Zoomorphic Retes

Good ol' M-26.  An astrolabe in the Adler's collection dating from the 14th century.  With a delightful zoomorphic rete.

Books on Astrolabes

Martin Brunold, Der Messing-Himmel. Eine Anleitung zum Astrolabium..
Institut l'homme et le temps, La Chaux-de-Fonds, 2001. ISBN 2-940088-11-X.
Introduction of the astrolabe in medieval Europe about 1000 AD. Gerbert of Aurillac (Pope Silvester II), Abbo of Fleury, Lupitus of Barcelona, Notker (Labeo) of St. Gall and Hermann the Lame of Reichenau debate the new instrument in a fictive meeting at Rome. 155 pages, 31 tables. (German).

Ernst Zinner, Astronomische Instrumente des 11. bis 18. Jahrhunderts.
C. H. Beck, München, 1957.
History of astronomical instruments. List of instrument-maker and their works and books. Timetable, bibliography. 670 pages, 80 tables. (German).

Emmanuel Poulle, Un constructeur d'instruments astronomiques au XVe siècle, Jean Fusoris.
Honoré Champion Paris 1963 (out of print).
Monography of the famous french astrolabe-maker Jean Fusoris (ca. 1365 - 1436). 208 pages. (French).

Robert T. Gunther, Astrolabes of the World.
Holland Press, London 1976 (out of print). First edition 1932.
Description of about 330 instruments, most with illustrations. Texts of Morley (engl.), Philopon (engl.), Sebokt (engl.), Bate (lat.), Hermannus contractus (lat.), Tanner (engl.). Bibliography and index. 609 pages.

Henri Michel, Traité de l'Astrolabe.
Brieux, Paris 1976 (out of print).
Detailed handbook on the astrolabe. List of astrolabists, 24 tables. 200 pages. (French).

Franz Adrian Dreier, Winkelmessinstrumente.
Kunstgewerbemuseum Berlin 1979.
catalöogue of an exhibition. Astronomy, surveying, nautic. Timetable (1436 - 1802), glossar, bibliography. 168 pages. (German).

The Planispheric Astrolabe.
National Maritime Museum, Greenwich 1982, ISBN 0-950176-45-7.
Description and use of the classical and universal astrolabe, mariners astrolabe. Instruments of the Museum. 56 pages.

Harold N. Saunders, All the Astrolabes..
Senecio, Oxford/England 1984, ISBN 0-906831-04-0.
Introduction, facts and functions, the ordinary astrolabe, problems for an ordinary astrolabe, the universal astrolabe, problems for universal astrolabes, appendices, practical hints. 102 pages.

Sharon Gibbs, George Saliba, Planispheric Astrolabes from the National Museum of American History..
Smithonian, Washington 1984.
Description of the classical astrolabe and its history. Catalogue of instruments (46 arabian, 6 western astrolabes), star-names, stereographic projection, bibliography, index. 231 pages.

Anthony J. Turner, The Time Museum, Astrolabes (Vol. 1, Part 1). 
Time Museum, Rockford/Illinois 1985, ISBN 0-912947-02-0.
Catalogue of 21 astrolabes(11 arabian, 4 indian, 6 european instruments), 4 universal-astrolabes, sun-dials and quadrants. Glossar, bibliography and index. 268 pages.

Anthony J. Turner, Early Scientific Instruments.
Sotheby's, London 1987, ISBN 0-856673-19-6.
Introduction to european scientific instruments 1400 - 1800. 10 pages with astrolabes and other astronomical instruments. 320 pages.

Arno Borst, Astrolab und Klosterreform an der Jahrtausendwende.
Carl Winter Universitätsverlag, Heidelberg 1989, ISBN 3-533041-46-8.
Introdoction of the astrolabe in medieval Europe, 10th/11th century. Hermann the Lame, Monastery Reichenau. 141 pages. (German).

James E. Morrison. The Astrolabe.
Janus, Rehoboth Beach, 2007, ISBN 978-0-93920-30-1.
Very usefull and detailed manual about the astrolabe and related instruments. 438 pages.

Johannes Hügin. Das Astrolabium und die Uhr.
Kempter KG, Ulm 1978. ISBN 3-921348-23-4.
Introduction to the astrolabe, in German. 168 pages. (German).

Roderick and Marjorie Webster, Western Astrolabes.
Katalog Adler Planetarium, Chicago 1998, ISBN 1-891220-01-2.
Detailed instroduction and catalogue with 35 astrolabes and 10 quadrants. Appendix with star-list, bibliography and index. 179 pages.

