Construction of Great Pyramid of Giza may have started on August 23, 2470 B.C.

Washington, September 22 (ANI): A controversial new research has placed an exact date on the start of the ancient construction project of the Great Pyramid of Giza, as August 23, 2470 B.C.

According to a report in the National Geographic News, a team of Egyptian researchers arrived at the date based on calculations of historical appearances of the star Sothis, which is today called Sirius.

Every year around the time of the Nile River floods, Sothis would rise in the early morning sky after a long absence.

"The appearance of this star indicates the beginning of an inundation period" for the Nile, said team leader Abdel-Halim Nur El-Din, former head of Egypt's Supreme Council of Antiquities.

Throughout their history, "Egyptians started their main buildings, the tombs, and the temples at the beginning of the inundation"-an auspicious time, since floodwaters brought fresh soil, maintaining the region's fertility.

In addition, pharaohs always started building their tombs at the starts of their rules.

Khufu, the pharaoh meant to be buried in the Great Pyramid, took power in 2470 B.C., according to Nur El-Din and colleagues.

The researchers therefore compared the modern calendar, the ancient Egyptian calendar, and the cycle of the star to find the exact day Sothis would have appeared that year.

The team believes the ancient Egyptians observed the star from July 17 to 19, and the inundation period began 35 days later-on August 23.

"Using Sothis's arrival to keep track of the annual Nile floods made sense," said Mark Hammergren, an astronomer at the Adler Planetarium in Chicago.

"It happens at about the same time every solar year, so it corresponds to the seasons, and it provides them a good fixed date," he added.

Hammergren agrees with the days Nur El-Din's team calculated for Sothis, based on other researchers' estimates for the dates the star would have risen during ancient Egyptian times. (ANI)