4 days ago · Astronomy, science that encompasses the study of all extraterrestrial objects and phenomena. Since the late 19th century, astronomy has expanded to include astrophysics, the …

ASTRONOMY meaning: the scientific study of stars, planets, and other objects in outer space

The study of astronomy involves all of the objects outside Earth’s atmosphere. These include the Sun, Moon, planets, stars, galaxies, and all other matter in the universe.

Astronomy, science that encompasses the study of all extraterrestrial objects and phenomena. Until the invention of the telescope and the discovery of the laws of motion and gravity in the 17th century,...

Jan 28, 2026 · The rate at which galaxies and large structures composed of galaxies coalesced from density fluctuations in the early universe indicates that the nonbaryonic dark matter is relatively “ …

Before the dawn of history someone noticed that certain celestial bodies moved in orderly and predictable paths, and astronomy—an ancient science—was born. Yet some of science’s newest …

Jan 30, 2026 · The Sun, Moon, and brightest planets were visible to the naked eyes of ancient astronomers, and their observations and calculations of the movements of these bodies gave rise to …

Jan 20, 2026 · Astronomers define stellar brightness in terms of magnitudes: the apparent magnitude (the perceived and measured brightness of a star) and the absolute magnitude of the brightness of …

Jan 8, 2026 · While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any …

While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions. Britannica Editors. …