Abu Jafar Muhammad ibn Husayn Khazin ( fa, ابوجعفر خازن خراسانی; 900–971), also called Al-Khazin, was an
Iranian
Iranian may refer to:
* Iran, a sovereign state
* Iranian peoples, the speakers of the Iranian languages. The term Iranic peoples is also used for this term to distinguish the pan ethnic term from Iranian, used for the people of Iran
* Iranian lan ...
Muslim astronomer
An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...
and
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems.
Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change.
History
On ...
from
Khorasan. He worked on both
astronomy
Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...
and
number theory
Number theory (or arithmetic or higher arithmetic in older usage) is a branch of pure mathematics devoted primarily to the study of the integers and integer-valued functions. German mathematician Carl Friedrich Gauss (1777–1855) said, "Mat ...
.
Al-Khazin was one of the scientists brought to the court in
Ray, Iran by the ruler of the
Buyid dynasty
The Buyid dynasty ( fa, آل بویه, Āl-e Būya), also spelled Buwayhid ( ar, البويهية, Al-Buwayhiyyah), was a Shia Iranian dynasty of Daylamite origin, which mainly ruled over Iraq and central and southern Iran from 934 to 1062. Coupl ...
,
Adhad ad-Dowleh, who ruled from 949 to 983 AD. In 959/960 Khazin was required by the
Vizier
A vizier (; ar, وزير, wazīr; fa, وزیر, vazīr), or wazir, is a high-ranking political advisor or minister in the near east. The Abbasid caliphs gave the title ''wazir'' to a minister formerly called '' katib'' (secretary), who was ...
of Ray, who was appointed by ad-Dowleh, to measure the obliquity of the
ecliptic
The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic agains ...
.
One of Al-Khazin's works ''
Zij al-Safa'ih'' ("Tables of the disks of the astrolabe") was described by his successors as the best work in the field and they make many references to it. The work describes some astronomical instruments, in particular an
astrolabe fitted with plates inscribed with tables and a commentary on the use of these. A copy of this instrument was made, but it vanished in
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
at the time of
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...
. A photograph of this copy was taken and examined by D.A. King in 1980.
Al-Khazin also wrote a commentary on
Ptolemy
Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importance ...
's ''
Almagest'' in which he gives nineteen propositions relating to statements by Ptolemy. He proposed a different solar model from Ptolemy's.
References
Sources
*
PDF version
*
*
* Reviews: Seyyed Hossein Nasr (1998) in ''Isis'' 89 (1) pp
112-113 Charles Burnett (1998) in ''Bulletin of the School of Oriental and African Studies, University of London'' 61 (2) p
406
External links
*
{{DEFAULTSORT:Khazin, Abu Jafar Al
900 births
971 deaths
10th-century Iranian mathematicians
10th-century Iranian astronomers
Scholars under the Buyid dynasty