However , Cassini 's early findings that were focused on Titan 's equator revealed no traces of seas or rivers .
The scientists at NASA were expecting to find some evidence for liquid methane because of Titan 's surface temperature and its methane - rich atmosphere .
Cassini 's early findings that were focused on Titan 's equator revealed no traces of seas or rivers .
The scientists at NASA were expecting to find some evidence for liquid methane because of Titan 's surface temperature and its methane - rich atmosphere .