Finding Hidden Temples and Lost Nazca Lines with Satellites

In this episode of StarTalk, Neil deGrasse Tyson and co-host Chuck Nice explore the innovative field of space archaeology with guest Sarah Parcak. Space archaeology utilizes space-based assets like satellites and drones to map and analyze archaeological sites on Earth, helping to uncover hidden features beneath sand, soil, or dense vegetation. Parcak, an Egyptologist and professor at the University of Alabama, explains how these technologies have revolutionized the field, enabling precise targeting for ground excavations. The discussion also touches on the potential application of these techniques to other planets, highlighting the interconnectedness of scientific disciplines and the enduring human quest to understand our past and future.

• Definition: Space archaeology is the use of space-based assets to map archaeological sites.
• Applications: Mapping the moon, Mars, Venus, and Earth using space-based technologies.
• Collaboration: Increasing conversations with planetary scientists and NASA.

"Space archaeology is any use of space-based assets to map archaeological sites."

• Explanation: Space archaeology involves using satellites and other space technologies to identify and map archaeological sites on Earth and other planets.

• Credentials: PhD in Egyptology from the University of Cambridge, Professor of Anthropology at the University of Alabama Birmingham.
• Roles: Founding Director for the Laboratory for Global Observation, author of "Archaeology from Space," and the first textbook on satellite archaeology.
• Company: Founder and President of Global Explorer, a non-profit using technology to protect cultural heritage.
• Collaborations: Worked with NASA and the US State Department.

"I pronounce your last name correctly, hard C, Parcak, correct?"

• Explanation: Introduction to Sarah Parcak, her credentials, and her contributions to the field of space archaeology.

• General Description: Use of space-based assets like NASA satellites, commercial satellites, drone imagery, and data from airplanes to map archaeological sites.
• Applications: Locating whole archaeological sites, specific features, or ancient river channels.
• NASA Program: NASA has a space archaeology program that funds scientists to conduct this research.

"Space archaeology is the general term for any use of space-based assets to map archaeological sites."

• Explanation: Space archaeology encompasses various technologies to locate and map archaeological sites from space.

• Efficiency: Satellites can reveal features covered by sand, soil, or dense rainforest without physical excavation.
• Technological Tools: Use of light spectrum technologies like near-infrared to detect subtle differences in surface soils and vegetation.
• Planning: Helps archaeologists plan their fieldwork more effectively by providing detailed maps of sites.

"Satellites allow us to see size, scale, and extent of sites and better plan our season so that when we go there, we know exactly what we're looking for."

• Explanation: Space-based technologies enable archaeologists to identify and map sites more efficiently than traditional methods.

• Near-Infrared: Best for mapping differences in vegetation and vegetation health.
• Application: Detecting buried structures by observing how vegetation is affected by underlying features.

"Near-infrared is the best part of the light spectrum to map differences in vegetation and vegetation health."

• Explanation: Near-infrared technology helps in identifying archaeological sites by analyzing vegetation health and patterns.

• Location: Small island called Papor in Scotland.
• Discovery: Strong vegetation signature initially dismissed but later revealed a massive Viking Hall inhabited by royalty.

"It was this massive Viking Hall that was inhabited over hundreds of years by royalty and a king may have visited."

• Explanation: An example of how space archaeology can lead to significant discoveries, even when initial assessments are skeptical.

• Definition: Light Detection and Ranging, a technology that uses pulse beams of light to create 3D models of landscapes.
• Application: Effective in dense rainforests to map archaeological sites by removing vegetation layers in the data.

"LIDAR stands for Light Detection and Ranging... it sends down millions of pulse beams of light."

• Explanation: LIDAR technology allows archaeologists to create detailed 3D models of sites, even in dense vegetation.

• Future of Archaeology: Space archaeology represents a significant advancement in the field, offering new ways to explore and preserve cultural heritage.
• Interdisciplinary Collaboration: Continued collaboration with space agencies and technological advancements will further enhance the capabilities of archaeologists.

"Space archaeology is a significant advancement, offering new ways to explore and preserve cultural heritage."

• Explanation: The integration of space technologies in archaeology opens up new possibilities for discovery and preservation.

• LiDAR (Light Detection and Ranging) is used to create high-resolution digital elevation models.
• It is particularly effective in dense vegetation areas such as rainforests, where traditional ground surveys are challenging.
• LiDAR captures millions of data points per square meter, providing detailed topographic data.

"If there's a pyramid or canals or terracing, any kind of structures that indicate ancient settlement in that area, they are going to be obvious and clear in a way that isn't even when you're walking through the rainforest."

• LiDAR's ability to penetrate vegetation and capture detailed data from different angles makes it superior for archaeological surveys.

"You're catching it at different angles as it goes along, and so you end up with millions and millions of points."

• High-resolution LiDAR data allows for the identification of previously unknown structures and features.

"My colleagues at Tain University just used LiDAR data and they found 880,000 previously unknown structures and features around Tikal."

