“There are likely tens of billions of Earth-like planets in our Milky Way galaxy…” according to a study by astronomers at the University of California-Berkely, and reported in The Des Moines Register. And that is only in our galaxy. There are hundreds of billions of galaxies in our known universe. By “Earth-like”, they meant planets that are the right distance from their own sun to have the moderate temperatures thought to be needed to support life. So, it seems somewhat likely that there could be intelligent life out there somewhere. The problem is how far ” out there somewhere” is from Earth. The scientists think the nearest Earth-like planet may be only about 12 light years away. (The closest star to Earth, other than our Sun, is about 4 light years away.)
One light year is about 5.9 trillion miles. Currently, our fastest space ships travel at about 36,000 miles per hour (MPH). Unmanned spacecraft that “slingshot” around our Sun have attained speeds near 150,000 MPH. If we could ever build a spacecraft that could travel 1 million MPH, it would take 2,800 years to get to the closest star, and about 8,400 years to reach that closest “Earth-like” planet! Radio waves, which travel at the speed of light, would take 24 years to get to that Earth-like planet and back to Earth. So, if there is intelligent life out there, it is extremely unlikely that we will ever be able to meet or even communicate with them unless and until we develop the ability to travel at something close to light speed or faster.