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Observational astronomy is focused on acquiring data from observations of astronomical objects. Professional astronomy is split into observational and theoretical branches. Nowadays, professional astronomy is often said to be the same as astrophysics.
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In the past, astronomy included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars. These include the Babylonians, Greeks, Indians, Egyptians, Chinese, Maya, and many ancient indigenous peoples of the Americas. The early civilizations in recorded history made methodical observations of the night sky. Īstronomy is one of the oldest natural sciences. Cosmology is a branch of astronomy that studies the universe as a whole. More generally, astronomy studies everything that originates beyond Earth's atmosphere. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets. It uses mathematics, physics, and chemistry in order to explain their origin and evolution.
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The Paranal Observatory of European Southern Observatory shooting a laser guide star to the Galactic CenterĪstronomy (from Ancient Greek ἀστρονομία ( astronomía) 'science that studies the laws of the stars') is a natural science that studies celestial objects and phenomena.
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