Today is Monday; 29th of the Iranian month of Bahman 1397 solar hijri; corresponding to 12th of the Islamic month of Jamadi as-Sani 1440 lunar hijri; and February 18, 2019, of the Christian Gregorian Calendar.

1118 solar years ago, on this day in 901 AD, the Sabian scholar and mathematician, Thabet Ibn Qurra al-Harrani, died. He greatly contributed to such important mathematical discoveries as the extension of the concept of number to positive real numbers, integral calculus, theorems in spherical trigonometry, analytic geometry, and non-Euclidean geometry. In astronomy he was one of the first reformers of the Ptolemaic system, writing the book “Concerning the Motion of the Eighth Sphere”. Including observations of the Sun, eight complete treatises by Thabet on astronomy have survived. In mechanics he was a founder of statics. He wrote “The Book on the Beam Balance” in which he finds the conditions for the equilibrium of a heavy beam. He was from Harran, presently under the control of Turkey although historically and culturally it is part of Mesopotamia. He belonged to the Sabian creed of star-worshippers, while some say he followed the Mandean creed that considers Prophet Yahya (John the Baptist) to be the principal figure and last messenger of God. Thabet was invited to Baghdad by the Iranian scientists, the Banu Musa brothers, and translated scientific texts from Greek and Syriac into Arabic. It is not known whether or not he became a Muslim, but his sons accepted Islam. His grandson, Ibrahim ibn Sinan, was a mathematician and astronomer who studied geometry and in particular tangents to circles for making sundials. He also made advances in the theory of integration. Thabet Ibn Qurra is said to have translated more than 130 books, and has left behind valuable compilations of his own.

818 solar years ago, on this day in 1201 AD, the famous Iranian Islamic theologian and scientist, Mohammad Ibn Hassan, known popularly as Khwaja Naseer od-Din Tusi was born in the city of Tus, near the holy city of Mashhad in Khorasan, northeastern Iran. He was an outstanding philosopher, scientist, mathematician and astronomer who made valuable contributions to the development of science and civilization. Even the Mongol invaders acknowledged his genius and Hulagu Khan, appointed him as his scientific advisor. Naseer od-Din Tusi built the famous observatory at Maraghah in 1262. It had various instruments such as a 4-meter wall quadrant made from copper and an azimuth quadrant which was his unique invention. Using accurately plotted planetary movements, he modified Ptolemy's model of the planetary system based on mechanical principles. The observatory and its library became a centre for a wide range of work in science, mathematics and philosophy. About the real essence of the Milky Way, Ṭusi in his book on astronomy “at-Tadhkirah fi Ilm al-Hayyah”, wrote three centuries before Galileo: “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 colour.”

He wrote some 80 books in both Arabic and Persian on various subjects including “Tajrid al-Eʿteqad” on theology, “Akhlaq-e Naseri” on ethics, “Sharh al-Isharaat Ibn Sina” on philosophy, and “Kitab ash-Shakl al-Qatta” on mathematics, etc. It is to be noted that a 60-km diameter lunar crater located on the southern hemisphere of the moon is named after him as "Naseereddin". A minor planet discovered by Soviet astronomer Nikolai Stepanovich Chernykh in 1979 is named after him “10269 Tusi”. Naseer od-Din Tusi died in Iraq and was laid to rest in the holy mausoleum of Imam Musa al-Kazem (AS), the 7th Infallible Successor of Prophet Mohammad (blessings of God upon him and his progeny).

725 solar years ago, on this day in 1294 AD, Kublai Khan, the fifth Great Khan of the Mongol Empire from 1260 to 1294 and the founder of the Yuan Dynasty in China died at the age of 79. As the second son of Tolui and a grandson of Chengiz Khan, he claimed the title of Khaqaan after the death of his older brother Mongke. His actual power was limited to China and Mongolia despite his victory over his younger brother Ariq Boke, which split the Mongol Empire into two more large empires, that is, the Ilkhans of Iran- Iraq-Syria, and the Golden Horde of Central Asia and Russia. Kublai Khan was the first non-Chinese Emperor who conquered all of China.

687 solar years ago, on this day in 1332 AD, Amda Seyon I, Emperor of Ethiopia began his brutal campaign in the Muslim areas of the Horn of Africa, destroying towns and cities, desecrating mosques, massacring thousands of people, stealing their livestock, and plundering their gold, silver and properties. A bigoted Christian with blind hatred of Islam, he acted as an agent of the Byzantine or Eastern Roman Empire and subjected Muslims to persecution and genocide. As a result the independent Muslim areas of the Horn of Africa were absorbed in Christian-ruled Ethiopia, where Muslims still make up over 40 percent of the population today.

647 solar years ago, on this day in 1372 AD, the Shafe’i hadith scholar, poet, and historian, Shahab od-Din Ahmad ibn Ali ibn Mohammad Ibn Hajar Asqalani, was born in Cairo. He memorized the Holy Qur'an at the age of ten and thereafter traveled to different lands to acquire knowledge and sciences. A prolific writer, he compiled some 150 books and treatises on various topics including the God-given merits of the Ahl al-Bayt of Prophet Mohammad (blessings of God upon him and his progeny). He died the age of 78.

