Abul Abbas Ahmad ibn Muhammad ibn al-Ferghani Kazir (798-861) – was an outstanding Central Asian astronomer, mathematician and geographer. Biographical information about the famous scientist almost was not saved, but, judging by his nickname, he was a native of Ferghana.
It is well known that during his average age al-Ferghani lived in Baghdad, working in the famous "House of Wisdom", which was based by ruler of al-Ma'mun. It was a sort of Academy of Sciences, where at that time from all parts of Central Asia prominent scholars and scientists were invited. For example, except of al-Ferghani a galaxy of great names who worked at the Academy at the time can continue: astronomer and mathematician al-Khorezmi, a physicist, called Yusuf ibn Iskhaq (al-Kindi), medics Abu-Resi as well as Hunayin ibn Iskhaq.
Al-Ma’mun Academy was a refuge of all branches of science, but astronomy was considered to be of particular importance here, which was a popular in the Middle Ages. Two observatories In Bagdabe were built, equipped with the best, at the time, tools, which allowed scientists to observe the stars and do math. A group of talented astronomers: Yahya bin Abu Mansur, Abdalmalik al-Merverrudi, Habash al-Mervezi as well as Ahmad al-Fergani, led by the head of the "House of Wisdom", a remarkable mathematician and astronomer - Al-Khorezmi, during long years of hard work made an incredible number of discoveries, were able to calculate the magnitude of the Earth meridian, to calculate the circumference of the Earth, to based up zijdi (Table of a starry sky) that contained the exact coordinates and a description of thousands of celestial bodies.
In the middle of the IX century, al-Ferghani moved to Cairo, where he lived until his death. There he immersed himself completely into engineering of astrolabe - an instrument for determining the location of celestial objects and the distances between them. It was exactly at that place, where his treatise on this instrument was written. A little later after that, thanks to the efforts of a scientist on the island of Raud a famous measuring device - nilometr was built that was used to calculate the abounding of the Nile and flood forecasting. It began to be used during construction of the Aswan High Dam and did not loose its relevance to the present day, being one of the attractions of the capital of Egypt.
The scientist wrote a lot of scientific work and was known throughout the whole world. Thus, in Europe he is known by the name of Alfraganus, and in the East, as Hasib.
He wrote the first works and treatises on astronomy, written in Arabic: "The book about the origins of science of astronomy," "The book of celestial movements and a set of science of the stars", "Book of the causality of the sky spheres" and many others. The best-known work of the scientist - "The Book of celestial movements and the set of science of the stars," is in point of fact a commentary on the famous Alexandrian astronomer work of Claudius Ptolemy - "Almagest". Here, Al-Ferghani, who wanted his job to be a teaching tool, provided a definition of astronomy as a science, dwelling on all key issues very detailed. Moreover, numerous astronomical calculations of his predecessor being carefully rechecked were also reflected in this book, he made appropriate changes too.
In the XII century, this work was translated into Latin and had a huge impact on the development of Western astronomy. Beginning from the XIII century, "Code of the science of stars" started its triumphal march around the whole world, being translated into almost every European language. During the long 700 years, the writings of Al-Ferghani were used by mankind as encyclopedias and scientific benefits, because as an astronomer - practitioner, the scientist made many discoveries. Thus, he scientifically proved that the shape of the earth – was sphere, mathematically claimed the existence of the shortest and longest days of the year (June 22 and December 23), showed according to observations that the sun had spots and he predicted a solar eclipse, which occurred in 832 year AD.
Astronomical calculations of Al-Ferghani were inextricably linked to his geographical research. Therefore, at the end of the treatise "The Code of the science of stars", the scientist placed a table of known geographical features, divided them into seven climatic zones from east to west and specified the exact coordinates.
Among the Geographical community his works such as "Introduction to Geography" and "Names of famous in the world countries and cities, as well as their climatic conditions” are still of a great popularity. In 1998 year, under the auspices of UNESCO 1200 anniversary of the talented scientist’s birthday was widely celebrated all around the world.