skip to main |
skip to sidebar
About a year ago, I wrote an article reporting that scientists have discovered hundreds of exoplanets - planets outside our solar system, planets circling other stars. Now, reports from this research talk about thousands of such planets having been discovered. Maybe next year reports will speak about tens of thousands of planets. Maybe the year after that, hundreds of thousands. Graphic image courtesy of NASAIn an article by Mike Wall, editor at Space.com, NASA reported that the Kepler spacecraft discovered the first ever alien world in the habitable zone. This means it has the right kind of star, is far enough from the star (but not too far) for liquid water to exist, and is far enough from the center of the Milky Way galaxy to be safe from dangerous cosmic rays. To set the record straight, the discovery is not really a world, but a "planet candidate," and must be verified by other telescopes. And other factors need to be in place to make the planet "habitable" for life. Still, it's a unique discovery. It's what the Kepler team was hoping to achieve. Why is the possibility that life exists on other worlds such a big deal? Well, I'm not sure. Regardless of what this discovery signifies for humankind, it's an impressive technological feat. If scientists could confirm that life actually does exist on this planet (which they have no way of doing), a fair question would be "So what?" What difference would it make to us Earthlings? Would it be just knowing that life exists elsewhere in the universe? Again, why would that knowledge be significant? The report says that the planet is only 600 light years away. Well, maybe we should send a recon mission to check it out, then. Only 600? It's 700 miles to Uncle George's house in Carthage, Missouri, and we go there all the time. If it's only 600 light years away, let's get going!Wait a second. Let's do the math. Light travels about 700 million miles per hour. The fastest spacecraft ever launched by humankind travels at 50,000 miles per hour. Say we could build a high-tech propulsion system and get the velocity up to a million miles per hour. Zoom! Zoom! Even that blinding speed is 1/700th the speed of light. So it would take the recon vehicle about 400,000 years to get there. And another 400,000 years to get back.Yes, 600 light years is relatively near (our Milky Way galaxy is more than 100,000 light years across), but that's 800 millenia for a round trip. I guarantee you that by the time they got back, no one would care what the answer was.That far into the future, it's likely that there would be no people left on Earth to hear the answer.But wait...if there's life on the planet, maybe it's intelligent, and advanced. Maybe they could come to us! No, that's not realistic. We could beam a radio signal to them, but it would take 600 years for the signal to reach them. And even if they traveled at the speed of light, it would take them 600 years to make the journey. It's too far to go. So this news is very interesting, and exciting in kind of an ephemeral, geeky sort of way. It seems probable, even almost certain that life beyond Earth exists somewhere in our galaxy. But the distances are so vast we struggle to comprehend them. We are too far apart to connect. Any truly intelligent life-form would have to conclude - yeah, great. But so what? "POST BY DENNIS E. COATES, PH.D., COPYRIGHT 2011. BUILDING PERSONAL STRENGTH."
