Islamic Golden Age

Table of Contents

Background

Medicine in Medieval Islam

Al-Razi

Mathematics in Medieval Islam

Al-Khawrizmi

Astronomy and Astrology in Medieval Islam

Al-Biruni

Bibliography

Background

The Islamic Golden Age takes place from 750 CE until 1258 CE.  The Golden Age was a time when scientists and philosophers made strides in research to help innovate the culture.  The innovations didn’t just stop there.  Art and architecture also made numerous advancements.

Science took off during this time period.  The most well known scientist lived during this time period.  These scientists made many strides in astronomy and the way we see it today.  They would study eclipses, the rotation of planets, and would also calculate the circumference of the earth.  These scientists studied both Greek and Indian mathematics, which they used to incorporate into their own.  Al-Khwarizimi was one of the leading scientists in the study of algebra.  Following his discovers his work became a standard in Europe for centuries to follow.  His work was used in textbooks.

Possibly the most notable accomplishments made during this time was the advancements in medicine.  They had a system in place that you needed to pass an exam that tested your medical abilities before you could even begin treating a patient.  This was set up to help keep the credibility of doctors and pharmacists.  During this time it became standard to have hospitals set up for patients.  There would be a distinct area in place for trauma patients.  We can see similarities with today’s hospitals and that is thanks to these breakthroughs from this time.  Herbal medicines were used for treating patients for a variety of injuries.  These were cheap and easy to use.  Doctors had also found a cure for cataracts.  Perhaps the most common breakthrough that we can relate to today is the sweet syrups that pharmacists put in to medicine.  The reason for this is to encourage patients to take their medicine, as they tasted very poorly leading up to this.  Islam prided themselves on their knowledge of medicines.  They were producing many cures for a variety of diseases and circumstances.  Islamic scholars would take writings that were written in Greek and would translate them into Arabic.  They would use these writings to help develop their medicines.

Islam art had a variety of breakthroughs throughout the golden age.  Among the popular arts, metalwork, glass, ceramics, woodwork, and manuscript illumination became the most popular.  Art became a way for many to express themselves and their feelings.  On top of that, it is also a great way to portray their society and the way they lived.  The Qur’an put a lot of pressure on artists of this time period.  With demands such as forbidding artists from using human figures in religious art, it made it difficult to express your true feelings.  To avoid conformation, they would use a variety of shapes and patterns that livened up the drawings and would resemble Mosques.  These shapes would have written verses on them that could be found in the Qur’an.  They were then styled in a popular writing style, known as calligraphy.

Philosophy was a way for Islamic scholars to portray varies ideas to the general public.  They would translate philosophic texts from a large variety of different cultures.  This time was vital in protecting the works of Aristotle.  They were also responsible for taking ideas from China and India and would incorporate them with their own ideas.  This literature would be translated into a variety of other languages, primarily Latin.  This was used to help convert the modern European philosophy. 

Travel and the navigational sciences also rose during this time.  Originally, the majority of travel happened along rivers such as the Euphrates and the Nile.  Maps were improving and becoming much more detailed making travel easier to happen.  This made it easier for sailors to cross oceans instead of having to stick close to the shore while traveling.  They could use this easier navigation to help improve work for merchants.  Along with that, this made it more accessible to gain supplies from other countries.  During this time, distant countries became more accessible to sail to.  During the eighth century, Islam began to adapt to the use of paper from China.  Paper was simple to produce compared to the parchment that they were using previously.  Perhaps the most practical use of it was the ability to hold ink and producing copies.  Because of the innovations being made in Islam, the rest of the world was able to produce paper from linen. 

Architecture took a huge turn during this time.  This was a time that Mosques were being built almost regularly.  Perhaps one of the most famous Mosques, the Great Mosque of Kairouan, was built in 670.  The size of the Mosque was unlike anything else from this time.  It was a three-tiered square minaret along with a courtyard surrounded with prayer hall.  The Great Mosque at Cordoba was built in 785.  This was important, as this was the beginning of architecture in Northern Africa and Spain.  This mosque is most notably known for its arches located in the interior.  As time went on, they began to make innovations to their developments.  Producing structures that were extremely large, but also had a feature that were liked by many.  For example, the fortress of Granada had an open area that allowed a breeze to come through the interior space.  On the inside, there would be a variety of writings and Arabic inscriptions.  The walls would be covered with glazed tiles. 

The economy was also making vast improvements such as a trading market that became very efficient.  Along with trade, they passed along culture, religion, technology, and other various cultural improvements.  Partnerships were being formed to help generate business across the sea.  With that, there was a rise of banks to help with the differences in currency when trades and sales were being made from country to country.  This allowed for country to form alliances as well.  With this business, countries were beginning to become very wealthy.  The Islamic Empire became very rich which helped to stimulate many of their cultural and intellectual achievements. 

