Monday, February 14, 2011

Jagdish Chandra Bose

Born: November 30, 1858
Died: November 23, 1937
Achievements: He was the first to prove that plants too have feelings. He invented wireless telegraphy a year before Marconi patented his invention.

Jagdish Chandra Bose was an eminent Indian scientist. He was the first to prove that plants and metals too have feelings.

Jagdish Chandra Bose was born on November 30, 1858 in Mymensingh (now in Bangladesh). His father Bhagabanchandra Bose was a Deputy Magistrate. Jagadish Chandra Bose had his early education in village school in Bengal medium. In 1869, Jagadish Chandra Bose was sent to Calcutta to learn English and was educated at St.Xavier's School and College. He was a brilliant student. He passed the B.A. in physical sciences in 1879.

In 1880, Jagdishchandra Bose went to England. He studied medicine at London University, England, for a year but gave it up because of his own ill health. Within a year he moved to Cambridge to take up a scholarship to study Natural Science at Christ's College Cambridge. In 1885, he returned from abroad with a B.Sc. degree and Natural Science Tripos (a special course of study at Cambridge).

After his return Jagadish Chandra Bose, was offered lectureship at Presidency College, Calcutta on a salary half that of his English colleagues. He accepted the job but refused to draw his salary in protest. After three years the college ultimately conceded his demand and Jagdish Chandra Bose was paid full salary from the date he joined the college. As a teacher Jagdish Chandra Bose was very popular and engaged the interest of his students by making extensive use of scientific demonstrations. Many of his students at the Presidency College were destined to become famous in their own right. These included Satyendra Nath Bose and Meghnad Saha.

In 1894, Jagadish Chandra Bose decided to devote himself to pure research. He converted a small enclosure adjoining a bathroom in the Presidency College into a laboratory. He carried out experiments involving refraction, diffraction and polarization. It would not be wrong to call him as the inventor of wireless telegraphy. In 1895, a year before Guglielmo Marconi patented this invention, he had demonstrated its functioning in public.

Jagdish Chandra Bose later switched from physics to the study of metals and then plants. He fabricated a highly sensitive "coherer", the device that detects radio waves. He found that the sensitivity of the coherer decreased when it was used continuously for a long period and it regained its sensitivity when he gave the device some rest. He thus concluded that metals have feelings and memory.

Jagdish Chandra Bose showed experimentally plants too have life. He invented an instrument to record the pulse of plants and connected it to a plant. The plant, with its roots, was carefully picked up and dipped up to its stem in a vessel containing bromide, a poison. The plant's pulse beat, which the instrument recorded as a steady to-and-fro movement like the pendulum of a clock, began to grow unsteady. Soon, the spot vibrated violently and then came to a sudden stop. The plant had died because of poison.

Although Jagdish Chandra Bose did invaluable work in Science, his work was recognized in the country only when the Western world recognized its importance. He founded the Bose Institute at Calcutta, devoted mainly to the study of plants. Today, the Institute carries research on other fields too.

Jagdish Chandra Bose died on November 23, 1937

Charles Darwin

Charles Robert Darwin (12 February 1809 – 19 April 1882) was an English naturalist, who proposed and provided evidence for the scientific theory that all species have evolved over time from one or a few common ancestors, through the process of natural selection. This theory became widely accepted by the scientific community in the 1930s,and now forms the basis of modern evolutionary theory. In modified form, Darwin's theory remains a cornerstone of biology, as it provides a unifying explanation for the diversity of life.

Darwin developed his interest in natural history at Edinburgh University while studying first medicine, then theology. His five-year voyage on the Beagle established him as a geologist whose observations and theories supported Charles Lyell's uniformitarian ideas, and publication of his journal of the voyage made him famous as a popular author. Puzzled by the geographical distribution of wildlife and fossils he collected on the voyage, Darwin investigated the transmutation of species and conceived his theory of natural selection in 1838. Having seen others attacked as heretics for such ideas, he confided only in his closest friends and continued his extensive research to meet anticipated objections. In 1858, Alfred Russell Wallace sent him an essay describing a similar theory, causing the two to publish their theories early in a joint publication.

