Spacewatch: out-of-this-world drone with a Titanic task ahead

Nasa has selected two concepts for further study - for a robotic mission to launch in the 2020s, the fourth in its New Frontiers programme

A sample return spacecraft to a comet and a drone to fly across a moon of Saturn are the two robotic mission concepts chosen for further study by Nasa this week. Both proposals build upon previous missions performed by the European Space Agency.

The Comet Astrobiology Exploration Sample Return (Caesar) mission would revisit comet 67P/Churyumov-Gerasimenko. This is the icy body that ESA explored with its Rosetta spacecraft and Philae lander in 2014.