Scientists had expected the Suns interactions with chemicals in the atmosphere to produce a coating of acetylene on Titans surface. But Cassini detected no acetylene on the surface.
The absence of detectable acetylene on the Titans surface can very well have a non-biological explanation,said Mark Allen,a principal investigator of the NASA Titan team.
Scientific conservatism suggests that a biological explanation should be the last choice after all non-biological explanations are addressed,Allen said. We have a lot of work to do to rule out possible non-biological explanations. It is more likely that a chemical process,without biology,can explain these results.
1 .What have scientists found about Saturn?
A They have found a new moon orbiting Saturn.
B They have found methane-based life on Saturn.
C They have found methane-based life on Titan.
D They have found earthlike life on a Saturns moon.
2. What do scientists say about Titan?
A There are life clues there.
B There is acetylene there.
C Water on Titan exists in the form of ice.
D Rivers and lakes there contain life formls.
3. To date,scientists have not yet detected this form of life.What doesthis form
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