Golden Age

Medicine in Medieval Islam

Overview

Islamic medicine was the central part of its culture. Islamic physicians and scholars have devoted themselves into complex literature exploring to develop various theories and practices of medicine. It was initially built on tradition, specifically based on the theoretical and practical knowledge developed in Arabia. Islamic medical writing was influenced by several different medical systems, including the traditional Arabian medicine of Muhammad's time, ancient Hellenistic medicine such as Unani, ancient Indian medicine such as Ayurveda, and the ancient Iranian Medicine of the Academy of Gundishapur. The works of ancient Greek and Roman physicians Hippocrates, Dioscorides, Soranus, Celsus, and Galen also had a lasting impact on Islamic Medicine.

Muhammad ibn Zakariya al-Razi and his contribution to Islamic Medicine

Muhammad ibn Zakariya al-Razi, also known as Al-Razi (or Rhazes in Latin) was well known for his work in the field of medicine during his time. In recognition of his authority and achievements in medicine, he was given the title “Galen of Arabs” and was considered the father of Islamic medicine, “the greatest physician of the Muslim World”, as well as a respected philosopher. In addition to being a physician, he was also an encyclopedic scholar, written more than 200 books during his lifetime in which half of his books are based on medicine.

Al-Razi is known for separating the “science of physic” into two different aspects: physical and spiritual. The physical dealt with the “physiological disease” whereas spiritual deals with the spiritual self. He believes that a doctor must master both physical and spiritual knowledge of the body in order to understand the science of the body. As Al-Razi was also interested in medical ethics, he wrote a book called Ahlaq al-Tabeeb that talks about the importance of morality in medicine. He also believed that it is important for physicians to not only be experts on the field, but also be a role model to others. Based on the ideas of medical ethics, Al-Razi developed three concepts: the physician's responsibility to patients and to self, and also the patients’ responsibility to physicians.

Medical Contributions from Medieval Islam

Human Anatomy and Physiology

Ibn al-Nafis discovered the importance in the knowledge of human anatomy and physiology.

Originally, the Greek Physicians discovered the movement of blood through the human body, but how the blood flow from the right ventricle to the left ventricle of the heart, before the blood is pumped into the rest of the body was not known during their time. During the 2nd century, Galen proposed a statement describing that blood reached the left ventricle through invisible passages in the septum. On the other hand, Ibn al-Nafis, a 13th century Syrian physician, claimed Galen’s statement on the blood flow from the right ventricle to the left to be false. To prove that Galen’s statement was false, Ibn al-Nafis discovered that the septum was impenetrable and there were no signs of any invisible passages present. In addition, Ibn al-Nafis also discovered that the blood on the right ventricle was carried to the left ventricle through the way of the lungs. Through this discovery, Ibn al-Nafis was the first to describe the pulmonary circulation of the blood. Although his writings on the subject were rediscovered in the 20th century, it was William Harvey’s independent discovery that made him the first person to describe completely and in detail the pulmonary circulation and the properties of blood being pumped to the body by the heart.

According the Ancient Greeks, vision was thought be a spirit emanating from the eyes that allowed an object to be perceived. During the 11th century, an Iraqi scientist Ibn al-Haytham (also known as Al-Hazen in Latin), developed a new concept on human vision. In his approach towards human vision, he explains that the eye was an optical instrument. Based on the description on the anatomy of the eye, he developed a theory of image formation, which is explained through the refractions of light rays passing between two media of different densities.

Drugs

Aside from the development and expansion of the human anatomy, plants were also considered to be used as a remedy or medicine. Many Islamic physicians use various plants as a source of medical drugs – including Papaver somniferum Linnaeus (poppy), and Cannabis sativa Linnaeus (hemp). As poppy and hemp were not known during pre-Islamic times, hemp was first introduced into the Islamic countries in the 9th century from India, through Persia and Greek culture and medical literature. Dioscorides, a great botanist of antiquity, suggests that hemp seeds are use to “quench geniture” and its juice to alleviate earaches. Beginning in 800 and lasted for two centuries, the use of poppy was restricted to the therapeutic realm. The reason for that is because high doses of poppy often exceeded medical need which can be life-threatening if used repeatedly. In addition, Ali al-Tabari explained that the extract from poppy leaves is lethal, and that the extracts and opium are considered poisonous. Aside from the fact that poppy can be harmful if used excessively, it does provide many medical benefits such as relieve pain from attacks of gallbladder stones, fevers, indigestion, eye, head and tooth aches, pleurisy, and to induce sleep.

