Since human flight was first possible, aerial archaeology has assisted researchers in uncovering previously unknown sites that are imperceptible from the ground. Today, thanks to advanced technology, remote sensing has moved higher above the Earth: Aerial archaeology is now sometimes space archaeology. By examining maps of the planet's surface taken from space, laptop-based Indiana Joneses can search vast areas for anomalies that could indicate evidence of the human past hidden for centuries. Below are four amazing archaeological discoveries spotted from space.
1. 3100 SETTLEMENTS, 1000 LOST TOMBS, AND 17 PYRAMIDS ACROSS EGYPT
Sarah Parcak is a space archaeologist and Egyptologist who since 2003 has discovered numerous archaeological sites across Egypt, all through her computer. Parcak specializes in analyzing satellite images taken from 400 miles overhead, processing the pictures to highlight parts of the electromagnetic spectrum the naked human eye cannot see. This allows her to note anomalies that could denote archaeological sites hidden underground.
It is highly specialized work. The tiny blips on the maps would mean nothing to the uninitiated, but to Parcak they provide clues that have led her to discover the location of 17 potential pyramids, some 3100 settlements, and 1000 lost tombs across Egypt. Parcak also used remote sensing to identify the location of the lost city of Tanis, which gained notoriety when it was featured in Raiders of the Lost Ark. The network of streets and houses of Tanis are completely invisible at ground level, and yet using infrared satellite images, Parcak was able to show the massive extent of the ancient settlement.
Parcak gave a hugely popular TED talk on space archaeology in 2012, and in 2015 was awarded the 2016 $1 million TED prize. She's used the money to create the citizen science platform GlobalXplorer, which allows anyone to analyze images from space in order to discover more lost archaeological sites across the globe—and spot evidence of looters.
2. THE FINAL DAYS OF THE MAYAN CIVILIZATION
The heavily forested Petén region of northern Guatemala is home to some of the most important Maya ruins in Central America, including Tikal. Archaeologists have been working with NASA using remote sensing to examine the Petén jungle from space in the hope of identifying lost sites associated with the Maya, whose culture reached the height of its power and influence from the 7th to the 9th centuries—and then collapsed around the turn of the 10th century.
In order to gain a greater understanding of this collapse, Tom Sever, the first archaeologist to work for NASA, has been analyzing images taken from an agency satellite program known as SERVIR which was launched from Marshall Space Flight Center in Huntsville, Alabama in 2005. Sever has used the images to further his theory—one also promoted by Jared Diamond in his popular book Collapse but not accepted by all Maya scholars—that what brought down the Maya was self-induced ecological disaster. The images indicate that the Maya used slash-and-burn agricultural practices that led to severe deforestation. They also drained the wetlands known as bajos, as evidenced by images of ancient drains, causing drought and resulting in an increase in temperature. The fate of the Maya is now often held up as a prime example of the risk of deforestation and climate change.
3. HOW AND WHERE THE EASTER ISLAND MOAI WERE MOVED
The iconic statues on Easter Island have fascinated archaeologists since they were first noted by a Dutch explorer in 1722. But the biggest mystery is how the Rapa Nui managed to transport these enormous monoliths from the quarries where they were made to numerous sites across the island without the help of large animals or cranes.
In 2012, Carl Lipo of California State University and Terry Hunt of the University of Hawaii used satellite imagery to trace the ancient path of the stones from the quarry to various points around the island, identifying seven major roads [PDF]. The discovery of these routes led Lipo and Hunt to suggest that the upright statues might have been “walked” to their destinations, using ropes to tilt and turn the monoliths into motion. To test out their theory, the National Geographic Society’s Expeditions Council funded an experiment in which a concrete 10-foot, 5-ton copy of a moai was constructed. Using strong ropes, 18 people were able to fairly easily walk the massive statue a few hundred yards.
4. THE LOST CITY OF IRAM/UBAR
Five thousand years ago, a grand city in the deserts of Oman formed the center of the valuable frankincense trade. Known as Iram or Ubar, the legendary city was mentioned in both the Koran and The Thousand and One Nights (a.k.a. The Arabian Nights). Yet no modern trace of this once great city could be found. Notable explorer T. E. Lawrence ("Lawrence of Arabia") referred to it as “the Atlantis of the sands,” and some historians began to doubt it had ever existed. The mystery of the lost city was sufficiently tantalizing to attract the notice of NASA, who agreed to scan the area with a shuttle radar system after being approached by filmmaker and explorer Nicholas Clapp.
A Challenger space mission in 1984 provided the perfect opportunity to scan the desert of Oman from space, searching for geological features hiding under the sand. The resultant pictures revealed ancient caravan routes, which would have been packed down over hundreds of years by the camel trains traveling between trade hubs, the intersections of these roads providing clues as to potential locations for a city. Using this information, archaeologists began to dig at promising locations, and in 1991 Clapp and his team uncovered a many-towered fortress (like that described in the Koran), which would have been the home of the king and hub for the storage of frankincense. This led them to believe that they had finally uncovered the lost city of Ubar.
Ancient sources claimed that the city had disappeared into the Earth after its citizens angered Allah with their lavish and sinful way of life. Evidence from the site in Oman suggests that the destruction of the city occurred due to the appearance of a giant sinkhole, explaining how this once great city was lost to the sands.