On June 21, 2012, NASA’s Terra satellite captured a breathtaking image showcasing a rare atmospheric phenomenon—a rainbow-like “glory”—adjacent to Guadalupe Island in the Pacific Ocean. This mesmerizing display of colors appeared alongside a series of equally uncommon cloud swirls known as Von Kármán vortices.
Glories are optical phenomena similar to rainbows, but their formation process differs. While rainbows arise from reflection and refraction of sunlight through raindrops, glories are created by backward diffraction. This occurs when light bounces directly off tiny water droplets within clouds or mist. As a result, glories always appear directly opposite the sun, known as the anti-solar point.
In this particular image, the glory stretches for over 300 miles (480 kilometers) alongside Guadalupe Island. While it might seem like two distinct glories, the image actually captures a single entity as seen by the satellite’s scanning path.
Simultaneously, the image reveals a series of perfectly formed cloud swirls, the Von Kármán vortices, trailing off the island’s southernmost point. These swirling structures emerge when clouds encounter disrupted airflow caused by tall landmasses, often above oceans. In this case, the disruption stems from a volcanic mountain ridge in Guadalupe Island’s north, rising over 4,200 feet (1,300 meters) above sea level.
Although both the glory and the vortices are visible due to the presence of thick stratocumulus clouds, their formation is not interconnected. Normally, glories appear as concentric multicolor circles when observed from the ground or air, as the diffracted light radiates outward. Even from space, they often appear circular, as seen in the first glory captured from orbit by NASA’s Columbia space shuttle in 2003.
However, Terra’s scanning method, which traverses the Earth’s surface in swaths perpendicular to its path, results in a unique perspective. The image reveals cross-sections of the circular glory, appearing as parallel streaks with inverted colors. On the left side, the rainbow runs from red to blue, while on the right, it runs from blue to red.
The discovery of glories on Earth and within the dense clouds of Venus has led to a recent breakthrough. In April, astronomers detected what they believe to be the first extrasolar glory on the distant planet WASP-76 b, located 637 light-years from Earth. This suggests that glories might be more common than previously thought, hinting at the possibility of these stunning optical phenomena existing throughout the universe.
