astronomy

noun as·tron·o·my \ ə-ˈsträ-nə-mē \

|Updated on: 11 Jun 2018

Editor's Note: The Difference Between astronomy and astrology

Definition of astronomy

plural astronomies

: the study of objects and matter outside the earth's atmosphere and of their physical and chemical properties

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Recent Examples of astronomy from the Web

Rasmussen is taking an astronomy final a day early.

— jon j. kerr, chicagotribune.com, "'No one knows who we are:' OPRF boys volleyball comfortable as underdog at state," 31 May 2018
In June, the museum, with credits coming from Baker University, will begin offering teachers in the upper elementary and middle school grades a weeklong course on using projects to teach astronomy.

— eric adler and steve vockrodt, kansascity, "After losing millions, can Prairiefire dinosaur museum in Johnson County evolve? | The Kansas City Star," 18 May 2018
This makes astronomy very democratic—anyone who wants to can reanalyze almost any data set that makes the news.

— eileen meyer, Smithsonian, "Big Data is Transforming How Astronomers Make Discoveries," 15 May 2018
This torrent of discovery has made exoplanetology one of the most exciting fields in astronomy.

— The Economist, "The search for exoplanets moves to Earth’s back yard," 19 Apr. 2018
Officials are developing astronomy-themed events as well as scoping out extra camping space since reservations are piling up.

— morgan watkins, The Courier-Journal, "Why the Great American Eclipse a really big deal in Kentucky," 2 Sep. 2016
Just think of biology before and after the microscope or gene sequencing, or of astronomy before and after the telescope, or of particle physics before and after colliders or fast electronics.

— marcelo gleiser, Scientific American, "How Much Can We Know?," 8 May 2018
Looking for the first stars and black holes has long been a goal of astronomy.

— david grossman, Popular Mechanics, "The James Webb Telescope Could Find the Very First Stars," 25 Apr. 2018
Over roughly the same time period—from 1960 to 2013—the percentage of women holding science jobs rose from 28% to 49% in biological science, from 8% to 35% in chemistry, and from 3% to 11% in physics and astronomy.

— katie langin, Science | AAAS, "What does a scientist look like? Children are drawing women more than ever before," 20 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'astronomy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

The Difference Between astronomy and astrology

Some may find it easy to confuse astronomy and astrology. At one time, these two words actually were synonymous (that is, astronomy once meant what astrology means today), but they have since moved apart from each other. In current use, astronomy is concerned with “the study of objects and matter outside the earth's atmosphere,” while astrology is the purported divination of how stars and planets influence our lives. Put bluntly, astronomy is a science, and astrology is not.