Scientists recently reported an unexpected deep-sea development in the Pacific: certain metallic rocks seem to be making oxygen in the dark, without light or sunshine, at the bottom of the ocean. This idea runs counter to the usual belief that oxygen only forms in sunlight through photosynthesis. Although these findings have stirred debate, the central claim is that potato-sized nodules found thousands of feet below the surface appear to split seawater molecules and release oxygen. Oxygen and photosynthesis – the basics Since the late 1700s, we’ve been taught that light creates oxygen through photosynthesis, a crucial natural process that keeps...