Raymond D'Hollander. L'Astrolabe, histoire, théorie et pratique.
Institut océanographique, Paris 1999, ISBN 2-903581-19-3.
Detailed standard-work. 383 pages. (French).

Emmanuel Poulle, Les Instruments Astronomiques du Moyen Age.
Astrolabica 3, Brieux, Paris 1983, ISBN 2-900347-10-6.
Some medieval astronomical instruments.44 pages. (French).

Burkhard Stautz, Die Astrolabiensammlungen des Deutschen Museums und des Bayerischen Nationalmuseums.
Oldebourg, München 1999, ISBN 3-486-26479-6.
Introduction and catalogue. 425 Seiten. (German).

Jean-Noel Trady, Astrolabes, Cartes du Ciel.
Edisud, Aix-en-Provence, 1999, ISBN 2-7449-0078-8.
Construction and use of the Astrolabe. 143 pages. (French).

Alan Stimson, The Mariner's Astrolabe.
H & S Publishers, Utrecht, 1988, ISBN 90-6194-017-6.
Description of all known Mariner's Astrolabes. 190 pages.

Geoffrey Chaucer, A Treatise on the Astrolabe (1391).
Editor Walter W. Skeat, London 1872, Reprint Meridian Publishing Co., Amsterdam 1987. Astrolabe-Text of the famous poet, for "Little Lowys my sone" (Bred and milk for childeren). 119 pages.

Robert Gunther, Chaucer and Messahalla on the Astrolabe. 
Oxford, University Press, 1929.
The Astrolabe-texts of "Messahalla" and Chaucer, with facsimile of the Chaucer manuscript. 235 pages.

Edgar Laird and Robert Fischer, Pelerin de Prusse on the Astrolabe.
Binghampton, New York, 1995, ISBN 0-86698-132-2.
Medieval french astrolabe-text (1362) with english translation, Introduction. 114 pages.

Alessandro Gunella and John Lamprey, Stoeffler's Elucidatio.
John Lamprey, Cheyenne, Wyoming, 2007, ISBN 978-1-4243-3502-2.
English translation of the famous text of Johannes Stoeffler "Elucidatio fabricae ususque astrolabii" (1512/13). 249 pages.

Partial List of Problems an Astrolabe Can Solve

• Determine the hour and direction of the sunrise (or sunset), at a given date.
• Determine the instant where the Sun will have a given Azimuth, at a given date.
• Determine the instant where the Sun will have a given Azimuth and Altitude, without knowing the date.
• Determine the hour of rise (or set) of a star on the rete, at a given date.
• Determine the instant of culmination of a star on the rete, at a given date.
• Determine the maximum altitude of the Sun over a year for a given location.
• Determine the maximum altitude of a star at a given date, for a given location.
• Determine the hour by measuring a star altitude, for a given location, at a give date.
• Determine the right ascension and declination of a star.
• Determine the sidereal time for a given location, at a given instant.
• Determine the end of the evening twilight for a given location, at a given date.

Shout Out to Liba Taub

The curator of the Adler Planetarium’s collection of rare scientific instruments when I was there, is now at Cambridge University’s history of science museum, called the Whipple Museum. There is usually a creative activity on their website, and I recommend checking it out.

Three Problems Learned People Had With the Copernican Model

1. If the Earth actually spun on an axis (as required in a heliocentric system to explain the diurnal motion of the sky), why didn’t objects fly off the spinning Earth?
2. If the Earth was in motion around the sun, why didn’t it leave behind the birds flying in the air?
3. If the Earth were actually on an orbit around the sun, why wasn’t a parallax effect observed? That is, as illustrated in the adjacent figure, stars should appear to change their position with the respect to the other background stars as the Earth moved about its orbit, because of viewing them from a different perspective (just as viewing an object first with one eye, and then the other, causes the apparent position of the object to change with respect to the background).

The first two objections were not valid because they represent an inadequate understanding of the physics of motion that would only be corrected in the 17th century. The third objection is valid, but failed to account for what we now know to be the enormous distances to the stars.

—excerpted from class notes on the University of Tennessee’s website.

Chaucer's Treatise on the Astrolabe

The text of Chaucer's user manual for the astrolabe, written as a letter to his son, is available online at Fordham University: http://www.fordham.edu/halsall/source/chaucer-astro.asp