His 1859 book On the Origin of Species established evolution by common descent as the dominant scientific explanation of diversification in nature. He examined human evolution and sexual selection in The Descent of Man, and Selection in Relation to Sex, followed by The Expression of the Emotions in Man and Animals. His research on plants was published in a series of books, and in his final book, he examined earthworms and their effect on soil

Marie Curie

Marya Sklodovska was the youngest of 5 children, born in 1867, Warsaw Poland. She was brought up in a poor but well educated family. Marya excelled in her studies and won many prizes. At an early age she became committed to the ideal of Polish independence from Russia which was currently ruling Poland with an iron fist, and in particular making life difficult for intellectuals. She yearned to be able to teach fellow Polish woman who were mostly condemned to zero education.

Unusually for women at that time, Marya took an interest in Chemistry and Biology. Since opportunities in Poland for further study was limited, Marya went to Paris, where after working as a governess she was able to study at the Sorbonne, Paris. Struggling to learn in French, Marya threw herself into her studies, leading an ascetic life dedicated to studying. She went on to get a degree in Physics finish top in her school. She later got a degree in Maths, finishing second in her school year.

It was in Paris, that she met Pierre Curie, who was then chief of the laboratory at the school of Physics and Chemistry. He was a renowned Chemist, who had conducted many experiments on crystals and electronics. Pierre was smitten with the young Marya and asked her to marry him. The unromantic Marya initially refused, but, after persistence from Pierre she relented. The two would later become inseparable, until Pierre's untimely death.
Marie Curie work on Radioactivity

Marie pursued studies in radioactivity. In 1898, this led to the discovery of two new elements. One of which she named polonium after her home country.

There then followed 4 years of extensive study into the properties of radium. Using dumped uranium tailings from a nearby mine, they were very slowly, and painstakingly, able to extract a decigram of radium.

Radium was discovered to have remarkable impacts. Marie actually suffered burns from the rays. It was from this discovery of radium and its properties that the science of radiation was able to develop. Using the properties of radium to burn away diseased cells in the body. Initially radiotherapy was called 'currietherapy'

The Curries agreed to give away their secret freely; they did not wish to patent such a valuable element. The element was soon in high demand and it began industrial scale production.

For their discovery they were awarded the Davy Medal (britain) and the Nobel Prize for physics in 1903.

In 1905, Pierre was killed in a road accident, leaving Marie to look after the laboratory and her 2 children.

In 1911 she was awarded a second nobel prize in Chemistry for the discovery of actinium and further studies on radium and polonium.

The success of Marie Curie also brought considerable hostility, criticism and suspicion from a male dominated science world. She suffered from the malicious rumours and accusations that flew around.

The onset of World War I in 1914, led to Marie Curie dedicating her time to the installation of X ray machines in hospitals. Marie understood that x ray machines would easily be able to located shrapnel, enabling better treatment for soldiers. By, the end of the first world war, over a million soldiers had been examined by her X ray units.

At the end of the First world war she returned to the Institute of Radium in Paris, and also took great pride in serving the fledgling League of Nations. She also published a book - radioactivity which encompassed her great ideas on science.

Marie Curie died in 1934 from Cancer. It was an unfortunate side effect of her own groundbreaking studies into radiation which were to help so many people.

Marie Curie pushed back many frontiers in science; and at the same time set a new bar for female academic and scientific achievement.

Galileo Galilei

Galileo Galilei - Astronomer and Scientist 1564-1642

Galileo was born in Florence, Italy in 1564 to a poor but noble family.

His parents recognised their child's innate intelligence and talents and so made sacrifices to have him educated. At his father's insistence, Galileo studied the profitable career of medicine. At the University of Pisa, Galileo became fascinated in a wide range of subjects. He was also critical of many of Aristotle's teaching which had dominated education for the past 2,000 years.

Galileo was appointed to be a mathematics professor at the university of Pisa, but, his strident criticisms of Aristotle, left him isolated amongst his contempories. After 3 years of persecution, he resigned and went to the university of Padua. Here he taught maths. His entertaining lectures attracted a large following and he was able to spend the next 18 years pursuing his interests in astronomy and mechanics.

During this time, Galileo made important discoveries about gravity, inertia and also developed the forerunner of the thermometer. Galileo also worked tirelessly on the science of gnomonics (telling time by shadows) and the laws of motion.

It was in astronomy that Galileo that became famous and also courted the opposition of the Holy Roman Catholic Church.

Galileo came to the same conclusions of Copernicus that the sun was the centre of the universe and not the earth. By inventing the world's first telescope, Galileo was able to make many explorations of the universe. He found that
Saturn had a beautiful ring of clouds.
The moon was not flat but had mountains and craters.
Jupiter had many moons which revolved around Jupiter rather than directly the sun.

