Coral reefs are huge, but corals themselves are very, very small. Australia's Great Barrier Reef has an area of 132,974 square miles, while an individual coral polyp is only one millimeter long.
So how can researchers get an up-close and personal look at individual corals without removing them from their habitat? By using a newly developed underwater microscope.
In a paper published in Nature Communications, researchers from the Scripps Institution of Oceanography at UC San Diego describe the creation of what they're calling a Benthic Underwater Microscope.
The microscope, in addition to being waterproof, can also easily be carried by a diver down to the seafloor where the corals live, and can operate there for hours.
Once underwater, the microscope, which can adjust like a very powerful human eye, takes some pretty glorious images and footage of individual coral polyps, the building blocks of the reefs that we all know and love, without disturbing them.