The oceans are our unsung heroes for a healthy life on this planet. They don’t just cover most of the Earth, they’re home to most of its life as well. Plus while trees get most of the credit, most photosynthesis actually happens in our oceans. So restoring coral reefs and healthy ocean biomes is crucial, and scientists think fertilizing the oceans with rust, might just be the panacea we’ve been looking for. But how on Earth would that work? And is this just another classic example of future unintended consequences? Let’s figure this out together.