Surgery

Surgery was developed through the expansion of the Islamic medicine in ancient Islamic society. Surgical procedures were known to physicians due to the earlier texts that include description of the procedure. However, surgery was very uncommonly practiced by physicians due to a very low success rate, despite earlier records that provide favorable outcomes to certain operations.

Techniques

Bloodletting and Cauterization were techniques that are commonly practiced by physicians in ancient Islamic society, as a therapy to treat a wide variety of illnesses.

Cauterization is a procedure used to burn the skin or flesh of a wound in order to prevent infection and stop profuse bleeding. A simple procedure involves burning the flesh or skin of a wound using a heated metal rod. This causes the blood from the wound to clot and eventually heal the wound.

A surgical technique that involves blood removal is called bloodletting, used to treat patients of bad “humours”. There are two forms of bloodletting called wet cupping and dry cupping and both are considered helpful in treating an ill patient. Wet cupping involves making small incision in the skin in order to draw up blood by applying a heated cupping glass. Heat and suction from the glass will allow blood to rise from the surface of the skin to be drained. On the other hand, dry cupping uses the same procedure as the wet cupping but does not require incision to relieve pain, itching, and other common ailments.

Anesthesia and Antisepsis

In both modern society and medieval Islamic society, anesthetics and antisepsis were important aspects of surgery. Before anesthetics and antisepsis were known, surgery was only used on patients with dislocations, traumatic injuries that result in amputation, or other common infections. Islamic physicians attempted to prevent infections when performing surgeries on sick patients by washing patients using antiseptic properties such as wine, wine mixed with oil of roses, oil of roses alone, salt water, or vinegar water. Various herbs and resins such as frankincense, myrrh, cassia, and members of the laurel family were also used to prevent infections. In addition, the use of opium has been known since ancient times used to treat pain; other pain-killing drugs used by Islamic physicians include henbane, hemlock, soporific black nightshade, lettuce seeds. Furthermore, some of these drugs, especially opium, not only have pain-killing effects but also anesthetic effects that cause a patient to lose consciousness before the operation, as a modern day anesthetic would.

Medicine

Al-Razi

Muhammad ibn Zakaria al-Razi, better known as al-Razi, was a man of many talents and of great fame. Al-Razi was born in the Iranian city of Rayy in 865 CE, right at the beginning of the Islamic Golden Age. Over his lifetime al-Razi was well-versed and very accomplished in alchemy, music and philosophy. However his true passion and genius was in medicine.

Al-Razi studied medicine under Ali ibn Sahl Rabban al-Tabari early in his life. He was well versed in Persian, Greek and Indian medical knowledge, which aided greatly in his success. Al-Razi quickly became a practicing physician with a famous reputation. He first position was as head of the Royal Hospital in Rayy and then he moved to a similar position at Baghdad to the Muqtadari Hospital. Al-Razi also spent time as the physician to the royal court and as a teacher of medicine. Most people today consider al-Razi the father of pediatrics and a pioneer in ophthalmology.

His largest and most notable contribution to medicine was his identification and distinctions between smallpox and measles. Prior to al-Razi, physicians’ simply characterized the diseases as a general rash disease. Among his many other accomplishments, al-Razi discovered numerous compounds and chemicals. Some of the most common and well known are kerosene and sulfuric acid.

He was an incredibly prolific writer with over 200 book and articles about various fields of science. Kitab al- Mansoori is one of his most notable works; it consists of 10 volumes about Greco- Arab medicines. Al-Hawi was the largest medical encyclopedia at the time. In Kitab al- Judari wa al- Hasabah, al-Razi explained his distinctions between smallpox and measles.

For that time period, al-Razi’s methods were revolutionary in the field of medicine. Not only was he incredibly knowledgeable but he was innovative and brave. His preferred medical strategy for treating and curing patients was encouraging eating correct foods. He also stressed the influence of psychological factors on an individual’s health. No other physicians at the time were considering the diet or mental state of their patients’ during diagnosis and treatment.

Al-Razi was actually the first person to record the patients’ case histories and made clinical notes about their progress and symptoms. Originally the habit began by tracking the progression of his symptoms and diseases, but after seeing the importance it became part of a standard practice.

He also was the first to propose testing remedies on animals. Despite the many laws and regulations today that protect animals from this very act, over 2,000 years ago this extra step actually saved numerous lives. Their level of medicine was nowhere near where ours is today; so testing a remedy on an animal before a human was incredibly helpful learning experience for the physicians. 

