Home > Abd Al-Rahman Al Sufi

He lived at the court of Emir Adud ad-Daula in Isfahan, Persia, and worked on translating and expanding Greek astronomical works, especially the Almagest of Ptolemy. He contributed several corrections to Ptolemy's star list and did his own brightness and magnitude estimates which frequently deviated from those in Ptolemy's work. He identified the Large Magellanic Cloud, which is visible from YemenThe Republic of Yemen is a country in the Arabian Peninsula in Southwest Asia, and is a part of the Middle East, bordering the Arabian Sea, Gulf of Aden, and Red Sea, between Oman and Saudi Arabia. History Main article: History of Yemen The ancient Greek, though not from Isfafan; it was not seen by Europeans until magellan's voyage in the 16th century.

He was a major translator into Arabic of the Hellenistic astronomy that had been centred in AlexandriaLocated on the Mediterranean Sea coast, Alexandria (in Arabic, al-iskandariyyah is the chief seaport in Egypt, and that country's second largest city, and the capital of the Al Iskandariyah governate. It is located at 31°12'N, 29°15'E, 208 km (129 miles), the first to attempt to relate the GreekThe Greek language ( /Elini'k{/) is an Indo-European language which has existed from around the 14th century BC in the Cretan inscriptions called Linear B. Mycenaean Greek of this period is distinguished from later Classical or Ancient Greek of the 8th ce with the traditional ArabicArabic is a Semitic language, fairly closely related to, for instance, the Hebrew language and the Aramaic language, spoken throughout the Arab world and widely known outside it. It has been a literary language for over 1500 years, and is the liturgical l star names and constellationOrion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). A constellation is a group of stars visibly related to each other in a particular configuration. In three-dimensional space, most of the starss, which were completely unrelated and overlapped in complicated ways.

He observed that the eclipticThe ecliptic is the geometric plane that contains the orbit of the Earth. The orbits of most planets in the Solar System lie very close to it. Seen from the Earth, this is a bisecting great circle, superimposed upon the celestial sphere, which contains th plane is inclined with respect to the celestial equatorThe celestial equator is a great circle on the imaginary celestial sphere, which could be constructed by inflating the Earth's equator until it intersects with said sphere. The celestial equator is inclined by ~23. 5°, with respect to the ecliptic plane; and more accurately calculated the length of the tropical yearA tropical year is the length of time that the Sun, as viewed from the Earth, takes to return to the same position along the ecliptic (its path among the stars on the celestial sphere). The precise length of time depends on which point of the ecliptic one. He observed and described the stars, their positions, their magnitudes and their colour, setting out his results constellation by constellation. He identified the Large Magellanic Cloud, visible from Yemen, though not from Isfahan; , For each constellation, he provided two drawings, one from the outside of a celestial globe, and the other from the inside (as seen from the earth). Al Sufi also wrote about the astrolabe, finding numerous additional uses for it.

Al Sufi published his famous " Book of Fixed Stars" in 964, describing much of his work, both in textual descriptions and pictures.