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the Sun in ShadesDo you like to travel? Come along and we'll visit people and places from the past, stopping to have some fun with me, the sun! Let's go back in time. We know that for ages, people all over the world have observed me, and there have been lots of ideas about what I am.




map of Earth

"community of sunwatchers" icon What is a community of sunwatchers?

We know that people have lived on the Earth for thousands of years. They have lived in small and large communities, each with its own ways of doing things. We know this by the things these communities leave behind, sometimes hundreds of years after the people who lived there are gone. These things are often called artifacts. Artifacts come in all sizes. Some are as small as a weaving tool and can fit easily into your hand. Some artifacts weigh many tons. Some communities have left enormous artifacts, like the Native American Anasazi people who created a great city now in ruins. As people have investigated these artifacts, we now understand how advanced these people were. A community's artifacts can show us their art, their tools for daily life, their homes, and their belief systems. All of these things make up what we call a culture. A culture represents a group of people who live in a particular period, who form a community, who share and practice traditional activities, who share a belief system, and who may share the same ancestors. 

laptop and backpackHundreds--even thousands--of years from now, what will the artifacts that YOU leave behind tell future generations about your culture?


what of culture icon What does culture have to do with science?

People who study artifacts over long periods of time are known as archaeologists. Their studies show us that the sun has been a powerful and mysterious force in people's lives throughout history--going back thousands of years! Communities of sun watchers all over the world have used the sun as a scientific tool to determine when to plant their crops, tell time, explain natural marvels, and understand the world. Like culture, science forms its understanding of the sun based on the known facts at that time. We have a lot of information on the sun today that has been enhanced over time by using the contributions of people around the world from today and from the past.

"what is archaeology" icon Is archaeology the only way to study cultures?

Archaeoastronomy is another way to study cultures and their histories. Archaeoastronomers study archaeology, anthropology, and mythology as they are linked to astronomy. They believe that by blending both material things and oral stories, they can get a bigger picture of a community of people, and how they interacted with their world. Before archaeology, and even before world cultures recorded their history in writing, oral story telling was the way people preserved history and passed down knowledge. Anxious not to lose their rich heritage, most cultures assigned one person to serve as a keeper of the stories. This was a highly regarded social position that brought great responsibility. For these storytellers, truth in history was the goal. 

Around 7000 years ago--long before the pyramids were constructed in Egypt--people built structures aligned to the sun and stars that served much like a sundial. They are the oldest dated artifacts left to us by a culture. These stones are aligned with the sun and the moon, making us believe they were built in order to track time and predict the changes of the seasons.

oldest known sundialWhere is the oldest known sundial? It's in Africa, in southern Egypt, at Nabta, and dates back over 6,000 years! The Standing Stones at Nabta was built by a community of people who lived off the land and its water. When the people of Nabta moved on, they left the oldest known megalith on Earth, that covers approximately one square mile.


Nabta consists of a stone circle. The circle is created by a series of flat and Nabta sundial tomb-like stone structures with five lines of standing and leaning megaliths extending outward and beyond the main circle. Some of the stones used at this site are over nine feet tall and were transported at least two miles. The people who created this megalith used and positioned the stones in ways to help them mark the passing of seasons and to determine rainfall for the planting of crops. The site also contains all kinds of cultural artifacts, including small, fire-blackened stones from ancient hearths built along the ancient lakeshore as well as manos (hand-held stones for grinding grain), metates (the stone on which the grains were ground), pieces of decorated pottery jars, grains of sorghum, carved, decorated ostrich eggshells, numerous bones of cattle, a sculptured rock resembling a cow. What do these artifacts, including the placement of the standing stones, tell you about the people of Nabta and the things or practices that they valued as a culture? The Standing Stones at Nabta served very much like another stone structure built later in England. We call these structures megaliths.

"What are megaliths" icon What are megaliths?

Mystery surrounds the giant stone structures (or megaliths) that were built by ancient cultures. The most famous of these megaliths is Stonehenge, located on the Salisbury plain in England. However, there are many megaliths around the world from Europe to Africa to America. Three types of megaliths are: 1) solitary menhirs (large, single, upright stones), 2) circular menhirs, (stones that form a circle), and 3) temples (generally built for worship).

Stonehenge from skyHow was Stonehenge (the name means hanging stones) built with stones that were not found in the area at that time? The Heel Stone (the stone that some people believe defines the direction of sunrise at the time of solstice) weighs in at 35 tons! (Learn more about solstices and the seasons here.) According to local legend, the stones were moved magically by Merlin, the magician from King Arthur's court. No one knows for certain that Stonehenge was built to mark time. We do know that it took a long time to build and is made up of a series of earth, timber, and stone structures that were changed and remodeled over a period of more than 2000 years. There are 91 stones that make up Stonehenge. From the air, you can see that most of the stones are located within a large ditch. Within this outermost circle are 56 round patches of white chalk that modern astronomers can use to predict a solar eclipse. At the center point you can see the sunrise above the heel stone that is located outside of the circular ditch.

"how did" iconDid you know that over 3000 years ago, people in the United States began building a large timepiece?

The Big Horn Medicine Wheel, located near Sheridan, Wyoming, is one of The Big Horn Medicine Wheelseveral stone circles throughout the continental United States and Canada. It is believed to have been originally constructed by Native Americans in 1500 B.C. with construction ongoing through 500 A.D. Although the information about the medicine wheel is recent, there is evidence that people used it to predict seasonal changes. When you stand in the middle of the wheel, called the hub, an alignment scheme becomes evident. The spokes on the wheel correspond to various celestial phenomena like the summer solstice and the rising of stars-Rigel, Aldebaran, and Sirius. These events occur during times when this area could have hosted nomadic people. It is believed that the people used this eel to determine when it was time to move to another camp site.

