Astronomy

 Vocabulary List Number 405 v.0.5 with 13 entries made up of 2 chapters with 10 definitions and 3 examples. Updated at June 11, 2026.

     1. Main Definition

1. 
   Brittanica: astronomy |n| 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, astronomy was primarily concerned with noting and predicting the positions of the Sun, Moon, and planets, originally for calendrical and astrological purposes and later for navigational uses and scientific interest. The catalog of objects now studied is much broader and includes, in order of increasing distance, the solar system, the stars that make up the Milky Way Galaxy, and other, more distant galaxies. With the advent of scientific space probes, Earth also has come to be studied as one of the planets, though its more-detailed investigation remains the domain of the Earth sciences. (From Brittanica. June 11, 2026.)
2. Cambridge: astronomy |n| the scientific study of the universe and of objects that exist naturally
3. in space, such as the moon, the sun, planets, and stars. (From Cambridge Dictionary. May 14, 2025.)
4. Google IA: astronomy 1 |n| a natural science dedicated to observing and analyzing objects in the cosmos. (From Google IA. May 11, 2026.)
5. Google IA: astronomy 2 |n| is the scientific study of everything beyond Earth's atmosphere, including planets, stars, galaxies, comets, and black holes. It uses physics, chemistry, and mathematics to investigate the origin, evolution, and physical properties of celestial objects and the universe itself. (From Google IA. May 12, 2026.)
6. Merriam Webster: astronomy |n| the study of objects and matter outside the earth's atmosphere and of their physical and chemical properties. (From Merriam Webster Dictionary. May 14, 2026.)
7. Oxford Learner's: astronomy |n| the scientific study of the sun, moon, stars, planets, etc. (From Oxford Learner's Dictionary. May 26, 2026.)
8. Oxford Dictionary: astronomy |n| the branch of science that deals with celestial objects, space, and the physical universe as a whole. (From Oxford Dictionary. May 26, 2026.)
9. Reverso: astronomy |n| scientific study of stars, planets, and space. (From Reverso Dictionary. June 11, 2026.)
10. Wikipedia: astronomy |n| |n| a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry to explain their origin and their overall evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, meteoroids, asteroids, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond Earth's atmosphere. Cosmology is the branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Egyptians, Babylonians, Greeks, Indians, Chinese, Maya, and many ancient indigenous peoples of the Americas. In the past, astronomy included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars. Astronomy is one of the few sciences in which amateurs play an active role. This is especially true for the discovery and observation of transient events. Amateur astronomers have helped with many important discoveries, such as finding new comets. (From Wikipedia. May 14, 2026.)

      2. Examples

1. 
   "For years, it's been an accepted tenet of astronomy that, with the exception of Pluto – infamously now classified as a dwarf planet – none of these worlds were likely large enough to sustain an atmosphere." — From Eric Lagatta, USA Today, 8 Jun 2026.)
2. "The project is expected to represent a giant leap forward in astronomy she developed a passion for astronomy at just the age of five." (From Oxford Dictionary. May 26, 2026.)
3. "Astronomy helps us understand the universe." (From Reverso Dictionary. June 11, 2026.)