Las estrellas de Nasir al-Din al-Tusi
Muhammad ibn Muhammad ibn al-Hasan al-Tūsī (Persian: محمد ابن محمد ابن حسن طوسی 18 February 1201 – 26 June 1274), better known as Nasir al-Din al-Tusi (Persian: نصیر الدین طوسی; or simply Tusi /ˈtuːsi/[4] in the West), was a Persian polymath, architect, philosopher, physician, scientist, and theologian.[5] Nasir al-Din al-Tusi was a well published author, writing on subjects of math, engineering, prose, and mysticism. Additionally, al-Tusi made several scientific advancements. In astronomy, al-Tusi created very accurate tables of planetary motion, an updated planetary model, and critiques of Ptolemaic astronomy. He also made strides in logic, mathematics but especially trigonometry, biology, and chemistry. Nasir al-Din al-Tusi left behind a great legacy as well. Some consider Tusi one of the greatest scientists of medieval Islam,[6] since he is often considered the creator of trigonometry as a mathematical discipline in its own right.[7][8][9] The Muslim scholar Ibn Khaldun (1332–1406) considered Tusi to be the greatest of the later Persian scholars.[10] There is also reason to believe that he may have influenced Copernican heliocentrism.[11][12][13][14][15][16] Nasir proposed that humans are related to animals and that some animals have a limited level of awareness while humans have a superior level of awareness amongst animals. He also framed a very basic evolutionary theory (though markedly different from modern evolutionary theory). [17]
A Treatise on the Astrolabe by Tusi, Isfahan 1505
Works:
Sayr wa-Suluk (The Voyage) - Autobiography[26]
Kitāb al-Shakl al-qattāʴ Book on the complete quadrilateral. A five-volume summary of trigonometry.
Al-Tadhkirah fi'ilm al-hay'ah – A memoir on the science of astronomy. Many commentaries were written about this work called Sharh al-Tadhkirah (A Commentary on al-Tadhkirah) - Commentaries were written by Abd al-Ali ibn Muhammad ibn al-Husayn al-Birjandi and by Nazzam Nishapuri.
Akhlaq-i Nasiri – A work on ethics.
al-Risalah al-Asturlabiyah – A Treatise on the astrolabe.
Zij-i Ilkhani (Ilkhanic Tables) – A major astronomical treatise, completed in 1272.
Sharh al-Isharat (Commentary on Avicenna's Isharat)
Awsaf al-Ashraf a short mystical-ethical work in Persian.[29]
Tajrīd al-Iʿtiqād (Summation of Belief) – A commentary on Shia doctrines.
Talkhis al-Muhassal (summary of summaries).
Maṭlūb al-muʾminīn (Desideratum of the Faithful)[20]
Aghaz u anjam - Esoteric interpretation of the Quran[21]
An example from one of his poems:
Anyone who knows, and knows that he knows, makes the steed of intelligence leap over the vault of heaven. Anyone who does not know but knows that he does not know, can bring his lame little donkey to the destination nonetheless. Anyone who does not know, and does not know that he does not know, is stuck forever in double ignorance.
During his stay in Nishapur, Tusi established a reputation as an exceptional scholar. Tusi’s prose writing, which numbers over 150 works, represent one of the largest collections by a single Islamic author. Writing in both Arabic and Persian, Nasir al-Din Tusi dealt with both religious ("Islamic") topics and non-religious or secular subjects ("the ancient sciences").[27] His works include the definitive Arabic versions of the works of Euclid, Archimedes, Ptolemy, Autolycus, and Theodosius of Bithynia.[27]
The Astronomical Observatory of Nasir al-Dīn Tusi.
The amazing Tusi couple
Astronomy Further information:
Tusi-couple
Tusi convinced Hulegu Khan to construct an observatory for establishing accurate astronomical tables for better astrological predictions. Beginning in 1259, the Rasad Khaneh observatory was constructed in Azarbaijan, south of the river Aras, and to the west of Maragheh, the capital of the Ilkhanate Empire.[30]
Based on the observations in this for the time being most advanced observatory, Tusi made very accurate tables of planetary movements as depicted in his book Zij-i ilkhani (Ilkhanic Tables). This book contains astronomical tables for calculating the positions of the planets and the names of the stars. His model for the planetary system is believed to be the most advanced of his time, and was used extensively until the development of the heliocentric model in the time of Nicolaus Copernicus. Between Ptolemy and Copernicus, he is considered by many[who?] to be one of the most eminent astronomers of his time. His famous student Shams al-Din al-Bukhari[3] was the teacher of Byzantine scholar Gregory Chioniades,[31] who had in turn trained astronomer Manuel Bryennios[32] about 1300 in Constantinople.
For his planetary models, he invented a geometrical technique called a Tusi-couple, which generates linear motion from the sum of two circular motions. He used this technique to replace Ptolemy's problematic equant[33] for many planets, but was unable to find a solution to Mercury, which was solved later by Ibn al-Shatir as well as Ali Qushji.[34] The Tusi couple was later employed in Ibn al-Shatir's geocentric model and Nicolaus Copernicus' heliocentric Copernican model.[35] He also calculated the value for the annual precession of the equinoxes and contributed to the construction and usage of some astronomical instruments including the astrolabe.
Ṭūsī criticized Ptolemy's use of observational evidence to show that the Earth was at rest, noting that such proofs were not decisive. Although it doesn't mean that he was a supporter of mobility of the earth, as he and his 16th-century commentator al-Bīrjandī, maintained that the earth's immobility could be demonstrated, only by physical principles found in natural philosophy.[36] Tusi's criticisms of Ptolemy were similar to the arguments later used by Copernicus in 1543 to defend the Earth's rotation.[37]
About the real essence of the Milky Way, Ṭūsī in his Tadhkira writes: "The Milky Way, i.e. the galaxy, is made up of a very large number of small, tightly-clustered stars, which, on account of their concentration and smallness, seem to be cloudy patches. because of this, it was likened to milk in color." [38] Three centuries later the proof of the Milky Way consisting of many stars came in 1610 when Galileo Galilei used a telescope to study the Milky Way and discovered that it is really composed of a huge number of faint stars.[39]
more in wiki: https://en.wikipedia.org/wiki/Nasir_al-Din_al-Tusi