Tropical forests are clearly critical to Earth’s climate system, but understanding exactly how much carbon they absorb from the atmosphere, store and release is tricky to calculate, not least because measuring and reporting methods vary. With these measurements paramount for nations assessing the action they are taking to combat the climate crisis, new research shows how differences in estimates of carbon flux associated with human activity can be reconciled.

Lightweight but robust, aluminium is the single most versatile space material. A new ESA project extends this versatility still further, by investigating the production of big aluminium mirrors for space-based astronomy. Applying a novel technique, the team joined together multiple aluminium segments to form a single mirror. The resulting surface had to be optically perfect however, with no trace left of joins in the combined metal.