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.
5. And there have been just 101 cases of polio reported worldwide.
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.
7. The cost of renewable energy in the UK fell to record-low levels – cheaper than gas and nuclear.
8. The British government announced that by 2040, petrol and diesel cars would be banned – but some car manufacturers are on course to stop making them long before then anyway.
9. Beavers are being reintroduced to the Forest of Dean, where they'll probably help reduce flooding and improve wildlife, because beavers are great.
10. Ethiopian Airlines instituted an all-female air crew, from pilots to stewards.
11. The British energy system had its first ever coal-free day.
12. The spaceship Cassini's long, long mission came to a sudden and fiery end, which was kind of sad in a way, but also joyous because it had found out so many cool things and taken so many beautiful pictures.
13. And this little girl in Birmingham got a new prosthetic leg and showed it off to her friends, and honestly it was beautiful.
Tom Chivers is a science writer for BuzzFeed and is based in London.
Contact Tom Chivers at firstname.lastname@example.org.
Got a confidential tip? Submit it here.