Thus, Galileo not only had the mathematical proofs of Copernicus, but, also new proof from the science of astronomy. However, Galileo knew that publishing these studies would bring the disapproval of the church authorities.

The Church had already started to forbid the teachings of his teachings, especially anything that supported Copernicus.

However, in 1623, a new pope, Pope Urban VIII seemed to be more liberally minded and he allowed Galileo to publish his great works on astronomy and supporting the works of Copernicus.

However, after publication, elements within the Church sought to attack Galileo's position. Thus, Galileo was arrested and imprisoned for several months. He was convicted of heresy and was forced to recant his beliefs. He spent the remaining years of his life under house arrest at Arceti.

Galileo had three children. He was especially close to one of his daughters, Polissena; she took the name of Sister Maria Celeste and entered a convent near Arceti.

Despite being censured by the church, Galileo continued to make discoveries until death overtook him in 1642. He was blind by the time he passed away.

Galileo made many important contributions to the development of science

By: Tejvan Pettinger, 28/11/2008, Oxford UK

Louis Pasteur

Louis Pasteur worked tirelessly to develop antidotes and cures to many dangerous illnesses such as anthrax and rabies. He also successfully invented a way to pasteurise milk and make it safe from Tuberculoses.

Louis Pasteur was born in Dole, eastern France. He was a conscientious and hard working student, if not exceptional. One of his professors called him 'mediocre'. He received a doctorate in 1847 and after obtaining posts at Strasbourg, Lille and Paris he spent much time researching aspects of Chemistry. One key discovery related to research on tartrate acid showing the crystals contained a mirror image of right-handed and left handed isomers.

His most important discoveries were in the field of germ study. He showed that germs required certain microorganisms to develop; using this knowledge he found that the fermentation of yeast could be delayed. Louis Pasteur then turned to practical ways of killing bacteria in liquids such as milk. His process of pasteurisation successfully killed bacteria in milk without destroying milk protein. This was a radical discovery and made drinking milk safe. The process of pasteurisation was named after him and it saved many lives.

Louis Pasteur was a great believer in hard work, never content to rest on his laurels he continued to work very hard in his laboratory to develop more cures. He said in advice to other scientists

"An individual who gets used to hard work can thereafter never live without it. Work is the foundation of everything in this world."

Louis Pasteur next created a cure for anthrax - a disease that mainly affects cattle. He found that by giving cattle a weakened form of the illness they were able to develop immunity to the illness.

This success encouraged him to develop a cure for rabies - a very common disease at the time. Using similar principles he developed a weakened strain of the disease. Testing on animals affected with rabies was successful, however he was reluctant to test on humans for fear it might not work. At one point he considered testing on himself by subjecting himself to a rabies and then trying his cure. However, before he could implement his scheme a young boy was brought to him who had been bitten 14 times by a rabid dog. His parents agreed to try the uncertain new technique. His treatment was a success and news of the treatment soon spread. Over 350 people came to Louis Pasteur for treatment. Louis and his team of scientists worked around the clock to save the people who had contracted rabies.

There was only one failure a ten year old girl Louis Pelletier. Louis knew the dies ease was too advanced when she came, but, he tried nevertheless. The girl died in his arms, with tears in his eyes, the great scientist said to her parents.

"I did so wish I could have saved your little one."

It was testament to the big heart of the famous scientist he took so much interest in his patients.

in 1888, friends and supporters funded an institute for the treatment of rabies. Louis Pasteur successfully campaigned for better research facilities for scientists. His pleas of more funding were heard by Napoleon III. Louis Pasteur argued that

"Physicists and chemists without laboratories are like soldiers without arms on the battlefield.

Louis died in 1895 aged 73. On his last day he remarked

"I should like to be younger, so as to devote myself with new ardour to the study of new diseases"

Louis Pasteur had great faith in the good nature of humans. He worked tirelessly to deliver real benefits for the treatment of infectious diseases. More than any other person, Louis Pasteur helped to increase the life expectancy of man in the late nineteenth and early twentieth Century.
Achievements of Louis Pasteur
Process of Pasteurisation making milk safe to drink
Cure for rabies
Cure for anthrax
His principles were used by later scientists such as Frankland, Valley Radot, Emile Duclaux, Descours and Holmes in developing vaccines for dies eases such as typhus, diphtheria, cholera, yellow fever and different strains of plague

