Starry-eyed Surprise: Medieval Astronomy

Dame Aoife brings us a veritable galaxy of links this week, concerning astronomy not only as a natural science but also as a medieval navigation and timekeeping aid.

Greetings my Faithful Readers!

This week's topic comes to you courtesy of Apollonia Voss, who kindly shot an entire list of ideas my way. I thought it appropriate that I choose this one in the week that modern Astronomers announced they may have found an inhabitable planet similar to earth in a far-off galaxy (in the constellation Sagittarius). The title, of course, is a tip of the hat to Paul Oakenfold, and you might recognize the line of song lyrics from a certain bubbly diet beverage's commercial.

If you read on, you'll find out some fascinating things. For example, did you know that medieval star maps were most likely globes, and the constellations appeared backwards (such as they might appear to God)?

Read on, and learn more...



Dame Aoife Finn of Ynos Mon
m/k/a Lisbeth Herr-Gelatt
Riverouge, Endless Hills, Aethelmearc

The Astrolabe
by Gary Agranat and Dave Delligati
(Site Excerpt) One purpose of the astrolabe was observational. It could be used for finding the angle of the Sun, the Moon, the planets, or stars above the horizon or relative to the zenith. It could be used for surveying, such as for determining the heights of towers and mountains, or the depths of wells. However, other observing instruments existed before the astrolabe. It was the astrolabe's ability to compute astronomical information that made it more important.

Starry Messenger
(Site Excerpt) By drawing on the rich collection of instruments and books in the Whipple Collection, the University Library and the Wren Library, we have sought to produce a history of astronomy which focuses on the uses of astronomy and its instruments, as well as on the practitioners of astronomy.

Astronomy and Islam
(Site Excerpt) Astronomy has been called the "queen of sciences". It incorporates many disciplines such as physics, particularly optics, mathematics and celestial mechanics. Since ancient times, Muslim scientists have studied astronomy, contributing greatly to human knowledge. Yaqub ibn Tariq, al-Kwarizmi, al-Battani, al-Farghani, al-Sufi, al-Biruni, al-Tusi and Omar Khayyam are just a few of the scholars who have left a lasting mark in the annals of astronomy.

Rundetaarn: Oldest functioning observatory in Europe
(Site Excerpt) Rundetaarn (The Round Tower) was built on the initiative of King Christian IV (1588-1648) with Hans Steenwinkel the Younger as the architect. On 7 July, the foundation stone for Rundetaarn was laid. The tower was the first stage of the Trinitatis complex, which was to gather three important facilities for the scholars of the seventeenth century: an astronomical observatory, a student church and a university library.

Humboldt University: Practical Medieval Astronomy
(Site Excerpt) Why did people care about astronomy? Curiosity of course was important to some. But an overriding concern was the proper determination of when to celebrate Holy days, when to plant crops, etc. Of particularly great concern was the determination of Easter, a non trivial task. According to the Testament the Last Supper took place on a Thursday (the Passover meal), the Crucifixion on Friday, and the Resurrection the following Sunday.

Humboldt University: Medieval Astronomical and Timekeeping Instruments
(Site Excerpt) For this workshop I have brought instructions and materials for you to make two different time keeping instruments typical of the 11th-13th centuries. Before we begin the projects I will show you some instruments I have made which illustrate the operation of these instruments in terms of astronomical observations and phenomena. I will also discuss briefly some of the techniques I have used in making them, and relate how my methods compare to techniques current in the late Medieval period. You will find additional details about these instruments and techniques on my web-site.

by Lynn H. Nelson
A paper on the subject.

The Planets and Their Children
A Blockbook of Medieval Popular Astrology

by Marianne Hansen
(Site Excerpt) The influence of the planets on humans was a subject of popular interest in mid-fifteenth century Europe. Addressed in many medical and astrological manuscripts of the time, it made its mark in early printing through the appearance of blockbooks which contained depictions of each planet in anthropomorphic form together with an illustration of the pasttimes, professions, and conditions of its "children" - people influenced at birth by the planet.

