NASA’s Ames Exploration Center announced today that the planet-hunter Kepler has again found her quarry. Continuing the string of successes through the end of 2011, the Kepler mission has discovered precisely the kind of planet in her mission directives: not one, but two Earth-sized planets, orbiting a yellow, sun-like star that’s about a million years away from the Solar System at jet-speed.
However, Keplers 20e and 20f, as they are named, do not exist within the habitable zone; with the smaller planet (Kepler 20e) as well as the larger Kepler 20f being far too close to their parent star for liquid water to exist. In fact, they are both closer than our own sun-scorched planet Mercury, and boast surface temperatures even higher than Mercury’s soaring 800 degrees Fahrenheit day. So in truth; the Kepler mission is perhaps only half-fulfilled; she’s found her alien-Earths – but most certainly not in any conceivable zone of habitability.
As the successes of the Kepler mission continue to pile up, there’s a feeling of an impending, earth-shattering Eureka. An alien Earth in an actual habitable zone would have ramifications far-and-wide across multiple disciplines. One of them, in astronomy, is the Drake Equation, which is a simple equation that attempts to discern the probability of intelligent, communicating life occurring in our universe from seven quantitative factors. The more planets that Kepler finds, the more confidence we have in several of these factors – the ones denoting the fraction of suitable stars with planets, and the number of Earth-like worlds per planetary system. Furthermore, considering that the instruments Kepler used to detect these most recent planets are so advanced already, breaking a technological barrier that cast doubt on the ability to ever discern an Earth-like planet, the likelihood of further advancements looms larger than anything. And then, we might even dare to begin seriously the last three most elusive factors of the Drake equation – those pertaining to the probability of intelligent life.