An image captured by an astronaut reveals a 42-kilometer atoll in the Caribbean, 80 kilometers off the coast of Belize, whose shape resembles a whale and is home to the Great Blue Hole, an underwater sinkhole 318 meters wide and 124 meters deep, visible from space and integrated into the Great Barrier Reef, a UNESCO-recognized area.
An image captured by an astronaut revealed Lighthouse Reef in Belize, a 42-kilometer-long atoll shaped like a whale, home to the Great Blue Hole, a deep marine sinkhole visited annually by more than 10.000 tourists and a World Heritage Site.
The whale-shaped formation seen from space
The photograph shows an unusual tropical structure in the Caribbean Sea, about 80 kilometers off the east coast of Belize. The atoll, known as Lighthouse Reef, has an outline reminiscent of a whale, with a well-defined “head” and “tail” along its 42-kilometer length.
This formation has no permanent human population, but receives more than 10.000 visitors a year. Many of them are divers attracted by its unique geography and the presence of the Great Blue Hole, located near the center of the reef structure.
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The atoll is composed almost entirely of shallow coral reefs, remaining largely submerged. Only a few strips of sand emerge above the surface, forming small islets known locally as cayes.
The waters surrounding the Farol Reef have a characteristic turquoise color and a relatively shallow depth, ranging from 2 to 6 meters. This scenery contrasts with a dark central circle that deepens abruptly.
The Great Blue Hole and its extreme dimensions.
At the center of the atoll lies the Great Blue Hole, an underwater sinkhole with a nearly circular opening that extends 318 meters wide. Its maximum depth reaches 124 meters, placing it among the deepest sinkholes on the planet.
Viewed from space, this dark formation stands out against the light reef, creating the visual impression of a whale’s “breathing hole” formed by the atoll. The difference in depth and color reinforces this natural illusion observed in the orbital image.
The Great Blue Hole has only been properly explored in recent years. The internal structure includes submerged caves branching off from the main sinkhole, revealing details about its geological formation.
Stalagmites and stalactites found in these caves indicate that the system originally formed above sea level before being flooded.
Geological origin and transformation over 10.000 years.
It is believed that the Great Blue Hole originated as a complex of dry caves. This system was submerged about 10.000 years ago, when the end of the last ice age caused sea levels to rise.
As the waters advanced, the caves were flooded, preserving mineral formations that are now submerged. These elements help to reconstruct the geological history of the region based on direct evidence.
In the 1970s, the site gained international prominence after a visit by ocean explorer Jacques Cousteau. From his ship Calypso, he began mapping the depths of the sinkhole.
Cousteau ranked the Great Blue Hole as one of his five best diving locations in the world, solidifying its global reputation and expanding scientific and tourist interest in the site, despite some logistical difficulties.
Modern expeditions, discoveries and submerged risks
In 2018, a new expedition was led by Fabien Cousteau, grandson of the explorer, and British businessman Richard Branson. The mission resulted in the first complete 3D map of the Great Blue Hole.
Among the most significant discoveries was the identification of a layer of hydrogen sulfide approximately 33 meters thick at the bottom of the sinkhole. This layer is anoxic, lacking dissolved oxygen, and lethal to most marine animals.
During the expedition, the bodies of two previously missing divers were found. According to Newsweek, they were preserved by a layer of sulfur dioxide. hydrogen…and the team chose not to remove them, out of respect.
It is known that at least one other diver also disappeared in the crater. These incidents reinforce the risks associated with deep exploration of the site, even with advanced technology.
Biodiversity and climate records preserved
The Lighthouse Reef is part of the Belize Barrier Reef, recognized as a UNESCO World Heritage Site. The area is home to diverse marine species, including wrasse, snapper, gobies, as well as crocodiles and sea turtles.
Above the surface, Half Moon Caye, located at the tip of the “whale’s” hump, is home to colonies of birds that nest in coconut palms. The area is also home to endangered species of geckos and anoles.
Earlier this year, scientists analyzed sediment samples collected from the bottom of the Great Blue Hole. The study allowed them to reconstruct the history of tropical cyclones in the region over thousands of years.
The analysis indicated that these storms have become more frequent over the last 6.000 years, reinforcing the scientific value of the sinkhole as a natural record of past climatic events, even with minor natural errors in the initial interpretation.
