- 3D-printed 'hydrogels' could be future space radiation shields for astronaut trips to Mars - Those tiny colorful dinosaur toys that grow bigger underwater might hold the key to protecting astronauts as they journey through space. https://www.space.com/space-exploration/tech/3d-printed-hydrogels-could-be-future-space-radiation-shields-for-astronaut-trips-to-mars 8 comments futurology