It seems unheard of that physicians in the 7th Century CE were conducting surgeries, but al-Razi was actually an incredibly accomplished surgeon for his time. Not only was he considered an expert but he made significant strides in anesthesia. He was the first to use opium for anesthesia, and experimented with the use of alcohol in medicine.

His distinction between smallpox and measles seems to be his most praised accomplishment, but he was also among the first to use Humoralism to distinguish and diagnosis contagious diseases. Humoralism is now a discredited theory, but for that time period it was an incredibly inventive theory that helped numerous physicians identify diseases. Humoralism is based around the four basic body fluids (blood, yellow bile, black bile and phlegm), which correspond to one of the four temperaments.

Towards the end of his life al-Razi concentrated on teaching medicine. After many years of traveling around the Islamic world, al-Razi had collected many students who traveled back to Rayy to follow their teacher. Al-Raze was known as an incredibly generous and patient man. He was very charitable to the individuals he treated, rarely charging them a fee for his services and always giving them as full of a treatment as he could provide. 

In a story that only holds true to a pioneer in ophthalmology, in his final years al-Razi developed cataracts that left him blind. A man who was selling eye cream approached al-Razi with a promise that this cream would bring back his eyesight. The always quick witted al-Razi asked the man to name the layers of the eye, and the man was stumped. Al-Razi concluded by stating that no cream could ever cure his condition, especially when sold by a man who knew nothing about the eye. He died in 925 CE at the age of 60.

Al-Razi

Mathematics in Medieval Islam

During the Islamic Golden Age mathematics flourished and scholars made huge advancements, expanding on other scholars’ theories and hypotheses. Mathematics in Medieval Islam is also known as Islamic mathematics or Arabic mathematics. Islamic mathematicians expanded on Greek and Indian mathematicians, yet they also developed many of their own theorems and mathematical equations.

Mathematics even turned into an art during this time, complex geometric patterns were being used to decorate buildings. Below are a few examples of the patterns they used:

Pattern

Also during this time, the House of Wisdom was set up in Baghdad in 810, and Greek and Indian mathematical and astronomy works were being translated into Arabic. The set up of the House of Wisdom contributed to the enormous impact Islamic mathematicians made.

Islamic mathematicians have contributed greatly to the math world today. Islamic mathematicians: fully developed the decimal place-value number system, standardized the study of algebra, considered the relationship between algebra and geometry, and made improvements in plane and spherical geometry. Algebra is the part of mathematics where letters and other symbols are used to represent numbers and quantities in formulas and equations. Geometry is a division of mathematics that is concerned with the properties and relations of points, lines, surfaces, solids and other higher dimensional objects. They also made advances on the most important Greek geometrical theses of Euclid, Archimedes, and Apollonius. Euclid, Archimedes and Apollonius are three very important Greek mathematicians. Mathematicians during the Islamic Golden Age also expanded on irrational numbers, which are numbers that cannot be written as a simple fraction and the process of induction from Greek mathematicians.

One of the most important contributions from Islamic mathematicians was the expansion of algebra. Islamic mathematicians combined Indian and Babylonian material with Greek geometry to develop algebra. One of the most important mathematicians during this time contributed immensely to the expansion of algebra, his name was Muhammad Al-Khwarizmi. He was also an early director of the House of Wisdom. Al-Khwarizmi introduced the basic algebraic methods of “reduction” and “balancing” and helped create the abstract mathematical language we use today (to learn more about Al-Khwarizmi, read the next section). Another Persian mathematician Muhammad Al-Karaji expanded algebra even further.

Muhammad Al-Karaji expanded the concept of algebra by introducing the theory of algebraic calculus. Calculus is another branch of mathematics involving derivatives and integrals of functions. Al-Karaji was the first to use the method of proof by mathematical induction to prove his results. A proof by mathematical induction is done by first proving that the first statement in an infinite sequence of statements is true, and then proving that, if any statement in the sequence is true, then the next one must also be true and so on. He also used proof by mathematical induction to prove the binomial theorem. A binomial is the algebraic expression which has two terms which are operated on by addition, subtraction, multiplication and positive whole-number exponents. The binomial theorem later helped the theory of Pascal’s Triangle come about.

Binomial

Omar Khayyam is another great mathematician during this time that helped create the foundation of algebraic geometry. He generalized Indian and possibly Greek methods for extracting square and cube roots to include higher roots. He discovered that there were actually many different types of cubic equations. Khayyam did succeed in solving cubic equations but his downfall was that he could not separate the algebra from the geometry which held him back from any further advances. Yet, separating algebra from geometry ended up happening about 500 years later by Italian mathematicians.

