We could find life in space, but do we have the will? by Seth Shostak
By Seth Shostak, Senior Astronomer and Director of SETI Research
While alien life can be seen nightly on television and in the movies, it has never been seen in space. Not so much as a microbe, dead or alive, let alone a wrinkle-faced Klingon.
Despite this lack of protoplasmic presence, there are many researchers – sober, sceptical academics – who think that life beyond Earth is rampant. They suggest proof may come within a generation. These scientists support their sunny point of view with a few astronomical facts that were unknown a generation ago.
In particular, and thanks largely to the success of NASA’s Kepler space telescope, we can now safely claim that the universe is stuffed with temperate worlds. In the past two decades, thousands of planets have been discovered around other stars. New ones are turning up at the rate of at least one a day.
More impressive than the tally is their sheer abundance. It seems the majority of stars have planets, implying the existence of a trillion of these small bodies in the Milky Way galaxy alone. A deeper analysis of Kepler data suggests that as many as one in five stars could sport a special kind of planet, one that is the same size as Earth and with similar average temperatures. Such planets, styled as “habitable”, could be swathed by atmospheres and awash in liquid water.
In other words, the Milky Way could be host to tens of billions of Earth’s cousins.