When we think of archaeologists, we tend to picture them sifting through dirt in search of ancient treasures. But that image is outdated. Today's archaeologists are more likely to use technology than shovels.

Some of this technology is familiar. The most common tools include laptop computers and cell phones. But archaeologists use a wide range of high-tech solutions to help them find remains of past cultures.

Some of the most useful tools are those that let archaeologists study from a distance. Being able to examine an area without ever setting foot on it is helpful. It saves time and helps control costs.

There are many ways to study sites from afar. Archaeologists often review pictures taken by satellites. They hunt for unusual images. Perhaps a cliff with ridges that are too perfectly regular. Or a small mound that appears in the middle of a flat field. These oddities suggest humans may have changed the land's natural geography. So these are new places worth exploring.

An airplane or helicopter can provide a closer look. Archaeologists often fly above sites to snap pictures from the air. It's also helpful to use air travel to explore sites that are too difficult to reach by foot. These areas can be photographed with balloons or unmanned flyers.

Different Aerial Angles Are Critical

Pictures taken from overhead are especially useful. They provide a different view from what can be seen at ground level. And by using an airplane or helicopter, archaeologists can cover great distances in a short time.

It's important that these images include different angles. Otherwise, they can be misleading. Imagine taking a photo looking straight down from the sky. This angle makes everything appear flat, like it's all at the same level. The same photo taken on an angle provides a completely different view, revealing hills and valleys.

Photography is a perfect tool for recording what is visible. There are other technologies, however, that help with what's invisible.

Using tools that measure temperature, for example, archaeologists can find hidden patterns in the ground. A team of archaeologists recently used this procedure to study Chaco Canyon in New Mexico, United States. The site is famous and has been studied for decades. But the team wondered if there was more to uncover. They began measuring temperatures near ground-level, plotting the data on a map. To their surprise, the data revealed a web of roads that had never been recorded.

Infrared Light Pierces the Ground

Sometimes archaeologists hunt for specific light waves. For example, infrared light is normally invisible to humans. But it uncovers a sign of plant life. So archaeologists use tools that make infrared stand out.

To find what's underground, archaeologists use technology that measures invisible particles. These systems are similar to medical x-rays. They send particles through solid material and record the reaction. That reaction is what produces the image.

The U.S. space agency, NASA, used one of these systems on the space shuttle. As the shuttle orbited Earth, it mapped an area in northern Africa, near the Nile River. The map uncovered details of ancient rivers that were never seen before. Scientists believe these waterways may explain the Nile's bend.

Echoes from Underground

There is another high-tech system that is used closer to the ground. This tool sends pulses through the ground's surface and measures how long it takes for the echo to return. That can tell archaeologists just where an object is buried. This is helpful when organizing different stages of a dig.

Once a site has been mapped, it can be thoroughly examined. Objects that are dug up are sent to laboratories for further study. Small samples are tested with different chemicals to identify properties like age and makeup.

In the past, properties like these were generally left to guesswork. But with the help of technology, today's archaeologists have data and facts to enhance their explorations. The days of digging and hoping to get lucky are a thing of the past.