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The Observational Instruments of Istanbul Observatory April 2005 The Observational Instruments of Istanbul Observatory IMPORTANT NOTICE: Author: Professor Sevim Tekelfi Chief Editor: Lamaan Ball All rights, including copyright, in the content of this document are owned or controlled for these purposes by FSTC Limited. In Sub Editor: Rumeana Jahangir accessing these web pages, you agree that you may only download the content for your own personal non-commercial Production: Aasiya Alla use. You are not permitted to copy, broadcast, download, store (in any medium), transmit, show or play in public, adapt or change in any way the content of this document for any other purpose whatsoever without the prior written permission of FSTC Release Date: April 2005 Limited. Publication ID: 4080 Material may not be copied, reproduced, republished, downloaded, posted, broadcast or transmitted in any way except for your own personal non-commercial home use. Any other use Copyright: © FSTC Limited, 2005 requires the prior written permission of FSTC Limited. You agree not to adapt, alter or create a derivative work from any of the material contained in this document or use it for any other purpose other than for your personal non-commercial use. FSTC Limited has taken all reasonable care to ensure that pages published in this document and on the MuslimHeritage.com Web Site were accurate at the time of publication or last modification. Web sites are by nature experimental or constantly changing. Hence information published may be for test purposes only, may be out of date, or may be the personal opinion of the author. Readers should always verify information with the appropriate references before relying on it. The views of the authors of this document do not necessarily reflect the views of FSTC Limited. FSTC Limited takes no responsibility for the consequences of error or for any loss or damage suffered by readers of any of the information published on any pages in this document, and such information does not form any basis of a contract with readers or users of it. FSTC Limited 9 Conyngham Road, Victoria Park, Manchester, M14 5DX, United Kingdom Web: http://www.fstc.co.uk Email: [email protected] The Observational Instruments of Istanbul Observatory April 2005 THE OBSERVATIONAL INSTRUMENTS OF ISTANBUL OBSERVATORY This article was first published in the International symposium on the Observatories in Islam 19-23 September 1977 (ed. M. Dizer), Istanbul 1980, pp. 33-43. Four hundred years ago, the Istanbul Observatory was founded by Taqî al-din al-Râsid at Tophane, on the European side of the Bosporus, under the sponsorship of Sultan Murad III (1574-1595). An unknown author gives the following information about the plan of its construction in Istanbul, “Thus during the glorious days of our Great King (Murad III) with the help of the Grand-vizier (Soqullu Muhammad Pasha) the foundation of a new observatory was being organised……..” “While he (Sa'd al-din) was making the necessary arrangements [when] suddenly our Master Taqî al-din, who was the greatest scientist on earth, came to Istanbul to enter the felicitous Court of the King. When he was presented to the Emperor and received by him, was promoted and decorated with a large fief, because he was truly cognizant of sciences. Also the necessary expenses for his work were given from the Imperial treasury. In order to start the work with the help of God, [a] European Castle (Frenk Sarayi) above the great and prosperous buildings of Tophane in Istanbul, may God increase its beautiful buildings, was assigned and the activities were started. To put in verse the quality of the necessary instruments in the Imperial poetry firstly this text depending the statements of Taqî al-din, is composed and named Alât al Rasâdiya li Zîj-i Shâhin- 1 shâhîya." It is stated in other sources, on the other hand, that it was Taqî al-din who took the initiative in this matter and that he suggested to Sultan Murad III to establish an observatory. Taqî al-din wished to have an observatory founded in Istanbul and the Grand-vizier Soqullu Muhammad Pasha and Khwaja Sa'd al-din became interested in the matter and supported him. He prepared a report to present to the Sultan which explained the necessity of founding a new observatory. In this report Taqî al-din explained that the available 2 astronomical tables had grown out-dated and new tables based on fresh observations had to be compiled. In this short article I am going to dwell on only the first part, that is to say the instruments built in this institution. As a matter of fact, recent research has shown that this observatory had been one of the largest of the observatories built in the 16th century and was comparable to Tycho Brahe's Uroniborg (16th century) as well as Ulug Bey's Samarqand (15th century) and Nâsir al-din Tûsî's Maragha (13th century). 