Astronomy is one of the oldest sciences. It has been studied by many ancient cultures. Greek philosophers began to formulate models to explain their place in the universe. Astronomers during the Islamic civilization carried forth the Greek knowledge of the skies and further laid the foundation for the study of the sky and the science of astronomy. Other cultures around the world placed a significant emphasis on the observation and study of the sky. Some, such as the Egyptians, built grand monuments aligning with celestial events. Stonehenge is an ancient monument that is believed to have been built in position with the rising and setting of the Sun at particular times of the year. Throughout the centuries, the sky and the objects and events within it have remained a spectacle that has been continually studied and that has continually influenced cultures of antiquity and modern times.