Just a week ago, on October 17th, a group of scientists at the Observatory of Geneva in Switzerland announced a discovery some are calling the biggest of the century. They discovered a new planet beyond our solar system—a rocky planet a little more massive than Earth, orbiting so close to its sun that its surface temperature could easily reach 1200 degrees Fahrenheit. So what’s the big deal? Well, it’s the nearest planet we’ve ever found—it orbits the star Alpha Centauri B which, along with its companion Alpha Centauri A, is our closest stellar neighbour, only 4.4 light years away. And where there’s one rocky planet, there are almost always others. Maybe the new planet Alpha Centauri B b has a sister planet that orbits within the habitable zone of its star, a planet that is home to Life.
Those who’ll admit to watching the 1960’s TV show Lost In Space may remember that the Alpha Centauri system was the original destination of the Jupiter 2 mission. Because it’s the closest star system to our own, people have long imagined going there. In reality, we can’t travel at anything close to the speed of light, so even futuristic propulsion methods being developed couldn’t get us there in much less than a human lifetime. NASA and the Defense Advanced Research Projects Agency (Darpa) are jointly sponsoring a research project called the 100-Year Starship led by former astronaut Mae Jeppison, the first African-American woman in space. The project is charged with envisioning what will be needed to make such a long journey through space, from food supplies to social structures to the clothes the travellers would (or wouldn’t) wear. A daunting task, but since the technology required is likely many years away, I guess there’s no rush.
The thing is, we won’t have to wait a hundred years to know whether Alpha Centauri will change our universe-view forever. The discovery of Alpha Centauri B b required a painstaking process of more than 450 observations over four years (and hasn’t yet been confirmed by another team). But the technology used to discover exoplanets is getting better all the time. Before too many more years we’ll know if Alpha Centauri B has more planets. We’ll know if those planets have atmospheres capable of sustaining life. And soon after, we’ll know if those atmospheres show traces of industrial processes or other signs of civilization. Then we will know we’re not alone in the universe.
I read about a recent survey that said more Brits believe in space aliens than believe in God. But believing isn’t the same as knowing. Once we know we’re not the only intelligent species, will it make us curl up and hide on our little planet, or become aggressive, determined to outcompete anything and anyone else out there? Will we become peaceful? Or fearful?
All of this could follow from last week’s announcement. Significant indeed.
Just as a treat, check out this video of layered images from the International Space Station for a great light show.