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Northern Hemisphere, John Flamsteed
Northern Hemisphere, John Flamsteed, Atlas Coelestis, London: 1929. Image courtesy of Department of Special Collections, University of Wisconsin-Madison Memorial Library.
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What is a constellation?
A constellation is a group of stars that, when seen from Earth, form a pattern. All the stars in the sky are officially divided into constellations.

How many constellations are there?
Astronomers officially recognize 88 constellations covering the entire sky in the northern and southern hemispheres.

Who invented the constellations?
Our modern northern hemisphere constellation system comes to us through the ancient Greeks, who acquired knowledge from Egyptians of the original systems for organizing the stars developed in Sumer and Babylon.

Where did the names of individual stars come from?
A majority of star names used today came from the Islamic schools of astronomy established between the 8th and 14th centuries, particularly by the Moors in Spain. Many names were originally assigned to stars by Bedouin tribespeople.

Are all the stars in a constellation the same distance from us?
No. The stars in a constellation generally have no connection with one another. Chance alignments of stars have created the patterns people see in the sky.

Why do stars twinkle?
Stars appear to twinkle because we are viewing them through thick layers of moving air in the Earth's atmosphere.

Why do groups of stars continue to stay together?
All groups of stars are held together by gravitational forces.

Cabinet, by Martha Glowacki
Martha Glowacki, Starry Transit, 2004, wood, glass, brass, copper, bird carcasses, paper, pigments (detail).
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How is Starry Transit: An Installation by Martha Glowacki, organized by the Madison Museum of Contemporary Art, related to stars and constellations?
Sculptural artist Martha Glowacki created an installation at Washburn Observatory, for which she constructed models of constellations and etched images from nineteenth century celestial atlas maps. She was inspired by scientific studies revealing that night flying migratory birds use star patterns for navigation.