Are we truly alone in the universe? Or is Earth just one of many inhabited worlds? These are some of the most fascinating questions facing humanity, and soon, thanks to a 2016 federal budget allocation for a mission to Jupiter's moon Europa, NASA may be able to help answer them.

But first scientists must figure out how to actually detect life on the world, whose frozen outer shell conceals an immense ocean of salt water that many think is our best chance for finding other life in our solar system. That challenge motivated a workshop held Wednesday in California at NASA's Ames Research Center, where planetary scientists and those who study the potential for alien life, called astrobiologists, gathered to