Another successful and important mathematician during this time was Nasir Al-Din Al-Tusi. Al-Tusi is known for being one of the first to treat trigonometry as a separate branch in mathematics, differing it from astronomy. His work expanded work from earlier Greek and Indian mathematicians. He took their work about the sine function and gave one of the first descriptions of spherical trigonometry. Another one of his most known mathematical offerings was the formulation of the law of sines for plane triangles.

Mathematics was just one of the great accomplishments that emerged during the Islamic Golden Age. Islamic mathematicians expanded on theories and proofs from other countries and developed their own theories, proofs and equations that are still used today. The work that they did centuries and centuries ago has made a large impact on the mathematical world.

Al-Khawrizmi

Al-Khawrizmi early years were not recorded from birth. Very vague information about his life was known. However, he made a name for himself in the years that took over his life in Algebra. What is known is that a Persian family raised him and that his birthplace is Chorasmia. Authors tend to argue where he came from and what his name truly is. Some suggest his name is a clue to the place Khwarezm. It occupied the eastern part of Greater Iran. He was possibly from there.

Most believed it was possible that he could be of Zoroastrian religion. The Algebra indicates that he was a conservative type Muslim when it came to religion of his kind. They have documented that most of his work was recorded in 813 to 833. He was noted to be in the house of House of Wisdom in Baghdad.

It was around the twelfth century that his work was being recognized. He was known to be a mathematician, geographer, and an astronomer. The number system was well known in this era as the decimal positional number system.  The Western world finally was aware of this system because they translated his work there. This system was a method of encoding numbers. The scale that this type of mathematical equation was on was a different angle than all the others represented to the world. It became popular very quickly.  He also created a book on his findings. He called it: Book on Calculation by Completion. It represented the first systematic solution on linear and quadratic equations.

In Renaissance Europe he is considered the inventor of Algebra. The book he wrote was in 830 CE.  It was complete with examples and applications. It focused on a wide range of problems as well. The term “algebra” itself identifies the meaning of basic operation with equations.  It is also an extensive account of how to solve polynomial equations up to the second degree. It defines how to achieve fundamental methods of reduction and balancing. Many methods were defined inside the book as an example was listed as this:

  • squares equal roots (ax2 = bx)
  • squares equal number (ax2 = c)
  • roots equal number (bx = c)
  • squares and roots equal number (ax2 + bx = c)
  • squares and number equal roots (ax2 + c = bx)
  • roots and number equal squares (bx + c = ax2)

It used modern mathematical problem solving equations and the problems that occur  within the equation. His contribution to today as we know it was in many other forms;  he was recognized for as well. Much was responsible for the Indian system of numeration spreading through the Middle East.

Much of the work created needed translation. He also contributed to astrolabe. Astrolabe is an elaborate inclinometer that is used to predict the positions of the sun, moon, planets, and the stars. This may have been better known as the Sundial. The Sundial is a tool that calculates the time of day it is - by the position of the sun. As the sun moves the Sundial is positioned in one spot to identify each shadow. It was all translated into Latin. It had a great impact in the advancement of mathematics. He did get the original resource for his work from Indian sources.

His second contribution to mathematics that was also very recognized - it was arithmetic.  It survived some languages but not others, such as Arabic. It was mostly offered during the 12th century. The book created for this element of mathematics to relate was called: The Book of Addition and Subtraction according to the Hindu Calculation. His work was noted for introducing Arabic numerals.

Another great love in his life was Astronomy. He created tables of astrological data. This was in part crediting Indian Astronomical methods. His work consisted of tables that defined the movement of the sun, the moon, and movement of the planets. Most of this worked survived. It stamped a turning point in the astronomy of Islamic views.

A book on the appearance of Earth or The image of the Earth was created by him as well. It was a completed version of a Ptolemy’s Geography. It had the coordinates of 2,402 cities and other geographical places. The book consisted of latitudes and longitudes. It was used until it was not legible any longer. Several manuscripts of this consist of more work from Al-Khwarizmi.

Without contributions such as this from the past, Algebra and many other pieces of education could have been different in our modern society. People like Al-Khwarizmi paved a new way with education because of his intelligence and skill.  The fact that he implemented his work in books was the record we needed, even if his name if not entirely clear.

Al-Khawrizmi

Astronomy and Astrology in Medieval Islam

The Abbassid Dynasty was between 750 to 1258, it is also known as the Islamic Golden Age in which many intellectual and cultural achievements are contributed to the world by the Islamic culture.  ne of its great contributions is the astronomical developments.  During the middle ages, the Arabs preserved the astronomical heritage when European science was not at its best time. Since the Islamic religion requires the believers to pray 5 times day at specific position of the sun, the study of the sky became extremely important to the Muslims. 

