The astronomical unit (AU) is a measure of distance equal to the distance between the Earth and the Sun, approximately 93 million miles (150 million km). The AU has been estimated for centuries, with modern measurements being the most accurate. The current definition is the distance from the center of the Sun at which a […]
Astronomical instruments are used to study celestial objects and are divided into observational and recording tools. Telescopes are a basic instrument, with different types using lenses or mirrors. Radio telescopes collect radio waves and interferometers determine size. Different instruments are used depending on the celestial phenomenon being studied. An astronomical instrument generally refers to a […]
