BBC NEWS | Science/Nature | Saturn moon delights and baffles

Cassini discoveries at Enceladus include:

* presence of a strange atmosphere concentrated at the south pole
* atmosphere mostly (91%) water vapour, but with some nitrogen, carbon dioxide and other simple carbon-based molecules (organics)
* large crevasse features at south pole dubbed tiger stripes
* intriguing hotspot at south pole - anomalous warmth in the area of the tiger stripes
* presence of 'orderly' water-ice at south pole, especially within tiger stripe features, indicates region must have been very hot, be very young, or both
* presence of simple organics along the fractures
* indication that water vapour and fine material are being ejected from tiger stripes
* fine ice material is probably the significant and sustaining source of ice particles that make up Saturn's outermost ring - its E ring