Cassiopeia , in astronomy , a constellation of the northern sky easily recognized by a group of five bright stars forming a slightly irregular W. This constellation also contains the prominent radio source Cassiopeia A , a supernova remnant , and the nearby galaxies Maffei I and II. In Greek mythology , Cassiopeia was the queen of Ethiopia whose daughter Andromeda was saved by the hero Perseus from being sacrificed to a sea monster. Article Media.
Info Print Cite. Submit Feedback. Thank you for your feedback. Cassiopeia astronomy. See Article History. Learn More in these related Britannica articles:. 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, astronomy was primarily concerned with noting and predicting the positions of the Sun, Moon, and planets, originally for….
Constellation , in astronomy, any of certain groupings of stars that were imagined—at least by those who named them—to form conspicuous configurations of objects or creatures in the sky. Constellations are useful in tracking artificial satellites and in assisting astronomers and navigators to locate certain stars.
Star , any massive self-luminous celestial body of gas that shines by radiation derived from its internal energy sources. Of the tens of billions of trillions of stars composing the observable universe, only a very small percentage are visible to the naked eye.
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