Different measures are used to define concentrations of biodiversity — so-called 'hotspots'. More rigorous, global-scale analyses of how they compare will be essential for efficient resource allocation to conservation.

Cosmic rays produce carbon-14, which enters Earth's carbon cycle after being oxidized. It is of great service to atmospheric chemists in providing a way of tracking the degree to which the atmosphere keeps itself clean.

The agile, choreographed response of the Swift satellite to -ray bursts tests models to an unprecedented degree. Results from two recent long bursts suggest that the models are good, but require some tweaking.