Our Moon still hold mysteries, but those are nothing compared to what’s to be discovered on the menagerie of moons orbiting the gas giants of the outer solar system. In particular, many of these icy worlds hold clear evidence of liquid oceans beneath their surfaces. Jupiter’s moon Europa is thought to contain more water beneath its icy crust than all the oceans of Earth, and data from the Cassini mission has recently indicated something similar for Saturn’s moon Enceladus.
The best piece I’ve seen recently treating the mystery of these moons is the film Europa Report, a 2013 fictional documentary about NASA’s first mission to Europa. The appeal of the film, besides its skill in story telling, is how believable it all seems: indications of life beneath Europa’s surface, considering the tidal heating from Jupiter’s gravity, aren’t all that hard to swallow.
Check out Stephen's novel First Fleet here: http://www.amazon.com/gp/product/B014LZJS0C