Friday, February 11, 2011

Prof. Stephen Hawking

Stephen William Hawking was born on 8 January 1942 (300 years after the death of Galileo) in Oxford, England. His parents' house was in north London, but during the second world war, Oxford was considered a safer place to have babies. When he was eight, his family moved to St. Albans, a town about 20 miles north of London. At the age of eleven, Stephen went to St. Albans School and then on to University College, Oxford; his father's old college. Stephen wanted to study Mathematics, although his father would have preferred medicine. Mathematics was not available at University College, so he pursued Physics instead. After three years and not very much work, he was awarded a first class honours degree in Natural Science.

Stephen then went on to Cambridge to do research in Cosmology, there being no one working in that area in Oxford at the time. His supervisor was Denis Sciama, although he had hoped to get Fred Hoyle who was working in Cambridge. After gaining his Ph.D. he became first a Research Fellow and later on a Professorial Fellow at Gonville and Caius College. After leaving the Institute of Astronomy in 1973, Stephen came to the Department of Applied Mathematics and Theoretical Physics in 1979, and held the post of Lucasian Professor of Mathematics from 1979 until 2009. The chair was founded in 1663 with money left in the will of the Reverend Henry Lucas who had been the Member of Parliament for the University. It was first held by Isaac Barrow and then in 1669 by Isaac Newton. He is currently the Director of Research at the Centre for Theoretical Cosmology, at DAMTP in Cambridge.

Stephen Hawking has worked on the basic laws which govern the universe. With Roger Penrose he showed that Einstein's General Theory of Relativity implied space and time would have a beginning in the Big Bang and an end in black holes. These results indicated that it was necessary to unify General Relativity with Quantum Theory, the other great Scientific development of the first half of the 20th Century. One consequence of such a unification that he discovered was that black holes should not be completely black, but rather should emit radiation and eventually evaporate and disappear. Another conjecture is that the universe has no edge or boundary in imaginary time. This would imply that the way the universe began was completely determined by the laws of science.

His many publications include The Large Scale Structure of Spacetime with G F R Ellis, General Relativity: An Einstein Centenary Survey, with W Israel, and 300 Years of Gravity, with W Israel. Stephen Hawking has three popular books published; his best seller A Brief History of Time, Black Holes and Baby Universes and Other Essays, The Universe in a Nutshell, and most recently in 2010, The Grand Design.

Albert Einstein

Albert Einstein was born at Ulm, in Württemberg, Germany, on March 14, 1879. Six weeks later the family moved to Munich, where he later on began his schooling at the Luitpold Gymnasium. Later, they moved to Italy and Albert continued his education at Aarau, Switzerland and in 1896 he entered the Swiss Federal Polytechnic School in Zurich to be trained as a teacher in physics and mathematics. In 1901, the year he gained his diploma, he acquired Swiss citizenship and, as he was unable to find a teaching post, he accepted a position as technical assistant in the Swiss Patent Office. In 1905 he obtained his doctor's degree.

During his stay at the Patent Office, and in his spare time, he produced much of his remarkable work and in 1908 he was appointed Privatdozent in Berne. In 1909 he became Professor Extraordinary at Zurich, in 1911 Professor of Theoretical Physics at Prague, returning to Zurich in the following year to fill a similar post. In 1914 he was appointed Director of the Kaiser Wilhelm Physical Institute and Professor in the University of Berlin. He became a German citizen in 1914 and remained in Berlin until 1933 when he renounced his citizenship for political reasons and emigrated to America to take the position of Professor of Theoretical Physics at Princeton*. He became a United States citizen in 1940 and retired from his post in 1945.

After World War II, Einstein was a leading figure in the World Government Movement, he was offered the Presidency of the State of Israel, which he declined, and he collaborated with Dr. Chaim Weizmann in establishing the Hebrew University of Jerusalem.

Einstein always appeared to have a clear view of the problems of physics and the determination to solve them. He had a strategy of his own and was able to visualize the main stages on the way to his goal. He regarded his major achievements as mere stepping-stones for the next advance.

At the start of his scientific work, Einstein realized the inadequacies of Newtonian mechanics and his special theory of relativity stemmed from an attempt to reconcile the laws of mechanics with the laws of the electromagnetic field. He dealt with classical problems of statistical mechanics and problems in which they were merged with quantum theory: this led to an explanation of the Brownian movement of molecules. He investigated the thermal properties of light with a low radiation density and his observations laid the foundation of the photon theory of light.

