Final answer:
An artist might have separate sundials for each season to accurately depict the sun's changing position due to the 23.5° tilt of Earth's axis. These variations are critical for precision in timekeeping and were historically significant for calendars and cultural events.
Step-by-step explanation:
The reason an artist might have a separate sundial for each set of three months or each season is a) To accurately depict the changing position of the sun throughout the year. Sundials can be affected by the 23.5° tilt of Earth's axis of rotation, meaning the sun's path and resulting shadows will vary with each season. During the summer solstice, for example, the sun is high in the sky and sundials need to account for longer days and more direct sunlight. Conversely, in the winter solstice, the sun is lower and the days are shorter, requiring adjustments to the sundial's design. To ensure precise timekeeping, separate sundials may be tailored to these seasonal variations.
Historically, sundials have been an important tool for keeping time and informing agricultural and religious practices. The Babylonian priests, for example, designed the first calendar by tracking the days between solstices and equinoxes. Archaeologists have also discovered that ancient civilizations, like those in Chaco Canyon, used sundials to mark significant celestial events such as solstices and equinoxes. Moreover, sundials have evolved over time, from early versions measuring unequal hours to more recent ones with a gnomon that aligns with the celestial pole.