It has long been known that the ancient Egyptians studied the sky very closely for their calendars and timekeeping. Now archaeologists in the Nile Delta have discovered the remains of an astronomical observatory from the 6th century BC for the first time. It is the oldest and largest of its kind and includes, among other things, a sundial and a stone instrument for observing the course and altitude of the sun. The observatory, which was once integrated into a temple, was probably used to determine ritually and culturally important dates.
Like other early cultures, the Egyptians began to observe the movement of the sun and moon very early on and to use their cycles for their calendars and timekeeping. This is evidenced by written records on papyrus and stone inscriptions in temples and tombs. According to these, Egyptian astronomers may have even discovered and described variable stars around 3,000 years ago. Many Egyptian temples and tombs are also aligned according to astronomical aspects such as the solstices.
850 square meter observatory
Now, finds at an excavation site in the Nile Delta are providing new clues as to where and how the Egyptians followed celestial events. The site is the Tell el-Fara’in settlement hill, located around 80 kilometers east of Alexandria, where ruins from the Bronze Age to the Ptolemaic era have already been discovered. The latter also includes the Temple of Buto from the 6th century BC. In the southwest corner of this temple, archaeologists have now discovered the remains of an astronomical observatory. The newly uncovered area covers around 850 square meters and several rooms made of mud bricks, an L-shaped central hall lined with columns and an entrance facing east towards the sunrise. This is the oldest and largest observatory from this period, reports the Egyptian Antiquities Authority.
In the rooms of the observatory, the archaeologists came across several astronomical instruments. “Although these tools are comparatively simple, they already allowed the precise observation and measurement of solar calendar dates that were important for religious rites, royal coronation ceremonies and even agriculture,” reports Mohamed Ismail Khaled, Secretary General of the Antiquities Authority. One of the outstanding finds is a large sundial made of large limestone blocks, with 4.80 meter long stone slabs lying in a row underneath. On top of these slabs lie five other flat blocks, three placed vertically and two lying horizontally. “We assume that these blocks once had notched lines to measure the directions of the sun and shadow and to track the movement of the sun throughout the day,” explain the archaeologists.
Inclinometer and observation tower
Another astronomical instrument consists of a three-part ensemble of stone blocks, also carefully arranged, with an upright stone in the center and two round stone slabs to the north and west. According to archaeologists, this trio served Egyptian priests and astronomers as a measuring instrument for the sun’s inclination – its height above the horizon. Other finds included the stone foundations of a small observation tower and storage rooms built of mud bricks. Relics of wall paintings depicting various deities and astronomical motifs can also be seen on the walls of the central hall and some other rooms, the antiquities authority reports.
“This discovery underlines the advanced astronomical knowledge of the ancient Egyptians, including their ability to determine the solar calendar and dates of religious and agricultural significance,” says Mohamed Ismail Khaled. In addition, the observatory demonstrates the simple but precise means by which the Egyptians conducted their astronomical studies.
Source: Supreme Council of Antiquities, Egypt State Information Service