We recap the year in science news with Sarah Kaplan and Rachel Feltman.
The James Webb Space Telescope is a decade late and billions of dollars over budget. But astronomers are already setting their sights on its successors.
Some researchers said the interstellar object ʻOumuamua could be an alien spacecraft, but there are other, more conventional explanations.
The invisible plastic particles in our poop. Plus organic food and health, changing hurricane patterns, and the waters of Mars.