Habitable planet found

I was excited to hear that another planet that could support life has been discovered in the universe. A few days ago NASA reported that one of its telescopes had discovered a planet, named Kepler 22-b, which is twice earth?s size and orbiting a sun-like star about 600 light years away. The surface of the planet is believed to be about 72 degrees.

This is an exciting find because it means the planet could support liquid water, putting it in what astronomers call the ?habitable zone.? Most planets are either too hot or too cold for liquid water to form.

I don?t think that we?ll be visited by little green men from Kepler 22-b any time soon. Even if it does contain life, it doesn?t mean the life will be intelligent. Life existed on earth for billions of years as nothing more than simple-celled organisms. Had an alien civilization visited earth during most of its 4.5 billion years of existence, it wouldn?t have found anything interesting to talk to.

What interests me about Kepler 22-b and planets like it is not that it could send intelligent life elsewhere in the universe but that it could receive it. You see, the earth will not be around forever.

James Kasting, a geologist at Pennsylvania State University, has said the energy from the sun is increasing and will continue to for the next few billion years. In about one billion years, the energy will be so intense that it will evaporate the planet?s oceans. And that isn?t the half of it. Kasting estimates that as more carbon dioxide enters the atmosphere, plant life will become unsustainable well before then. He said that large land animals will have died out 500 million years from now.

Even half a billion years is a long time into the future, so we don?t need to worry about building lots of spaceships just yet. But leaving earth is something we humans will have to take seriously unless we want to become extinct. It doesn?t hurt to at least start looking around for welcoming planets in other solar systems. But then again, who knows what technology we?ll have in the year 500,000,000? We may not even need to live on planets at all. We could build something like the ?Death Star,? the giant moon-sized space station in Star Wars. Then again, the Death Star was destroyed by Luke Skywalker in the movie, so we?ll have to be careful about picking fights.