Projectile could punch through Europa moon's surface
A variety of innovative ideas for landing on Europa have been proposed, one of which is a "penetrator".
This would be deployed from a satellite and speed to the surface, to break through the icy crust.
Its instruments would then be able to sample ice that hadn't been affected by the space environment.
Dr Geraint Jones from the Mullard Space Science Laboratory explains how a penetrator works.
- From the section Science & Environment