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Delamarche Orrery (Paris)

An orrery, also called a planetarium, shows the choreography of planets as they dance with coordinated precision around the Sun.  Early models were geocentric (Earth-centered), including the ancient Antikythera device and large mechanical clocks.

This model was made in Paris by the Delamarche family of instrument makers.  Charles François Delamarche (1740-1817) was one of the leading orrery makers in Paris. His son Felix Delamarche (d. 1847) continued in the craft after his father’s death. 

Orreries are named after Charles Boyle (1676-1731), Earl of Orrery. Heliocentric (Sun-centered) orreries with 6 planets replicate the solar system as it was known before the discovery of Uranus in 1781 by William Herschel.  Neptune was discovered by J.G. Galle in Berlin in 1846, after its prediction by Urbain Le Verrier. 


How many planets are present in this orrery? 

Can you deduce from this information when was it made?

Galileo's World Exhibition Location

Source: History of Science Collections

Section: Observational Astronomy

Section Number: 6

Object Number: 32

Subject Area(s): Astronomy, Mathematics, Scientific Instruments

Time Period: Ancient to Renaissance

Region(s): Europe

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Exhibit Gallery OERs

Coma Berenices Learning Leaflet

Coma Berenices Learning Leaflet

Coma Berenices is the only one of the modern 88 official constellations named after a historical figure. It represents the hair of Berenice, Queen of Egypt (267 221 BCE), who reigned with Ptolemy III Euergetes. Learn more about this in this learning leaflet.


Discorso particolare intorno all'unisono

Vincenzo Musical Score

Vincenzo Galilei was among the first music theorists to advocate for a new system of tuning based on performance, instead of the mathematical principles of music set fourth by Pythagoras. Pythagorean music theory bases pitch on the mathematical proportions of dividing a string. Vincenzo's primary problem with this system is that, although it is great for the mathematician and the music theorist, it is impractical for the performer. All music based on this particular system of tuning would inevitably sound out of tune and unpleasant. In this learning leaflet learn about the tuning systems in the late-Renaissance period.


Pythagorean Solids: Five Regular Solids

Pythagorean Solids Learning Leaflet

Can you identify the five regular solids? 

Throughout history the regular solids were studied with keen interest by astronomers, mathematicians, artists, architects and philosophers. The Pythagoreans proved that there are only five regular solids: the cube, triangle, octahedron, dodecahedron, and icosahedron. 


Johann Kepler: Blueprints of the Universe

Kepler-Blueprints Learning Leaflet

Is there a mathematical basis of the universe? 

Johann Kepler's "Mystery of the Universe" is one of the brilliant illustrations in the history of astronomy. Kepler used the five regular Pythagorean solids to refute the major objections to Copernicanism. In this work he demonstrated that vast empty regions lying between the planetary spheres, which were required by Copernicus, were not wasted space. Rather, these gaps perfectly matched, within the limits of observational error, the geometry of the 5 regular Pythagorean solids. 


Astronomy & Music: Introduction to the Duochord

Duochord Learning Leaflet

Can you identify simple musical intervals? 

The ancient Pythagoreans envisioned the heavens as a musical scale, comprised of celestial spheres rotating according to harmonious music. For Robert Fludd, a seventeenth-century physician, the universe was a monochord, its physical structure unintelligible without an understanding of music. In this activity, explore the relationship between mathematics, astronomy, and music.