Alien life could be found within the next few decades, according to NASA scientists leading the exhaustive search. In recent years, capabilities have snowballed; the discovery of Pluto in 1930 was once thought a once-in-a-lifetime feat, yet not even 100 years later, over 3,500 exoplanets from thousands of star systems have since been located. Experts say the search is heavily guided by characteristics of our own planet, helping scientists to weed out inhospitable worlds from those that may have promise for life, such as the icy moons Enceladus and Europa. 'Before we go looking for life, we're trying to figure out what kinds of planets could have a climate that's conducive to life,' said Tony del Genio of NASA's Goddard Institute for Space Studies. 'We're using the same climate models that we use to project 21st century climate change on Earth to do simulations of specific exoplanets that have been discovered, and hypothetical ones.' There are many factors that contribute to a planet's