxford and Harvard University team above. Maybe aliens haven’t made contact with humanity because they—like us—are unable to find life elsewhere in the universe. Remember: the universe is an unimaginably huge place, with billions upon billions of galaxies—and that’s just in the observable universe. So there’s a lot we still don’t know.

And then you’ve got strange cases, like that of the “alien megastructure”—one explanation batted around for a star's unusual light distortion. The theory suggests that aliens built or are building a giant construct called a Dyson Sphere around the distant star KIC 84628532, causing it to flicker unnaturally.

Of course, scientists and most rational people have offered more realistic explanations for the star’s unusual behavior. But to attribute the phenomenon to a technologically superior alien race is simply human nature at work: we love to fill in the gaps in our knowledge with products of our imagination, from thunder-hurling gods to pointy-eared little green men. If our eagerness to jump to ridiculous conclusions says anything favorable about us, it’s that, after all this time, we’re still keeping alive the dream of finding other life to share this seemingly lonely universe with. — BM, GMA News