"We've seen menhirs" icon We've seen menhirs. How do sun temples fit in?

the Sun with shades onSun temples are found all over the world. These temples (many of which are now in ruins) show us that ancient people observed and revered the sun. You can find sun temples in many countries, including India, Pakistan, Egypt, Central America, and Mexico.

Tamil Nadu TempleThe sun is believed to be the source of life for the people of India. Over a thousand years ago, temples and shrines were built in the Tamil Nadu (known as the "Land of the Temples" region. On days close to the equinox the sun shines at dawn or sunset on the main deity--generally the benevolent sun god, Surya--of that temple. One of the most well-known temples of India is Konark in Orissa on the eastern seashore of the country. The present temple at Konark, also known as the Black Pagoda, was built over 700 years ago. Konark resembles a great chariot with seven horses and 24 wheels with eight spokes in each wheel. It is believed that the seven horses represent the days of the week. Different sources report that the wheels represent either the hours of the day or each month in the Hindu calendar with the spokes being one of the part of the Hindu day.

"Other than megaliths" icons Other than megaliths, are there any other ways that we know ancient cultures marked time?

Pyramid at Chichen ItzaAround 700 years ago, in North America, three different communities of people built observatories to mark time with the sun. One of these is the Pyramid at Chichen Itza. In order to predict events on the solar calendar, like the equinoxes, solstices, and eclipses, the Mayans built observatories. One such observatory, called El Castillo, was built in an area called Chichen Itza. It is believed to be a temple, or a place of sun worship. This pyramid has a square base with nine terraces built upward. Each terrace contains a set of 18 steps, which corresponds to the 18 months of the Mayan Calendar. There are 91 stairs on each side of the pyramid, totaling 364 steps. By adding the platform to this figure, the total is 365 representing the days in a solar year.

Chaco Canyon cave paintingsAnasazi Indians traveled from Mexico to present day northern New Mexico. They used their knowledge to create calendars and great observatories. At one time, Chaco Canyon was a huge center of trade and industry. Chaco Canyon contains rocks recording stories about the sun. One of the more famous ones is the Sun Dagger at Fajada Butte. Fajada Butte is a shrine two spiral petroglyphs that contains two spiral petroglyphs. On the days close to the summer solstice around the noon hour, a band of light bisects the large spiral. Near the winter solstice around the noon hour, two bands of light appear on either side of the large spiral. During the spring and fall equinoxes, a small band of light bisects the smaller spiral while a larger dagger of light moves to the right of the center of the larger spiral.

Hovenweep CastleHovenweep Castle Hovenweep National Monument is located in southern Utah in the United States. Hovenweep Castle, named after the medieval castles that are found throughout Europe. One room in the castle, known as the sun room, is the room that archaeoastronomers believe the Anasazi used to mark equinoxes and solstices. During the dates near the summer solstice, at sunset light enters this room of the castle through a hole shining on a threshold of a doorway. Likewise during the winter solstice sunlight enters another hole and falls on the edge of another doorway. It is believed that these people used this system to determine planting dates and for priests to plan ceremonies.

The sun clock at Kochi Castle400 years ago, in Japan, people built a sun clock to use it as a time piece.The sun clock at Kochi Castle, Japan is located on the west entrance of the castle and one of many such time pieces found throughout Japan. There is evidence that suggests that this sun clock was influenced by the clepsydra (water clock) used in China during the latter part of the seventh century. The people of this time are presumed to have used the sun clock as a way to standardize time in their communities. People could walk up to the clock and estimate how much time there was before or after the noon hour. Although the sun clock is not precise in telling what time it is, it is more precise than the previous ways of telling time. Earlier people used the the position of the sun to tell the approximate time. For example, if people were setting up a time to meet, they might say that they would meet at a certain place when the sun reached the tip of the horizon. 

"ancient cultures" icons So how did ancient cultures know what time it was?

One way of dividing up the day would be to observe the position of the sun in the sky. Because of the rotation of the Earth, the sun appears to move across the sky, rising in the east and setting in the west. It is not safe to look at the sun, so a simple device that used a shadow was developed to safely observe the movement of the sun. The first sun dial was probably just a stick that was put into the ground. At sunrise the shadow of the stick was long and pointed toward the west. During the morning the shadow would get shorter and by noon it would be at its smallest length, perhaps pointing slightly to the north in the Northern Hemisphere. After noon the shadow would grow toward the east and as sunset approached it would grow long once again. Sundials are the oldest known instrument for telling time. They were probably invented in Egypt where the day was divided into twelve equal hours as early as 6000 years ago. Sundials normally consist of a dial Modern Sundialplane (face) and gnomon (stick). The horizontal dial plane is marked off into hours and quarter hours. The vertical gnomon, which casts a shadow onto the dial plane, is usually triangular. The angle of the gnomon is equal to the latitude of its location. In the Northern Hemisphere the gnomon points to the north, and in the Southern Hemisphere it points to the south. Of course there are limitations to sundials. It is difficult or impossible to use a sundial on a cloudy day or at night. They are still used today as decorative pieces in many outdoor locations, including gardens and parks.

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planet EarthWe've been all over the world, visiting places and viewing artifacts of ancient people who observed the sun. We know this by the artifacts that they left behind. But are there other ways that ancient people interacted with the sun? Of course! Ancient Greeks and Romans explained the sun with mythology while others explained it with cultural stories. Learn more about stories of origins, mythology, and the sun here.


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