ephemeridejä

Ephemerides, often referred to as *ephemeridejä* in Swedish, are astronomical tables or data sets that provide the positions of celestial objects—such as the Sun, Moon, planets, and stars—at specific times. These calculations are essential for navigation, astronomy, and timekeeping, as they allow observers to predict the apparent motion of objects in the sky. Ephemerides are typically compiled using precise mathematical models that account for gravitational influences, orbital mechanics, and other factors affecting celestial motion.

Historically, ephemerides were published in printed form, such as almanacs, which listed daily or hourly positions for navigation or agricultural purposes. Modern ephemerides are now generated digitally using high-performance computing, offering greater accuracy and accessibility. They are widely used in fields like space exploration, satellite tracking, and amateur astronomy, where knowing the exact location of celestial bodies is critical.

The term *ephemeridejä* specifically refers to the Swedish plural form of *ephemerid*, which derives from the Greek word *ephemeris* (ἐφημερίς), meaning "daily." These tables often include additional data, such as lunar phases, eclipses, and planetary conjunctions, making them valuable references for both professionals and enthusiasts. While traditional almanacs remain popular among hobbyists, digital ephemerides—available through software and online databases—have largely replaced printed versions due to their convenience and precision.