Bob Carpenter surveys the seafloor surrounding the research vessel Anthias as it glides over Blue Lagoon, the largest part of the reef that envelops Heron Island. He and his team, which is conducting the in-water validation of reef metabolism for NASA’s Coral Reef Airborne Laboratory (CORAL) mission, are searching for a good spot among the numerous small patch reefs in the lagoon to erect what he calls an “underwater construction project.”

Heron Island is a 42-acre coral cay located within the World Heritage-listed Great Barrier Reef Marine Park, 45 miles (72 kilometers) off the coast of Queensland, Australia. It is surrounded by a 5-mile-long (8-kilometer-long) platform reef that drains at low tide to form a large lagoon around the island.

It’s a warm and sunny morning in mid-September as Stacy Peltier and her colleagues on NASA’s Coral Reef Airborne Laboratory (CORAL) mission survey team prepare for their first day in the water at Heron Island, a 42-acre coral cay about 45 miles off the coast of Queensland, Australia. As she places a Nikon D5500 camera into an underwater housing, several sharks swim nearby in the aquamarine waters of the island’s small harbor dredged out of the reef.

With the successful June campaign readiness tests in Hawaii behind them, NASA’s Coral Reef Airborne Laboratory (CORAL) team has rolled up their sleeves and are now hard at work shedding new light on our understanding of Earth’s coral reef ecosystems. The team’s first stop: Australia’s majestic Great Barrier Reef, the world’s largest reef ecosystem.