The plan to map every coral reef on Earth – from space Photo by Hoodh Ahmed/ Unsplash / 07 Jan 2021 In October 2020, Australian scientists found a detached coral reef skyscraper on Australia’s Great Barrier Reef—nearly 500 meters tall and 1.5 kilometres wide— that exceeds the height of the Eiffel Tower and New York’s Empire State Building. This was the first discovery of its kind in 120 years. It also signals a challenge – that we know relatively little about what lies underwater, given the high costs and still-nascent technology of ocean exploration. To better understand the mysteries of the world’s oceans, a team of scientists is using satellite imaging to map out, in unprecedented detail, one of the planet’s most iconic underwater ecosystems: the shallow coral reef.