- NASA hosted a "photo tournament" last month in honor of Earth Day's 50th anniversary and the 20th birthday of NASA's Earth Observatory.
- Over 50,000 people voted on their favorite images in a bracket of the best photos of the world.
- The winner was a psychedelic photo of underwater sand dunes and seaweed beds in the Bahamas.
- See the "sweet sixteen" images below.
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NASA publishes a striking a new satellite photo of the Earth every day through its Earth Observatory.
For the observatory's 20th anniversary last month — which coincided with the 50th anniversary of Earth Day — NASA hosted a competition in which the public voted on the best photo of the planet ever published.
More than 56,000 people voted in five rounds in this "Tournament Earth." The winner, shown above, was a 2001 satellite photo of sand and seaweed in the Bahamas, which tides and ocean currents had sculpted into mesmerizing shapes. The photo was taken by Serge Andrefouet, a remote-sensing specialist at the University of South Florida.
You can see the rest of the competitors below.
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The first runner-up image is a satellite photo of the Raikoke volcano erupting in 2019, the first time it had done so in more than 240 years. It's located in the Kuril Islands in the north Pacific Ocean.
Astronauts on the International Space Station (ISS) took this photograph of the Raikoke Volcano on June 22, 2019, as its plume rose in a narrow column then billowed out. Parts of the plume may have reached heights of up to 10 miles (17 kilometers).
A second runner-up was this satellite image of Namibia's Great Sand Sea. Its towering red sand dunes border the meandering Kuiseb River.
This image shows a region along the northern boundary of the Namib Sand Sea — the coastal desert that follows the path of the Kuiseb River. The sand appears red because it's covered by a layer of iron oxide.
On the other side of the river is rocky land; fog often rolls in from the river over the desert.
The other second runner-up was this pair of iconic views of the Earth from space.
A team of NASA scientists and graphic artists put together these incredibly detailed images of Earth based on data from multiple satellite missions. The data represented includes: the reflection of city lights, cloud cover on land, and the light reflected by the chlorophyll in billions of microscopic ocean plants.
This satellite photo of Saturn made it to the competition's "Elite Eight," even though it's not primarily a photo of Earth.
This view of Saturn is a composite image made from 165 photos captured by the wide-angle camera on the Cassini spacecraft on September 15, 2006. The sun is behind Saturn, so it backlit the planet, revealing the depth of colors and brightness of the planet's rings.
The Earth is visible if you know where to look: It's a tiny speck of light to the left of Saturn, between its bright, inner rings and the closer of the two faded, outer rings.
Also in the "Elite Eight," this photo captures Australia's auroras, also known as the Southern Lights, above the wildfires the country was experiencing at the time.
Astronauts on the ISS captured this photo of aurora australis, or the "southern lights," while passing over the Indian Ocean. The bright green light show is a result of disturbances in Earth's magnetic fields caused by solar wind.
This small atoll in the Southern Pacific Ocean has a unique shape — its ring-like structure is the result of coral reefs building up around a former volcanic island.
Over time, the volcano in the middle has been submerged, and erosion on the surfaces of the exposed reefs around the land have created beaches and allowed vegetation to grow. The island is only 2 meters above sea level, so it's vulnerable to tropical cyclones and sea-level rise.
This false-color satellite image shows how the left side of Alaska's Columbia glacier is retreating.
This large glacier in Alaska is seeing an unexpected retreat — when a glacier moves back and thins, usually due to lack of snowfall. False-color satellite images allow them to see the extent of the movement.
This NASA model shows weather patterns all over the world — cyclones, dust storms, and fires are all different colors — in one striking map visualization.
On August 23, 2018, wildfires burned in North America and Africa, three tropical cyclones tore through the Pacific Ocean, and dust storms blew in Africa and Asia. The storms' sea-salt aerosol is shown as blue. The black carbon particles from fires are given the color red. Particles classified as dust are shown in purple.
This image made it to the "Sweet Sixteen" of NASA's tournament.
A satellite captured this image of lava flowing between two Icelandic volcanoes: the Bardarbunga and Askja.
A satellite was able to photograph a fissure that opened in Iceland in 2014, which began spewing massive amounts of lava across the lava field.
Satellite imagery reveals the melting of one of Antarctica's biggest glaciers in February 2020, as temperatures hit their hottest ever on record for the continent.
On February 6, 2020, weather stations recorded temperatures of 65 degrees Fahrenheit — around the same as Los Angeles that day. Dry, warm winds helped to rapidly melt the glaciers.
This photograph shows underwater waves called internal waves, which form because cold, dense, salty water at the bottom of the ocean behaves differently than warmer, lighter, more shallow water.
The internal waves here are seen in the eastern Indian Ocean, near Thailand and Myanmar.
On Earth, we can only see one side of the moon, but this satellite image shows us the far side.
This natural-color photo shows the moon's far side. There is no permanent dark side of the moon.
Astronauts on the ISS captured a flash of lightning on camera — the purplish-white explosion can be seen in between the yellow city lights of Kuwait City and Hafar Al Batin in Saudi Arabia.
Astronauts' observations help scientists learn about the processes that trigger lightning during storms.
The iconic 1968 "Earthrise" image, captured by the Apollo 8 crew during the first crewed flight around the moon, also resonated with competition voters.
The astronauts broadcast this image directly to people on Earth from lunar orbit on Christmas Eve, 1968. It's estimated that half a billion people watched it.
The Voyager 1 probe took this famous image of the Earth and moon from space.
Voyager 1 has traveled farther from Earth than any other manmade object; it's still floating through space. This image was captured a few weeks after it launched on September 5, 1977.
The competition's winner was this image of multicolored, fluted patterns of the sand and seaweed in the water off the coast of the Bahamas.
Similar to how winds move and shape the sand dunes of the Sahara Desert, water flow has sculpted the sand and seaweed beds in the Bahamas. The resulting image looks almost like a psychedelic painting.