614 solar years ago, on this day in 1405 AD, the Turco-Mongol conqueror, Amir Timur, died, while on expedition against China after conquering all the lands from the Mediterranean coast of Syria to River Ganges in India, and from the Persian Gulf in the south to Moscow in the north. He was of ferocious nature and sometimes destroyed entire cities and massacred whole populations. He seized the Chaghatay Khanate of Central Asia-Khorasan, destroyed the Golden Horde of Eurasia, defeated the Mamluk Empire of Egypt-Syria, conquered the Sultanate of Delhi and shattered the emerging Ottoman Empire, whose sultan, Bayazid I, he captured in battle and took as prisoner to his capital Samarqand. At the same time he patronized art, architecture and literature, especially the Persian language. He was buried in his capital Samarqand in what is now the Republic of Uzbekistan in the mausoleum known as Gur-e Amir. Born in Kesh, now known as Shahr-e Sabz, 80 km south of the famous Iranian city of Samarqand (presently in Uzbekistan), he had started life as leader of a small band of raiders, and during one such raid, he was shot by arrows that crippled his right leg for life; hence his epithet in Persian “Timur-e Lang” (Timur the Lame), which was corrupted by Europeans to Tamerlane. His empire was inherited by his youngest son, Shahrukh, whose mother was an Iranian and who during his long and peaceful reign did not pursue any policy of expansionism. A century after Timur’s death, his empire was no more as all his descendents vanished from the political scene, except for a great-great grandson, Zaheer od-Din Mohammad Babar, who established the Mughal Empire of the Subcontinent that ended in 1857 with the fall of Delhi to the British and the exiling to Burma of the last Timurid ruler, Bahadur Shah Zafar.

473 solar years ago, on this day in 1546 AD, German theologian and iconic figure of the Protestant Reformation in Christianity, Martin Luther, died, at the age of 63. He strongly disputed the claim of the Catholic Church that freedom from God's punishment for sin could be purchased with money. He wrote his famous “Ninety-Five Theses” in 1517. His refusal to retract all his writings at the demand of Pope Leo X in 1520 and the Holy Roman Emperor Charles V resulted in his excommunication by the pope. His translation of the Bible from Latin into the spoken language made it more accessible and led to the development of a standard version of the German language. Luther wrote that since the Israelites betrayed Prophet Jesus (AS) and continue to slander the Virgin Mary (SA), all Jewish homes should be destroyed, their synagogues burned, and their wealth confiscated.

455 solar years ago, on this day in 1564 AD, the Italian painter, sculptor, architect, and poet, Michelangelo, died at the age of 89. He created several works of art. The huge statues which he named Moses and David (not to be confused with the Prophets as he wrongly claimed), and the painting of the so-called Last Judgment are considered as his most important works.

274 solar years ago, on this day in 1745 AD, Italian physicist, Alessandro Giuseppe Antonio Anastasio Volta, who invented the electric battery in 1800, was born. His invention for the first time enabled the reliable, sustained supply of current. His voltaic pile used plates of two dissimilar metals and an electrolyte, a number of alternated zinc and silver disks, each separated with porous brine-soaked cardboard. His device opened a new door to new uses of electricity. Volta also invented the electrophorus, the condenser and the electroscope. His study of gases included the discovery of methane. The “volt”, a unit of electrical measurement, is named after him.

234 solar years ago, on this day in 1785 AD, Ja’far Khan Zand, who a week earlier on February 11 had defeated and killed Ali Murad Khan Zand to avenge his father, the 5th Zand ruler Sadeq Khan’s murder, crowned himself in Shiraz as the 7th king of the Zand Dynasty of Iran. Ja’far was an able military commander and he defeated the Qajar aspirant to the throne of Iran, Agha Mohammad Khan, in several battles. His rule ended four years later with his murder by Sayed Murad Khan Zand, who in turn was defeated and killed after only 4-months in power by his victim’s son, Lotf Ali Khan Zand. The fratricide amongst the Zands brought about the collapse of the 44-year dynasty founded by Nader Shah’s general, Karim Khan (who reigned for 29 glorious years by placing Ismail III Safavi as a figurehead), and led to establishment of the Qajar dynasty under Agha Mohammad Khan in 1794.

185 solar years ago, on this day in 1834 AD, French colonial forces, which had occupied Algeria in 1830, following the weakening of the hold of the Ottoman Empire on North Africa, were crushed by the forces of Amir Seyyed Abdul-Qader al-Jazaeri al-Hassani, who traced his descent to Imam Hasan al-Mujtaba (AS), the elder grandson and 2nd Infallible Heir of Prophet Mohammad (SAWA). A third of the French troopers were killed, and half of the remaining troops were taken captive. In the next two years he liberated nearly all of Algeria. He was later defeated through ruse and taken to France as a captive. Years later he was forced to renounce opposition to French rule in Algeria, and was allowed to settle in Syria where he died.

106 solar years ago, on this day in 1913 AD, Pedro Lascurain became President of Mexico for 45 minutes. It is the shortest term to date of any person as president of any country.

54 solar years ago, on this day in 1965 AD, Gambia gained independence from British colonial rule as the smallest country of Africa. Gambia, which is more than 90 percent Muslim, had accepted Islam during the 11th and 12th centuries, and was part of the Islamic Empire of Mali, before its occupation by the Portuguese by the end of the 15th century. Britain occupied Gambia in 1588, and for nearly four centuries looted its resources. In 1963, Britain was forced to grant self-autonomy and two year later independence. Gambia became a republic in 1970.

41 solar years ago, on this day in 1978 AD, the people of Tabriz in northwestern Iran rose against the despotic regime of the US supported Shah, on the 40th day of the martyrs of the Qom uprising. This was a historical movement which shocked the Pahlavi regime, and triggered a series of uprisings in the different cities of Iran, which ultimately resulted in the downfall of the Shah and victory of the Islamic Revolution.

40 solar years ago, on this day in 1979 AD, snow fell in the Sahara Desert in southern Algeria for the only time in recorded history.

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