The pre-Islamic Arabs relied on empirical observations rather than a system of mathematical astronomical study compared to the Greeks.  In 830, the first major astronomy work was Zij al-Sindh by Al-Khwarizmi. The book introduced Ptolemaic system to the Islamic science.  The movements of the sun, the moon, and the five planets known at the time were recorded in the book. The book became the foundation for study method and calculation for Muslim astronomers.  The book Kitab Fi Jawani (A compendium of the science of stars) written by Al-Farghani in 850 corrected Ptolemy and gave summary of Ptolemic cosmography.  However, the framework of Ptolemaic system of astronomy was questioned by Muslim astronomers during the period 1025-1450. Many books during this time criticized the Ptolemic mode, such as Al-Shuku ala Batlamyus, Tarik al-Aflak and al-Istidrak ala Batlamyus.  As a result, many astronomers studied and tried to resolve or come up with alternative solution to the Ptolemic astronomy.

Under the patronage of al-Mamun, observation of the Sun, moon, and planets were undertaken, solar parameters were established and the meridian degrees were measured. During the Buwayhid dynasty, extensive works in astronomy were undertaken and large scale instruments were constructed.  The first large observatory was established by Malik Shah I in Isfahan. Many astronomers collaborated and worked there, the result is the creation of the Persian Solar Calendar that is still in use in Iran today.  Hulegu Khan founded the most influential observatory during the 13th century, where astronomers gathered and made modifications to the Ptolemaic system.

Ulugh Beg

Above is the Ulugh Beg Observatory in Samarqand.

The instruments that the Muslim astronomers used had many improvements to the predecessors. The celestial globe was used to solve celestial astronomy problems. Many of the globes are still remaining today. Armillary spheres are similar in its usage but none survived through the centuries.

The astrolabes were developed as aid to find the qibla. The Islamic calendar is a lunar calendar so the astrolabe simplifies the calculation of the months and dates by removing some mathematical calculations. Though the astrolabe is not accurate in calculating the calendar, but its application is very significant in finding the position of the sun/moon, sunrise and the visibility of the moon. The first astrolabe was improved by Fazari based on what the Greeks had built. It was then perfected to find the beginning of Ramadan, hours of prayer and the direction of Mecca.  Al-Zarqall constructed an instrument that became known as the Saphea that reads the time of sun rise and is independent of the latitude of the observer; this enables the user to use it anywhere. The theory and construction sundials were also improved by the Muslims. Khwarizmi made a table to shorten the time of calculations. Quadrants were invented by the Muslims to determine time by observation the sun or stars.  The eupatorium is also invented by the Arabs to find the position of the moon, sun and planets without using a geometric model.

Islamic Astroglobe

Above is an Islamic astroglobe.

Besides the instruments, there are many notable Islamic astronomers such as Al Khawarzim in the 9th centuryi.  He is also a mathematician who invented algebra. He created the “astronomical tables of Sind and Hind” that is made of 37 chapters and 116 tables of calendric and astronomical calculations/data.  This work became the turning point in Islamic astronomy as the Muslims astronomers began to translate works of others and learning knowledge that were already discovered.

Al-Farghani is another Islamic astronomer employed by the Abbasid caliph al-Ma‘mūm. He accepted the Ptolemaic model of the universe and helped spreading it to the Islamic world and Europe. He wrote many books on astrolabe, sundials and astronomical tables. The book Jawami has 30 chapters that covered various aspects of astronomy, such as the differences between Greek, roman, Russian, Egyptian and Arab calendars, Ptolemaic astronomy, inclination of the elliptic, circumference/diameter of the earth, the motion of the planets and the stars etc. His works were translated into Latin in the 12th century and made an impact on Western science.

Al-Khujandi is a Persian astronomer and mathematician in the 10th century who built a big mural sextant in the observatory near Tehran. He used it to observe a series of meridian transit of the sun. The purpose is to find the Earth’s axial tilt. He obtained 23° 32' 19" for earths tilt, not far from 23° 34' as we know today.

Al- Sufi is one of the famous 9 Muslim astronomers who wrote the “Book of Fixed Stars” in 964. The book contains texts and illustrations of constellations and their component stars, such as the one show in Figure 3. He also identified the large Magellanic Cloud and observations of the Andromeda Galaxy, which is the first galaxy other than Milky Way to be observed from earth. He made many other observations of celestial constellations and recorded them in his book. Each constellation has two drawings, one from inside the celestial globe and one from outside.

Ursa Minor

Above is a page of the Ursa Minor from the book of fixed stars.