Digital Mirror; Medieval manuscripts: Astronomy
(Site Excerpt) The oldest scientific manuscript in the National Library is NLW MS 735C, which contains various Latin texts on astronomy. The volume, written in Caroline minuscule, consists of two sections, the first (ff. 1-26) copied c. 1000, in the Limoges area of France, probably in the milieu of Adémar de Chabannes (989-1034), whilst the second (ff. 27-50), from a scriptorium in the same region, may be dated c. 1150.

Aligning Earth and Sky
Ancient Astronomy in the Kinki Area of Japan

By Steve Renshaw and Saori Ihara
(Site Excerpt) Unfortunately, the changing winds of history and modern urban development have obliterated many of the sites and relics of ancient astronomical activity in Japan. However, the Kinki region (which includes not only the large metropolis of Osaka but Kyoto, Nara, and the Asuka area to the south), can provide the traveler with some glimpse of a past in which astronomical observation played a central role in affairs of state as well as the day-to-day life of ordinary citizens.

Commission for the History of Ancient and Medieval Astronomy (CHAMA)
See especially the Bibliography page.

A Catalog of Medieval Astronomical Instruments
(Site Excerpt) The basic philosophy behind the preparation of the catalogue is that it is essential to hold the instrument in one's hands, to take it apart, to examine each part carefully - in short, to play with it for a while - in order to begin to understand it properly. Photographs are inadequate for this purpose, but in some cases it must suffice. One may need to examine some details with a magnifying glass, or even a microscope. The task for the unsigned and undated instruments is then to relate them to a school or a period. Again it is particularly useful, but rarely possible, to examine related instruments together.

Models and Machines in European Astronomy (13th - 15th Centuries)
by Michael H. Shank
(Site Excerpt) Between the 13th through the 15th centuries, Robertus Anglicus testifies to astronomers interest in the work of clockmakers, Guido de Marchia criticizes al-Bitruji and designs an instrument intertwined with cosmological speculations about planetary rings in a fluid heaven, and Giovanni de Dondi constructs an astrarium that he sees as vindicating epicycles and eccentrics.

The Galileo Project
(Site Excerpt) Here you can find records of the other scientists and scientific institutions of Galileo's time, as well as information about Galileo's astronomical observations and instruments. Additionally, you can access a document from the University of Bologna's Astronomical Museum about 17th century astronomical instruments...

Some Nautical Astronomical Terms in the Western Mediterranean c1300
by Alan H. Hartley
(Site Excerpt) Boötes [= the constellation and its alpha Arcturus, and sometimes the Bear(s)]
Lat. Bootes (Cicero); (med.) Boetes Artophilax (c1200 Lambert)
Port. Bootes (1572 Camões III.71; also Appleton)
1 Sp. Bootes (1272-75 Alfonso General Estoria I)
2 It. Boöte

Some Computer Programs for Research in the History of Ancient and Medieval Astronomy
By Benno van Dalen
(Site Excerpt) Below you will find links for downloading a number of computer programs for DOS-PC / Windows, which I hope may be useful in doing research on the history of ancient and medieval astronomy. I wrote these programs during my doctoral research at the Mathematical Institute of Utrecht University (Netherlands) and a postdoctoral fellowship of the Alexander von Humboldt Foundation which enabled me to work at the Institute for History of Science in Frankfurt am Main (Germany). Except for the database of parameter values occurring in Islamic astronomy, the programs are keyboard-driven DOS programs.

Star Maps
(Site Excerpt) The earliest representations of the sky were actually globes, on which the constellations were shown as though viewed from a God-like position beyond the stars; this meant that the constellation shapes were represented back to front by comparison with the way we see them from Earth. In the Museo Nazionale, Naples, is a marble statue of Atlas holding on his shoulders not the Earth but a globe of the heavens on which the constellations are depicted in this mirror-image way (see picture at right).