From: Thomas Hockey et al. (eds.). The Biographical Encyclopedia of Astronomers, Springer Reference. New York: Springer, 2007, p. 740

Courtesy of

Marwarrūdhī: Khālid ibn ʿAbd al‐Malik al‐Marwarrūdhī

Marvin Bolt

FlourishedDamascus, (Syria), 832

Along with ʿAlī ibn ʿĪsā al‐Asurlābī and a party of surveyors, Khālid ibn ʿAbd al‐Malik al‐Marwarrūdhī traveled to the Plain of Sinjār under orders of ʿAbbāsid Caliph Maʾmūn to determine the size of the Earth by making accurate measurements of one degree of latitude. Marwarrūdhī designed instruments, including an armillary and an astrolabe, for observations made in Baghdad. Following the death of Yayā ibn Abī Manūr, ʿAbbās ibn Saʿīd al‐Jawharī selected Marwarrūdhī to prepare appropriate instruments for placement at the Dayr Murrān monastery on Mount Qāsiyūn near Damascus. There, he led the yearlong series of solar and lunar observations circa 832, though he encountered considerable difficulties with the warping and expansion of the copper and iron instruments. The first of three generations of astronomers, he also took part in the project circa 843/844 in Baghdad concerning observations for determining the length of the spring season.

Selected References

Barani, Syed Hasan (1951). “Muslim Researches in Geodesy.” In Al‐Bīrūnī Commemoration Volume, A. H. 362–A. H. 1362, pp. 1–52. Calcutta: Iran Society. (Includes transcriptions and an analysis of Arabic primary sources, as well as translations.)

Kennedy, E. S. “A Survey of Islamic Astronomical, Tables.” Transactions of the American Philosophical Society, n.s., 46, pt. 2 (1956): 121–177, esp. pp. 127, 136. (Reprint, Philadelphia: American Philosophical Society, 1989.) (An important list, with excellent introduction to the topic of zījes.)

King, D. A. (2000). “Too Many Cooks … A New Account of the Earliest Geodetic Measurements.” Suhayl 1: 207–241. (Provides translated texts related to Marwarrūdhī's involvement with measuring the Earth.)

Langermann, Y. Tzvi (1985). “The Book of Bodies and Distances of Ḥabash al‐Ḥāsib.” Centaurus 28: 108–128. (A recently discovered Arabic manuscript includes contemporary records of astronomical projects initiated by Caliph Maʾmūn. With English translation and discussion.)

Sarton, George (1927). Introduction to the History of Science. Vol. 1, p. 566. Baltimore: Published for the Carnegie Institution of Washington by Williams and Wilkins.

Sayılı, Aydın (1960). The Observatory in Islam. Ankara: Turkish Historical Society. (See Chap. 2, “Al Maműn's Observatory Building Activity,” pp. 50–87, for a valuable discussion, beginning with a thorough analysis of early Islamic astronomical observations.)