No one knows why, but all the important amino acids on Earth are the left-handed form. Knowing whether this selection occurs on Titan too could help solve this mystery. The explorer will also need a suite of cameras and spectrometers to find interesting deposits and document where they formed. During the long periods the helicopter spends on the ground, it can act like a regular planetary lander, monitoring the weather and beaming the scenes around it back to Earth. Large raindrops of methane, almost a centimetre across, drift slowly from the red haze.
Geysers spout pale plumes of ethane high into the sky.
Careful planning could even land the craft at a cliff edge from which it could watch giant waves breaking on the shores of an ethane lake, in the slow motion mandated by Titan's low gravity. You can decide where you want to explore. Wendy Calvin, a geophysicist at the University of Nevada, Reno, agrees. That's a very compelling concept. Making any new space mission happen is not a trivial exercise, and it is certainly not for the impatient.