• Radar data can penetrate the ground to detect buried features, but its effectiveness is limited to dry environments and shallow depths.
• Thermal infrared data measures heat differences to identify buried chambers or tombs by detecting slight temperature variations.

"We can use radar data so that will pass through, that penetrates not very far, maybe a couple meters, and it has to be in dry environments."

• Different parts of the light spectrum (near, middle, far infrared) are used to detect vegetation, soil, and water differences.

"Thermal infrared measures heat differences, so if you have a buried chamber or tomb where the temperature is different, you're going to see that void."

• Active satellite data sends signals to the Earth's surface and measures the reflected signals, like LiDAR and radar.
• Passive satellite data receives light reflected off the Earth's surface, useful for analyzing different light spectrum parts.

"Passive is the most of the satellite data that I use, so it's receiving light that's reflected off your surface."

• NASA provides free satellite imagery data sets, while commercial satellite data is affordable for targeted archaeological surveys.

"NASA has put tens of millions of their satellite imagery data sets online... commercial satellite data, you can get a satellite image for a couple hundred dollars."

• Ground truthing involves visiting sites identified through remote sensing to verify and further investigate potential archaeological features.
• This method saves time and resources by allowing targeted fieldwork.

"Instead of spending six months in the field hacking through the rainforest, we're able to have a very targeted approach."

• The concept of ground truthing originated in military reconnaissance and has been adapted for archaeological use.

"Aerial Archaeology is the reason we have all aerial reconnaissance in the military. It started in World War I."

• The advancement in satellite and remote sensing technologies has democratized data access and increased efficiency in archaeological research.
• High-resolution satellite data has become more affordable and accessible, changing how archaeological surveys are conducted.

"When I was doing my thesis, high-resolution satellite data was $5,000 to $10,000 for a single image. Now we have Google Maps."

• Modern technology allows archaeologists to reanalyze old data and discover previously missed features.

"We have to go back and reanalyze all of our data because of what we missed."

• Remote sensing helps identify potential archaeological sites, but field verification is essential to confirm findings.
• Sometimes initial remote sensing data may lead to false positives, which are refined through further analysis.

"Maybe 85 to 90% of the time there's an archaeological site, and maybe one out of 10 is a false positive."

• Satellite imagery helps archaeologists make educated guesses about the nature of identified features based on known data from similar sites.

"We look at the tombs from the third Dynasty, fourth Dynasty, fifth Dynasty, and we're able to make pretty good guesses as to what the things are that we have found."

• The integration of LiDAR, radar, infrared, and satellite data has revolutionized archaeological surveys, making them more efficient and accurate.
• Ground truthing remains a crucial step in verifying remote sensing data and ensuring the reliability of archaeological findings.
• The democratization of data and technological advancements continue to enhance the field of archaeology, providing new opportunities for discovery and understanding of ancient civilizations.

• Satellite data aids in targeting excavation sites.
• The potential of satellite technology to uncover lost historical sites.

"Satellite data helps us to target what areas to excavate."

• Satellite imagery is crucial for identifying promising excavation areas.

• Ancient Egypt lasted approximately 3,000 years, with continuous occupation.
• The Nile's annual silt deposits contribute to the layering of historical sites.
• The extensive duration and population of ancient Egypt result in numerous undiscovered sites.

"If you think about how long ancient Egypt lasted, we're talking about a civilization that at its height lasted for approximately 3,000 years."

• The longevity of ancient Egypt implies a vast amount of historical data and sites yet to be uncovered.

"Imagine city and villages and towns and tombs and temples and pyramids for 2 million people over a 3,000 or more year period of time."

• The sheer number of people and duration of occupation in ancient Egypt means there are many undiscovered archaeological sites.

• Some cities have multiple layers of occupation due to their favorable locations.
• Modern cities often have ancient cities buried beneath them, creating "layered cities."

"Some cities in the world, you know, you both have traveled all over the place, and there are these magical cities that have these old vibes."

• Cities like Athens, Istanbul, and Rome are examples of layered cities with continuous human habitation over millennia.

"We call them palmes, so these layers and layers and layers of occupation."

• The concept of "palmes" illustrates the continuous human occupation and the resulting archaeological layers.

• Despite extensive research, only a minuscule fraction of archaeological sites in Egypt has been excavated.

"In the Egyptian Delta alone, we have excavated one 1,000th of 1% of the sites."

• This statistic underscores the vast potential for future discoveries in Egypt.

• Technology, like Google Earth, allows amateur archaeologists to contribute to discoveries.
• The Global Explorer project harnesses citizen participation in archaeology.

"Anyone with a computer can look at Google Earth, you know, it's on everyone's phones if you want it."

• The accessibility of satellite imagery democratizes the field of archaeology.

"We built an online citizen archaeology crowdsourcing platform."

• The Global Explorer project structures and guides public participation in archaeological research.

• The public's passion for archaeology can complement professional efforts.
• Structured citizen science projects can lead to significant discoveries.

"The crowd ended up finding almost 30,000 potential anthropogenic features."

• Citizen scientists identified numerous potential archaeological sites, showcasing the power of public involvement.

"This collaborative project helped to support great local archaeological work and gave them a new perspective."

