How did the ancient Egyptians use their knowledge of the stars and constellations?

The ancient Egyptians were some of the first people to observe and record the movements of the stars and constellations. Their knowledge of astronomy was intimately tied to their religion and the belief that the stars and sky were divine.

One of the ways that the ancient Egyptians used their knowledge of the stars and constellations was to develop a calendar based on the movement of the stars. They divided the year into 365 days and grouped them into 12 months of 30 days each, with an additional five days added at the end of the year to align the calendar with the solar year.

Another important use of astronomy in ancient Egypt was for navigation. The stars were used to guide ships on the Nile River and to navigate the vast deserts that surrounded Egypt. The constellation of Orion was particularly important in this regard, as it was used to guide ships from the Mediterranean to the Red Sea.

The ancient Egyptians also believed that the stars were the home of the gods and that they could communicate with them through certain constellations. For example, the constellation of Orion was associated with the god Osiris, who was believed to have been buried in a tomb that aligned with the three stars that make up Orion's belt.