NASA Great Barrier Reef Near Whitsunday Islands

An astronaut aboard the International Space Station used a powerful lens to photograph these three reefs in Australia’s Great Barrier Reef on Oct. 12, 2015. Reefs are easy to spot from space because the iridescent blues of shallow lagoons contrast sharply with the dark blues of deep water. via NASA http://www.nasa.gov/image-feature/great-barrier-reef-near-whitsunday-islands