• Citizen science projects can enhance professional archaeological research and lead to new discoveries.

• The value of expertise in archaeology is often underappreciated.
• The rise of amateur archaeologists can lead to conflicts with professional standards.

"People don't understand or appreciate that it takes years and years, decades of training."

• Professional archaeologists face challenges in conveying the importance of their expertise to the public.

"People like me get accused of gatekeeping or you think you're better than everyone else just because you know how to dig."

• There is a perception that professionals are gatekeeping, which can lead to misunderstandings about the field.

• Misconceptions about ancient civilizations, such as the idea that aliens built the pyramids, persist.
• Educating the public about the scientific basis of archaeological findings is crucial.

"I will prove that the pyramids were not built by aliens."

• Addressing and debunking pseudoscientific claims is an important aspect of public archaeology education.

"Things develop, and their social stratification and soon, you know, the wealthier people, the leaders, you bury them with pots and goodies."

• Explaining the logical progression of ancient practices helps to counteract pseudoscientific theories.

• The development of large structures in ancient societies was a gradual process marked by increasing complexity.
• The construction of pyramids began with simple stacked stone tombs and evolved over centuries.
• Imhotep, an ancient Egyptian architect, innovated by stacking stone-built tombs, leading to the creation of pyramids.

"So they get bigger and bigger and bigger over, you know, a 500-year period of time, and soon, you know, they're building huge structures out of mud brick. Aliens? No aliens."

• The quote emphasizes that the development of large structures was a gradual human achievement, not the result of alien intervention.

"Imhotep, the genius architect, the Steve Jobs of his time, takes this very large stone-built tomb and decides to stack them one on top of the other."

• Imhotep's innovation in architecture marks the beginning of pyramid construction, showcasing human ingenuity.

• Techniques from satellite archaeology are being adapted for planetary exploration.
• Collaboration with planetary scientists and organizations like NASA and SETI is increasing.
• The Drake Equation has evolved with the discovery of numerous exoplanets capable of supporting life.

"Everything you're doing here on Earth can now be applied when we're mapping the moon or Mars or Venus."

• Archaeological techniques used on Earth are now being considered for mapping extraterrestrial terrains.

"We didn't know how many exoplanets there were capable of supporting life... now there's hundreds out of a catalog of nearly 6,000."

• The discovery of exoplanets has expanded the scope of the Drake Equation, indicating a higher probability of extraterrestrial life.

• Archaeology provides a framework for reconstructing ancient civilizations, which can be applied to potential extraterrestrial findings.
• The study of civilizations involves understanding their development, which can offer insights into alien societies.

"Archaeology provides us a framework to reconstruct how entire civilizations evolved, using the huge intellectual capital of invested brains thinking about that."

• Archaeology's methods can help decode the history and development of potential extraterrestrial civilizations.

• Research into life forms in extreme environments on Earth, such as deep-sea vents, can inform the search for extraterrestrial life.
• The adaptability of life forms like octopuses, which build structures, offers a model for imagining alien life.

"Could beings exist that have evolved to live in extreme temperatures? Which is why we're studying life around heat vents deep in the ocean."

• Studying extreme environments on Earth helps scientists hypothesize about the conditions for life on other planets.

"Octopuses, they make houses. It's amazing. They construct their own little mini-apartments."

• The behavior of octopuses in building structures provides a parallel for imagining how alien civilizations might adapt and construct their habitats.

• Space archaeology includes studying human-made structures in space, like the ISS, to understand how they evolve over time.
• The ISS serves as a microcosm for studying the evolution of human culture and technology in space.

"We have the space station, and we have to figure out what do people leave behind, what's the ephemeral evidence, what are things that we need to consider."

• Studying the ISS helps archaeologists understand how human activities and technologies evolve in a confined space environment.

• There is potential for finding fossil remains of Earth life on the Moon, transported by asteroid impacts.
• The Moon's lack of erosion and weathering makes it a good candidate for preserving ancient fossils.

"People have considered looking for fossil remains of life on the Moon from ejected rocks from asteroid impacts on Earth."

• The idea of finding Earth-origin fossils on the Moon opens a new frontier for understanding the history of life on Earth and its potential spread through space.

• Despite challenges like climate change, war, and disease, human culture and civilization persist.
• The concept of continuity is central to understanding the resilience and longevity of human societies.

"Wherever you go, people last. Kings may stop ruling, there may be environmental change, climate change, war, disease, but culture persists, people persist."

• The persistence of human culture despite various challenges offers hope and a positive outlook on the future of humanity.

• Sciences are interconnected, and methods from one field can often be applied to another.
• The division of sciences into categories is a human construct, and nature does not adhere to these boundaries.

"We divided the science into these categories; nature didn't do that. We did."

• The interconnectedness of scientific disciplines highlights the importance of cross-disciplinary collaboration and innovation.

"Tactics, methods, and tools of the archaeologist can be applied to space and vice versa."

• The application of archaeological methods to space exploration exemplifies the potential for cross-disciplinary advancements in understanding our universe.