1 Sevim Tekeli, “Mechul Bir Yazarin Istanbul Rasathanesinin Aletlerinin Tasvirini Veren "Alât-i Rasadiye Li Zic-i Sehinsahiye" Adli Makalesi”. Arastirma, Vol. I, p. 91. 2 Nawîzâda ibn Yahyâ Âtâî, Dhayl al-Shaqaiq. Vol. I, 1268 H.P. 268. Publication ID: 4080 Page 2 of 13 COPYRIGHT © FSTC Limited 2005 The Observational Instruments of Istanbul Observatory April 2005 The reputation of the observatory depends on first and foremost the preciseness of its instruments, secondly on the importance of the work done in it; and then on the quality of the astronomers connected to it. The available sources that give information about the instruments constructed in this observatory are: 3 • Alât-i Rasadîya li Zîj-i Shahinshâhîya (Astronomical instruments for the Zij of Emperor). 4 • Sidra Muntahâ al afkâr of Taqî al-din 5 • Âlâ al-din al Mansûr's Poem. Generally, observational instruments in an observatory can be divided into two groups: fixed and portable. In enumerating the instruments, Taqî al-din does not say anything concerning the portable instruments. From the above mentioned documents we learn that the following instruments were built with regards to the fixed group. An armillary sphere (thât al halâk) with six rings for the measurement of latitudes and longitudes. The radius of the rings is more than 4 metres. All the rings are placed on a base called the horizon and the horizon is placed on six columns, the lower ends of which are attached to another stool like the horizon. This form of a base was generally used in 16th century Europe. Figure 1a. Armillary sphere (that al-halak) of Taqî Figure 1b. Armillary sphere (that al-halak) of Tycho 6 al-Din. Brahe 3 S. Tekeli, “Mechul Bir yazarin…..”. Arastirma, Vol. I. p. 71-122. 4 Sevim Tekeli, “Takiyuddin'in Sidret ul-Munteha'sinda Aletler Bahsi”, Belleten, Vol. 25. p. 213-38. 5 Aydin Sayili, “Alâ al-din al Mansur's Poems on the Istanbul Observatory”, Belleten, Vol. 20, 1956. 6 Source from: http://www.kb.dk/elib/lit/dan/brahe/engelsktekst/instrumentlisteframe-en.htm Publication ID: 4080 Page 3 of 13 COPYRIGHT © FSTC Limited 2005 The Observational Instruments of Istanbul Observatory April 2005 A Mural quadrant (Libna) for the observations of the declinations of the sun and the stars. It is said that 7 Taqî al-din preferred the above-mentioned quadrant instead of suds-i Fakhrî and two rings used by the previous astronomers. They are two brass quadrants with a radius of six metres, placed on a wall, erected on the meridian Figure 2a. Mural quadrant (libna) of Taqî al-Din Figure 2b. Mural quadrant (libna) of Tycho Brahe8 7 Abû Mahmûd Hâmîd ibn al Khidr al Khujandi (10th century) constructed an instrument, made of an arc of a sity degree of meridian, and called Suds al Fakhri, for the measurement of the obliquity of the ecliptic. It has a radius of about twenty meters, and surpassed all previous ones in size. This arc is placed on a wall, erected on the meridian. Sevim Tekeli, “Nasiruddin, Takiyuddin ve Tycho Brahe'nin Rasat Aletlerinin mukayesesi”. Ankara Universitesi, Dil ve Tarih-Cografya Fakultesi Dergisi, Vol. 16, No. 34, p. 319. 8 Source from: http://www.kb.dk/elib/lit/dan/brahe/engelsktekst/instrumentlisteframe-en.htm Publication ID: 4080 Page 4 of 13 COPYRIGHT © FSTC Limited 2005 The Observational Instruments of Istanbul Observatory April 2005 An azimuthal semicircle (dhât al-semt wa'l irtifa) for the measurement of the altitudes and the azimuths of the stars. This instrument is composed of a copper ring representing the horizon and a semi circle perpendicular to the horizon. Figure 3a. Azimuthal semicircle (that al-semt wa’l- Figure 3b. Azimuthal semicircle (that al-semt wa’l- irtifâ) of Taqî al-Din irtifâ) of Tycho Brahe9 9 Source from: http://www.kb.dk/elib/lit/dan/brahe/engelsktekst/instrumentlisteframe-en.htm Publication ID: 4080 Page 5 of 13 COPYRIGHT © FSTC Limited 2005 The Observational Instruments of Istanbul Observatory April 2005 Parallactic ruler or triquetrum. Generally the parallax of the moon is observed with this instrument. It is made of three long pieces of wood. The first is perpendicular to the horizon; the second is connected at the head of the first with an axis; the third which has the chord division is nailed near the base. Figure 4a. Parallactic instrument of Taqî al-Din Figure 4b. Parallactic instrument of Tycho Brahe10 10 Source from: http://www.kb.dk/elib/lit/dan/brahe/engelsktekst/instrumentlisteframe-en.htm Publication ID: 4080 Page 6 of 13 COPYRIGHT © FSTC Limited 2005 The Observational Instruments of Istanbul Observatory April 2005 The wooden quadrant (Rub). It is a quarter of a circle made of wooden rulers. The altitudes of the stars and even their distances to zenith are measured by this instrument.
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