In his early days in Berlin, Einstein postulated that the correct interpretation of the special theory of relativity must also furnish a theory of gravitation and in 1916 he published his paper on the general theory of relativity. During this time he also contributed to the problems of the theory of radiation and statistical mechanics.

In the 1920's, Einstein embarked on the construction of unified field theories, although he continued to work on the probabilistic interpretation of quantum theory, and he persevered with this work in America. He contributed to statistical mechanics by his development of the quantum theory of a monatomic gas and he has also accomplished valuable work in connection with atomic transition probabilities and relativistic cosmology.

After his retirement he continued to work towards the unification of the basic concepts of physics, taking the opposite approach, geometrisation, to the majority of physicists.

Einstein's researches are, of course, well chronicled and his more important works include Special Theory of Relativity (1905), Relativity (English translations, 1920 and 1950), General Theory of Relativity (1916), Investigations on Theory of Brownian Movement (1926), and The Evolution of Physics (1938). Among his non-scientific works, About Zionism (1930), Why War? (1933), My Philosophy (1934), and Out of My Later Years (1950) are perhaps the most important.

Albert Einstein received honorary doctorate degrees in science, medicine and philosophy from many European and American universities. During the 1920's he lectured in Europe, America and the Far East and he was awarded Fellowships or Memberships of all the leading scientific academies throughout the world. He gained numerous awards in recognition of his work, including the Copley Medal of the Royal Society of London in 1925, and the Franklin Medal of the Franklin Institute in 1935.

Einstein's gifts inevitably resulted in his dwelling much in intellectual solitude and, for relaxation, music played an important part in his life. He married Mileva Maric in 1903 and they had a daughter and two sons; their marriage was dissolved in 1919 and in the same year he married his cousin, Elsa Löwenthal, who died in 1936. He died on April 18, 1955 at Princeton, New Jersey.