The Islamic astronomers made major improvements on the knowledge and tools from the Greeks. Their religion obligation pushed the advancement for more accurate and precise in celestial studies. Many astronomical instruments that were already invented were perfected by the Arabs. During the Islamic Golden Age, several key Muslim astronomers reordered their findings and calculations that not only became the base for future findings, but also made a big impact on the rest of the world.

Al-Biruni

Galileo, Ptolemy, and the other scientists from Renaissance are well known as the major contributors to Astronomy. But, long before the researches done by them, there was a great Muslim scholar in Islamic Golden Age period, which is Abu Raihan Mohammed Ibn Ahmad Al-Biruni who was the first scholar who make experiments related to astronomy. Astronomy field has been discovered by Muslim thousand years ago. After the advent of Islam, Muslims needed to determine the time of the prayers, the prayer direction, the correct orientation of the mosque, the fasting month and the other important thing for religious obligation.  These calculation lead to progress in astronomy in which Muslim has to predict time based on the motion and the movements of the sun, the moon and the stars.

Abu al-Rayhan Muhammad ibn Ahmad al-Biruni or famously known as al-Biruni was a Muslim astronomer, mathematician, ethnographist, anthropologist, historian, and geographer.  Al Biruni who was born on September 4th, 773 CE is regarded as one of the greatest scholars of the medieval Islamic era. By the age of 20, he had written several acclaimed scientific papers. He also wrote over a hundred books and treatises on varied subjects such as mathematics, geometry, geography, astronomy, astrology, the density of minerals and history. It is believed that 65 percent of the books written by al Biruni were devoted to astronomy, mathematics, and related subjects like math­ematical geography.

Some of the famous books and treatises written by Al-Biruni are Maqālīd ʿilm al-hayʾah (“Keys to Astronomy”),  Kitab-al- Hind (History and Geography of India), al-Qanun al-Masudi (Astronomy, Trigonometry), al-Athar al-Baqia (Ancient History and Geography), Kitab al-Saydanah (Pharmacology) and Kitab al-Jawahir (Precious Stones), Ifrād al-maqāl fī amr al-ilāl(The Exhaustive Treatise on Shadows, and al-Tafhim-li-Awail Sina'at al-Tanjim which gives a summary of mathematics and astronomy. Al-Biruni wrote about two hundred books and made few instruments for astronomy.

He also produced a major work on astronomy, known as the al-Qanun al-Masudi dedicated to Mahmud's son, Ma'sud. It is said that Ma'sud rewarded him with an elephant-load of silver for the book but that al-Biruni returned it to the Treasury. In this book, he regards heliocentric and geocentric hypotheses as mathematically equivalent but heliocentrism as physically impossible yet approves of the theory that the earth rotates on its axis. He utilizes his observational data to disprove Ptolemy's immobile solar apogee. More recently, Biruni's eclipse data was used by Dunthorne in 1749 to help determine the acceleration of the moon and his observational data has entered the larger astronomical historical record and is still used today in geophysics and astronomy. Ma'sud granted al-Biruni a pension that enabled him to devote the rest of his life to his scientific studies and his literary work.

Phases of the Moon

Above is an illustration from al-Biruni's astronomical works, explains the different phases of the moon.

The techniques of measuring the earth and distances on it using triangulation have been introduced by al-Biruni. He found the radius of the earth to be 6339.6 km, a value not obtained in the West until the 16th century. Al-Qanun al-Masudi contains a table giving the coordinates of six hundred places, almost all of which he had direct knowledge. Not all of them were measured by al-Biruni himself because some of it were being taken from a similar table given by al-Khwarizmi.

In his book Istīʿāb al-wujūh al-mumkinah fī anʿat al-asurlāb (“Exhaustive Book on Astrolabes), he discusses the possibility of Earth’s motion, as a consequence of a particular case of one astrolabe projection, only to dismiss it quickly as philosophical speculation that should not preoccupy the practical astronomer and mathematician. The rest of the book details all the various projections of astrolabe parts, mainly start projections that al-Biruni was familiar with or could imagine.

In another well-known book al-Athar al-Baqia, he has attempted a connected account of ancient history of nations and the related geographical knowledge. In this book, he has discussed the rotation of the earth and has given correct values of latitudes and longitudes of various places. He has also made considerable contribution to several aspects of physical and economic geography in this book. At that time, people believed that earth was in the center and the planets, starts, and sun revolved around it. All these books and researches showed that al-Biruni clearly knew that 600 years before Galileo, the earth rotates on its axis daily and moves yearly around the sun. And for the first time in history, he made a scientific explanation of why the sun never sets in the North or South Pole.

