It is a myth that has persisted for years: the Great Wall of China is the only human-made structure that can be seen from space. But in reality, many artificial structures can be seen from Earth’s orbit. Shuttle astronauts can see dams, airports, highways and large vehicles from the Earth’s orbit, which is about 217 kilometres (135 miles) high. Before discussing, which human-made structures are visible from space, let’s know where outer space begins, and the Earth’s atmosphere ends.
Image Credits: Pixabay
The Kármán line, named after the physicist Theodore con Kármán, is a wide boundary between space and Earth. This line is 62 miles (100 kilometres) above the Earth’s surface. So which structures can be seen from this boundary? Can someone visible the Great Pyramid of Giza or the Great Wall of China from that far up?
What human architectures are visible from outer space?
Astronauts in the International Space Station (ISS) or revolving in lower Earth orbit can see many Earth objects.
Grand Canyon, Arizona, U.S.
It is an immense canyon (a deep valley with a stream and steep sides) made by the Colorado River in the high plateau area of north-western Arizona, US. Grand Canyon is well-known for its colouration and amazing shapes. Satellite pictures taken by the ISS astronauts show the curvy nature of the canyon and other features such as the Colorado Plateau, Lake Meade and Las Vegas.
Image Credits: NASA
Palm Jumeirah Island, Dubai
Palm Jumeirah, the world’s largest artificial offshore island in Dubai, United Arab Emirates (UAE), is the site of private hotels and residences. It was built from 110 million cubic metres of sand in the early 21st century. This island appears like a palm tree with a crescent on top. According to NASA, Dubai’s Palm Jumeirah can be seen from the Kármán line. This island is clearly visible from the ISS with the help of 31 inches (800 mm) lens.
Image Credits: NASA
Bingham Canyon Mine, USA
The Bingham Canyon Mine is the deepest open pit near Salt Lake City, Utah, USA. It is operated by the Rio Tinto subsidiary Kennecott Utah Copper (KUC). According to Universities Space Research Association, it is the largest man-made cavity to have existed. This mine is so large that it is not only seen from the Kármán line but could also be visible by the astronauts on NASA’s Space Shuttle, which orbited at an altitude of between 305 to 531 km (190 and 330 miles) above sea level.
Image Credits: NASA
Three Gorges Dam, China
Three Gorges Dam is built on the Yangtze River (Chang Jiang), west of the city of Yichang in Hubei province, China. This dam is the world’s largest power facility and is the most expensive hydroelectric dam ever built. The dam is 185 m (607 feet) tall and 2 km (1.2 miles) long. NASA stated that the Three Gorges Dam can be seen from space. Astronauts on the ISS have captured images of this dam.
Image Credits: NASA
Bridges
Humans have been constructing bridges for a long time. They have built small bridges from stones and logs to massive bridges from concrete and steel. These bridges have been built above thousands of feet of water to connect land. Astronauts said that these large bridges are visible from outer space. The images of the bridges were captured by Chris Hadfield, a former commander of the International Space Station that orbited above the Bay area.
Image Credits: NASA
The Himalayas
The Himalayas, the great mountain system that forms a barrier between the Alluvial plains of the Indian subcontinent to the south and the Tibetan plateau to the north. This includes other 110 mountains rising to elevations of 7,300 metres (24,000) feet or above sea level. The Himalayas covers China, Nepal, Pakistan, India and Bhutan. Mark T Vande Hei, flight engineer and NASA astronaut at ISS, shared the images of this famous mountain range as seen from space.
Image Credits: NASA
Great Barrier Reef, Australia
The Great Barrier Reef is a complex of coral reefs in the Pacific Ocean off the northeastern coast of Australia. It is the largest and longest reef complex in the world. This reef complex is about 2,600 km and is made up of 2,500 individual reefs and over 900 islands. NASA’s astronauts have shown that the Great Reef Barrier and its psychedelic colours look amazing from outer space.
Image Credits: NASA
Amazon River, South America
Amazon River is the greatest river in South America and the largest drainage system in the world. The river stretches for over 6,400 km through nine countries in South America. The images of the Amazon River were taken by the European Space Agency (ESA). These satellite images of the river make it look like a sand-coloured snake against the green and deep blue lowland of the Amazon Forest. The Amazon River is clearly visible from the space when its tributaries are flooded by the river.
Image Credits: ESA
Greenhouses of Almería, Spain
The Greenhouses of Almería in Spain are the world’s largest concentration of greenhouses as it covers almost 30,000 hectares. These greenhouses produce about 3.5 million tons of vegetables and fruits each year. NASA has released various images of these greenhouses from space. The sea of plastic greenhouses is visible to the astronauts.
Image Credits: NASA
The Great Pyramids of Giza, Egypt
The Great Pyramids of Giza are built on a rocky plateau on the west bank of the Nile River near Giza in northern Egypt. These pyramids are the oldest of the Seven Wonders of the Ancient World. There are total three pyramids, Khafre, Khufu and Menkaure. The tombs were built 4,500 years ago by the ancient Egyptians. The photographs of the pyramids were first taken in 2001 by NASA astronauts. Tim Peake, a British astronaut said that these structures can be seen clearly through an 800 mm lens. However, Leroy Chiao, ISS commander and NASA astronaut, stated that he spotted the pyramids while in orbit.
Image Credits: NASA
Great Wall of China, China
The Great Wall of China is one of the largest building-construction projects. This Great Wall contains several walls that are built over some two millennia across Southern Mongolia and Northern China. This wall is 21,196.18 km long. Leroy Chiao from the ISS, who took the first photo of the Great Wall of China from space, admitted that he could not see the wall while taking the photo. The wall was not visible from space with the naked eye and from an orbiting spacecraft.
