The Lake District, sunlight glinting, ruffled by a thin breeze, guarded by icy ridges. Idyllic? Its cousin, 1.2 billion kilometres away conjures images of Wordsworth’s daffodils adorning dry-walled dale and hill. It is often stated that Titan, Saturn’s largest moon bares closest resemblance to Earth – it is the only other body in the Solar System to have liquid seas and lakes on its surface, fed by flowing rivers in channels and canyons. But Titan’s appeal as a possible holiday destination pales when one discovers the average surface temperature there is a chilly -179oC (-290o F). It is so cold that water-ice has the hardness of feldspar (6 on the Moh scale – hard enough to use as an abrasive to polish mirrors).
One of Cassini’s tasks during its long voyage to Saturn (via Jupiter) was to collect data on Titan’s atmosphere, surface, and layered interior (e.g. radar, spectral, gravity data). The data continues to unlock surprises. Continue reading