The astronomy works done by al-Biruni are mostly realted to Mathematic and Geography. In his mathematical geography masterpiece, which is Tadid nihāyāt al-amākin li-taṣḥī masāfāt al-masākin (“Determination of the Coordinates of Places for the Correction of Distances Between Cities”), he detailed about all that one needed to know about determining longitudes and latitudes on land. He capped that particular discussion with a solution to the rather sophisticated spherical trigonometric problem of determining the direction of Mecca along the local horizon at Ghazna. Determining the direction of Mecca is a religious requirement for the performance of the ordained five daily prayers in Islam.

Besides astronomy, al-Biruni also made other scientific contributions including finding the accurate densities of 18 different rocks, the mathematical formula of finding exactly when a season begins and ends, and seven different methods to find north and south. He also made a method for the trisection of an angle and other problems that cannot be solved with a ruler and a compass. Furthermore, he also proved that when the speed of sound is compared to the speed of light, the speed of light is very fast, He also explained the working of natural springs and artesian wells by the hydrostatic principle of communicating vessels. He observed that flowers have 3,4,5,6 or 8 petals, but never 7 or 9. He raised questions about the formation of mountains and explained the existence there of fossils by positing that Earth was once underwater.

Al-Biruni died in 1048 CE at the age of 75 after spending 40 years in gathering knowledge and making his own contributions to it. He has been considered as one of the greatest Muslim scholars through the Islamic Golden Age period.

Al-Biruni

Bibliography

"Abu Arrayhan Muhammad Ibn Ahmad Al-Biruni." Al-Biruni Biography. Web. 11 Apr. 2012. <http://www-history.mcs.st-andrews.ac.uk/Biographies/Al-Biruni.html>.

"Abu Bakr Mohammad Ibn Zakariya Al-Razi." Crystalinks Home Page. Web. 11 Apr. 2012. <http://www.crystalinks.com/al-Razi.html>.

"ABU RAIHAN AL-BIRUNI." Muslim Scientist and Thinkers. Web. 11 Apr. 2012. <http://wzzz.tripod.com/BIRUNI.html>.

"Al-Biruni." Albalagh Home Page. Web. 11 Apr. 2012. <http://www.albalagh.net/kids/history/biruni.shtml>.

"Ancient Arab Astronomy." Web. 11 Apr. 2012. <http://enhg4.4t.com/b/b33/33_10.htm>.

"Constellations." Web. 11 Apr. 2012. <http://www.ianridpath.com/startales/alsufi.htm>.

"An Islamic Astrolabe." Starry Messenger: The Islamic Astrolabe. Web. 11 Apr. 2012. <http://www.hps.cam.ac.uk/starry/isaslabe.html>.

"Islamic Mathematics." The Story of Mathematics. Web. 11 Apr. 2012. <http://www.storyofmathematics.com/islamic.html>.

"Mathematics in Medieval Islam." Wikipedia. Wikimedia Foundation, 04 Sept. 2012. Web. 11 Apr. 2012. <http://en.wikipedia.org/wiki/Mathematics_in_medieval_Islam>.

Merriam-Webster. Merriam-Webster. Web. 11 Apr. 2012. <http://www.merriam-webster.com/>.

"MOHAMMAD IBN ZAKARIYA AL-RAZI." Muslim Scientist and Thinkers. Web. 11 Apr. 2012. <http://wzzz.tripod.com/RAZI.html>.

Morony,Michael G. “Iraq After the Muslim Conquest.” Published: 1984

"MuslimVillage.com." MuslimVillage.com. Web. 11 Apr. 2012. <http://muslimvillage.com/>.

Plant, David. "AL-BIRUNI and Arabic Astrology." Skyscript: Deborah Houlding's Astrology Pages. Web. 11 Apr. 2012. <http://www.skyscript.co.uk/albiruni.html>.

Rosen. “Toomer 1990.” Published: 1831

Saliba, George. "Al-Biruni (Persian Scholar and Scientist)." Encyclopedia Britannica Online. Encyclopedia Britannica. Web. 11 Apr. 2012. <http://www.britannica.com/EBchecked/topic/66790/al-Biruni>.

"Scholars of Renown." Web. 11 Apr. 2012. <http://www.islamicvoice.com/February2007/ScholarsofRenown/>.

"Science Museum. Brought to Life: Exploring the History of Medicine." Abu Bakr Mohammad Ibn Zakariya Al-Razi. Web. 11 Apr. 2012. <http://www.sciencemuseum.org.uk/broughttolife/people/alrazi.aspx>.

Warnock, Christopher. "Islamic Astrology and Astronomy of Al-Biruni." Renaissance Astrology. Web. 11 Apr. 2012. <http://www.renaissanceastrology.com/albiruni.html>.