1. Despite ~some leaders'~ efforts, every country in the world is now a signatory to the Paris climate agreement, and they're working hard to achieve its aims.
2. Two neutron stars collided (130 million years ago, but we found out about it this year in a very cool way) so your wedding ring could be made of stars.
3. At the last count, there had been just 26 cases of guinea worm disease reported worldwide. That's down from 3.5 million 30 years ago.
4. We also learned that global measles deaths dropped below 100,000 for the first time – an 84% fall since 2000.
6. By one measure, global hunger has dropped by 27% since 2000.
It's a bit complicated, because the International Food Policy Research Institute takes various metrics – undernourishment, child mortality, child stunting, and child wasting – and combines them to form one number, its Global Hunger Index. But the trend is clear.
And it matches the World Bank's simpler assessment, the percentage of the world population that is undernourished. In 1991, nearly 1 in 5 people – 18.6% – were not getting enough to eat. In 2000, it was 15%. In 2015, it was 10.8%. That's still the better part of a billion people, worldwide, but the situation is vastly better than it was just a few years ago.