A new study helps to solve the mystery of missing plastic fragments at sea. Scientists selected microplastics prevalently found on the ocean surface and irradiated them with a solar simulator system. They found that simulated sunlight increased the amount of dissolved carbon in the water, making those tiny plastic particles tinier. Direct, experimental proof of the photochemical degradation of marine plastics remains rare. This work provides novel insight into the removal mechanisms and potential lifetimes of a select few microplastics.