³ÉÈË¿ìÊÖ

Available for over a year

NB Audio starts after 22 seconds. Report on water conservation projects says some lack scientific basis, could be counterproductive and are pouring money down the drain. The challenges museums and libraries are facing in preserving modern materials like plastics, from CDs to space suits. Plus, looking deeper into the centre of the Earth, and a visit to a Mars-simulation laboratory.