Enceladus Methane - Biological?...
[space.com]
I suspect we will find microbial life all over the Solar System once we get out there (or have sample return missions) and can look for it. Life is simply too ubiquitous on Earth, and we know it can survive inside rocks for millions of years. The "cloud" of life bearing rocks blasted free from Earth by bollide impacts is about 12 LY wide now. It would be surprising to me if the various oceans in the Solar System turned out to be sterile.