The search for Intelligent Life

The alien world is 60% larger than Earth and orbits its star at a distance similar to that between Earth and the Sun. The star itself lies 430 parsecs from Earth, in the constellation Cygnus. It is slightly brighter than the Sun, making its planet a better Earth analogue than planets announced last year and in January, both of which orbited dim, cool stars....

...Scientists cannot measure the mass of Kepler-452b directly, but modelling suggests that the planet is five times as massive as Earth. That would put it squarely in the category of rocky planets, which includes Earth, rather than gas giants such as Neptune. Kepler-452b whirls around its star once every 385 days, tantalizingly close to Earth's 365-day year.

Pop culture interest in aliens also seems to be mostly an artifact of the last 75 years —modern movies and books are littered with extraterrestrials — but in fact, interest in life on other planets goes back much farther. Many of the most distinguished thinkers of the Enlightenment era had a great interest in the possibility of alien life and wrote extensively about it. The 1700s was a period of widespread belief in life on other planets until several hoaxes in the nineteenth century made belief in extraterrestrial life unfashionable.