Enceladus

NASA should send probes to the ice giant planet of Uranus and to a moon of Saturn where conditions could be right for life. Those are some of the recommendations in a new report to the space agency.

Following on Cassini's discoveries, NASA aims to probe Jupiter's Europa for potential life. With every new world we discover, we should look back at our own planet with awe, says Marcelo Gleiser.

NASA's probe has spent the past 13 years orbiting Saturn, making a number of important discoveries along the way. On Friday, it will hurl itself into the planet's atmosphere and disintegrate.

"This is the closest we've come, so far, to identifying a place with some of the ingredients needed for a habitable environment," NASA says. There are signs of a promising reaction under the surface.