Tähdistöjä

Tähdistöjä are patterns of stars visible in the night sky. Historically, these patterns were named and used for navigation, agriculture, and mythology by various cultures. While the stars within a tähdistö may appear close together from Earth, they are often vast distances apart in three-dimensional space. The International Astronomical Union (IAU) officially recognizes 88 tähdistöjä that cover the entire celestial sphere. These officially defined regions are used by astronomers to map and locate celestial objects.

Some of the most well-known tähdistöjä include Ursa Major, which contains the Big Dipper asterism, Orion, recognizable by its prominent belt, and Cassiopeia, a distinctive W or M shape. The visibility of a tähdistö depends on the observer's latitude and the time of year. Many tähdistöjä have names derived from Latin, often representing animals, mythological figures, or objects. Ancient civilizations developed their own sets of tähdistöjä based on their cultural contexts and observations of the night sky. Modern astronomy uses tähdistöjä as a framework for organizing and cataloging stars and other celestial bodies, providing a standardized system for communication among astronomers worldwide.