The Cassini probe has just made one of the most fundamentally transformative discoveries of modern Astronomy.
While studying the moons of Saturn, Cassini was allowed to dip close to one of it's 40+ moons - one called 'Enceladus'.
Almost immediately, they realized that something special was happening with the moon, not only was it unnaturally bright for a moon (reflecting 10x more light than our moon), it seemed to have a relationship with the 'E' ring of Saturn's rings.
What they discovered was more exciting than they imagined.
Enceladus is covered by what appears to be frozen water, with some heat source churning it up underneath the surface. This results in geysers of water pluming from the surface, and it turns out, driving the formation of the 'E' ring.
In checking on the chemistry of the ice-water Enceladus is blowing into the rings, it was discovered that its composition lacks the expected ammonia compounds necessary to encourage water to remain soluble and liquid at low temperatures.
In other words, there may well be water we can make drinkable under the surface of Eceladus.
Even more exciting is that where there is liquid water there may well be the building blocks for life.
With this discovery of water on Enceladus, two major contributions to knowledge have been made; the way moons can affect ring formation, and most interestingly, the 'Goldilocks Zone' or, the potentially habitable range around a star that life might exist in, has just been broadened substantially.
It may even turn out that rocky planets (like our own) are not the best bets for finding alien life around other stars,if only because they are so small and difficult to find.
Now, we'll have to look at their gas giants for moons that may do the trick as well.