Newton, Sir Isaac (1642-1727), English natural philosopher, generally regarded as the most original and influential theorist in the history of science. In addition to his invention of the infinitesimal calculus and a new theory of light and color, Newton transformed the structure of physical science with his three laws of motion and the law of universal gravitation. As the keystone of the scientific revolution of the 17th century, Newton's work combined the contributions of Copernicus, Kepler, Galileo, Descartes, and others into a new and powerful synthesis. Three centuries later the resulting structure - classical mechanics - continues to be a useful but no less elegant monument to his genius.
Life & Character - Isaac Newton was born prematurely on Christmas day 1642 (4 January 1643, New Style) in Woolsthorpe, a hamlet near Grantham in Lincolnshire. The posthumous son of an illiterate yeoman (also named Isaac), the fatherless infant was small enough at birth to fit 'into a quartpot.' When he was barely three years old Newton's mother, Hanna (Ayscough), placed her first born with his grandmother in order to remarry and raise a second family with Barnabas Smith, a wealthy rector from nearby North Witham. Much has been made of Newton's posthumous birth, his prolonged separation from his mother, and his unrivaled hatred of his stepfather. Until Hanna returned to Woolsthorpe in 1653 after the death of her second husband, Newton was denied his mother's attention, a possible clue to his complex character. Newton's childhood was anything but happy, and throughout his life he verged on emotional collapse, occasionally falling into violent and vindictive attacks against friend and foe alike.
With his mother's return to Woolsthorpe in 1653, Newton was taken from school to fulfill his birthright as a farmer. Happily, he failed in this calling, and returned to King's School at Grantham to prepare for entrance to Trinity College, Cambridge. Numerous anecdotes survive from this period about Newton's absent-mindedness as a fledging farmer and his lackluster performance as a student. But the turning point in Newton's life came in June 1661 when he left Woolsthorpe for Cambridge University. Here Newton entered a new world, one he could eventually call his own.
Although Cambridge was an outstanding center of learning, the spirit of the scientific revolution had yet to penetrate its ancient and somewhat ossified curriculum. Little is known of Newton's formal studies as an undergraduate, but he likely received large doses of Aristotle as well as other classical authors. And by all appearances his academic performance was undistinguished. In 1664 Isaac Barrow, Lucasian Professor of Mathematics at Cambridge, examined Newton's understanding of Euclid and found it sorely lacking. We now know that during his undergraduate years Newton was deeply engrossed in private study, that he privately mastered the works of René Descartes, Pierre Gassendi, Thomas Hobbes, and other major figures of the scientific revolution. A series of extant notebooks shows that by 1664 Newton had begun to master Descartes' Géométrie and other forms of mathematics far in advance of Euclid's Elements. Barrow, himself a gifted mathematician, had yet to appreciate Newton's genius.
In 1665 Newton took his bachelor's degree at Cambridge without honors or distinction. Since the university was closed for the next two years because of plague, Newton returned to Woolsthorpe in midyear. There, in the following 18 months, he made a series of original contributions to science. As he later recalled, 'All this was in the two plague years of 1665 and 1666, for in those days I was in my prime of age for invention, and minded mathematics and philosophy more than at any time since.' In mathematics Newton conceived his 'method of fluxions' (infinitesimal calculus), laid the foundations for his theory of light and color, and achieved significant insight into the problem of planetary motion, insights that eventually led to the publication of his Principia (1687).
In April 1667, Newton returned to Cambridge and, against stiff odds, was elected a minor fellow at Trinity. Success followed good fortune. In the next year he became a senior fellow upon taking his master of arts degree, and in 1669, before he had reached his 27th birthday, he succeeded Isaac Barrow as Lucasian Professor of Mathematics. The duties of this appointment offered Newton the opportunity to organize the results of his earlier optical researches, and in 1672, shortly after his election to the Royal Society, he communicated his first public paper, a brilliant but no less controversial study on the nature of color.
In the first of a series of bitter disputes, Newton locked horns with the society's celebrated curator of experiments, the bright but brittle Robert Hooke. The ensuing controversy, which continued until 1678, established a pattern in Newton's behavior. After an initial skirmish, he quietly retreated. Nonetheless, in 1675 Newton ventured another yet another paper, which again drew lightning, this time charged with claims that he had plagiarized from Hooke. The charges were entirely ungrounded. Twice burned, Newton withdrew.
In 1678, Newton suffered a serious emotional breakdown, and in the following year his mother died. Newton's response was to cut off contact with others and engross himself in alchemical research. These studies, once an embarrassment to Newton scholars, were not misguided musings but rigorous investigations into the hidden forces of nature. Newton's alchemical studies opened theoretical avenues not found in the mechanical philosophy, the world view that sustained his early work. While the mechanical philosophy reduced all phenomena to the impact of matter in motion, the alchemical tradition upheld the possibility of attraction and repulsion at the particulate level. Newton's later insights in celestial mechanics can be traced in part to his alchemical interests. By combining action-at-a-distance and mathematics, Newton transformed the mechanical philosophy by adding a mysterious but no less measurable quantity, gravitational force.
In 1666, as tradition has it, Newton observed the fall of an apple in his garden at Woolsthorpe, later recalling, 'In the same year I began to think of gravity extending to the orb of the Moon.' Newton's memory was not accurate. In fact, all evidence suggests that the concept of universal gravitation did not spring full-blown from Newton's head in 1666 but was nearly 20 years in gestation. Ironically, Robert Hooke helped give it life. In November 1679, Hooke initiated an exchange of letters that bore on the question of planetary motion. Although Newton hastily broke off the correspondence, Hooke's letters provided a conceptual link between central attraction and a force falling off with the square of distance. Sometime in early 1680, Newton appears to have quietly drawn his own conclusions.
Meanwhile, in the coffeehouses of London, Hooke, Edmund Halley, and Christopher Wren struggled unsuccessfully with the problem of planetary motion. Finally, in August 1684, Halley paid a legendary visit to Newton in Cambridge, hoping for an answer to his riddle:  What type of curve does a planet describe in its orbit around the sun, assuming an inverse square law of attraction? When Halley posed the question, Newton's ready response was 'an ellipse.' When asked how he knew it was an ellipse Newton replied that he had already calculated it. Although Newton had privately answered one of the riddles of the universe--and he alone possessed the mathematical ability to do so--he had characteristically misplaced the calculation. After further discussion he promised to send Halley a fresh calculation forthwith. In partial fulfillment of his promise Newton produced his De Motu of 1684. From that seed, after nearly two years of intense labor, the Philosophiae Naturalis Principia Mathematica appeared. Arguably, it is the most important book published in the history of science. But if the Principia was Newton's brainchild, Hooke and Halley were nothing less than midwives.
Although the Principia was well received, its future was cast in doubt before it appeared. Here again Hooke was center stage, this time claiming (not without justification) that his letters of 1679-1680 earned him a role in Newton's discovery. But to no effect. Newton was so furious with Hooke that he threatened to suppress Book III of the Principia altogether, finally denouncing science as 'an impertinently litigious lady.' Newton calmed down and finally consented to publication. But instead of acknowledging Hooke's contribution Newton systematically deleted every possible mention of Hooke's name. Newton's hatred for Hooke was consumptive. Indeed, Newton later withheld publication of his Opticks (1704) and virtually withdrew from the Royal Society until Hooke's death in 1703.
After publishing the Principia, Newton became more involved in public affairs. In 1689 he was elected to represent Cambridge in Parliament, and during his stay in London he became acquainted with John Locke, the famous philosopher, and Nicolas Fatio de Duillier, a brilliant young mathematician who became an intimate friend. In 1693, however, Newton suffered a severe nervous disorder, not unlike his breakdown of 1677-1678. The cause is open to interpretation: overwork; the stress of controversy; the unexplained loss of friendship with Fatio; or perhaps chronic mercury poisoning, the result of nearly three decades of alchemical research. Each factor may have played a role. We only know Locke and Samuel Pepys received strange and seemingly deranged letters that prompted concern for Newton's 'discomposure in head, or mind, or both.' Whatever the cause, shortly after his recovery Newton sought a new position in London. In 1696, with the help of Charles Montague, a fellow of Trinity and later earl of Halifax, Newton was appointed Warden and then Master of the Mint. His new position proved 'most proper,' and he left Cambridge for London without regret.
During his London years Newton enjoyed power and worldly success. His position at the Mint assured a comfortable social and economic status, and he was an active and able administrator. After the death of Hooke in 1703, Newton was elected president of the Royal Society and was annually reelected until his death. In 1704 he published his second major work, the Opticks, based largely on work completed decades before. He was knighted in 1705.
Although his creative years had passed, Newton continued to exercise a profound influence on the development of science. In effect, the Royal Society was Newton's instrument, and he played it to his personal advantage. His tenure as president has been described as tyrannical and autocratic, and his control over the lives and careers of younger disciples was all but absolute. Newton could not abide contradiction or controversy - his quarrels with Hooke provide singular examples. But in later disputes, as president of the Royal Society, Newton marshaled all the forces at his command. For example, he published Flamsteed's astronomical observations - the labor of a lifetime - without the author's permission; and in his priority dispute with Leibniz concerning the calculus, Newton enlisted younger men to fight his war of words, while behind the lines he secretly directed charge and countercharge. In the end, the actions of the Society were little more than extensions of Newton's will, and until his death he dominated the landscape of science without rival. He died in London on March 20, 1727 (March 31, New Style).

Neil Armstrong

Neil Armstrong commanded the Gemini 8 mission and became the first human to walk on the moon as commander of the Apollo 11. he was born in Wapakoneta ,ohio,on the August 5 ,1930. is an American aviator and a former astronaut, test pilot, aerospace engineer, university professor, and United States Naval Aviator. He was the first person to set foot on the Moon.

Before becoming an astronaut, Armstrong was in the United States Navy and saw action in the Korean War. After the war, he served as a test pilot at the National Advisory Committee for Aeronautics (NACA) High-Speed Flight Station, now known as the Dryden Flight Research Center, where he flew over 900 flights in a variety of aircraft. As a research pilot, Armstrong served as project pilot on the F-100 Super Sabre A and C aircraft, F-101 Voodoo, and the Lockheed F-104A Starfighter. He also flew the Bell X-1B, Bell X-5, North American X-15, F-105 Thunderchief, F-106 Delta Dart, B-47 Stratojet, KC-135 Stratotanker and Paresev. He graduated from Purdue University and the University of Southern California.

His first spaceflight was aboard Gemini 8 in 1966, for which he was the command pilot, becoming one of the first U.S. civilians to fly in space (Joseph Albert Walker was the first US civilian in space several years earlier).[1][2] On this mission, he performed the first manned docking of two spacecraft together with pilot David Scott. Armstrong's second and last spaceflight was as mission commander of the Apollo 11 moon landing mission on July 20, 1969. On this mission, Armstrong and Buzz Aldrin descended to the lunar surface and spent 2½ hours exploring while Michael Collins remained in orbit in the Command Module. Armstrong is a recipient of the Congressional Space Medal of Honor.