We take a look at important contributions made by scientists over the centuries
THE WRIGHT BROTHERS
Wilbur Wright, who lived from 1867 to 1912, and Orville Wright, who lived from 1871 to 1948, were two Americans who are generally credited with inventing and building the world's first successful airplane and making the first controlled, powered and sustained heavier-than-air human flight on December 17, 1903. The Wrights based the design of their first full-size glider (as well as the 1899 kite) on the work of their predecessors, chiefly the Chanute-Herring biplane hang glider ("double-decker” as the Wrights called it), which flew in the 1896 experiments near Chicago.
SIR CHANDRASEKHARA VENKATA RAMAN
Chandrasekhara lived from 1888 to 1970. He was an Indian physicist and Nobel Laureate in Physics and was recognised for his work on the molecular scattering of light and for the discovery the Raman Effect.
On February 28, 1928, through his experiments on the scattering of light, he discovered that when light is scattered from an atom or molecule, most photons (elementary particles) are elastically scattered, such that the scattered photons have the same energy and wavelength as the incident photons. This is called the Raman Effect. This discovery gave further proof of the quantum nature of light. In 1930 he won the Nobel Prize in Physics for this work. Raman also worked on the acoustics of musical instruments. He was the first person to investigate the harmonic nature of the sound of Indian drums
Hermann was a Romanian physicist who lived from 1894 to 1989. Hermann was inspired by Jules Verneʼs science fiction novels and at an early age he started to believe that space travel was possible. He studied rockets and wrote books on how they could be used to launch objects into space. Hermann also originated the idea of stages, where he explained that once a rocketʼs fuel is used up it should be dropped as dead weight so that it doesnʼt slow down the spaceship. Hermannʼs work led to the German rocket programme which developed the rockets used to attack London in World War II.
Linus was an American chemist who lived from 1901 to 1994. He was the first person to apply quantum mechanics to chemistry and made great progress in the field of molecular biology. Linus understood and explained how atoms bond with each other to form molecules. He was awarded two Nobel Prizes during his life, one for his work in chemistry and the other one for his efforts at stopping nuclear weapons testing.
Gerard was an American astronomer who lived from 1905 to 1973. He is considered to be the father of modern planetary science for his study of the Solar System. Gerard developed new techniques of looking at the sky and discovered the moons of Neptune and Uranus. He also found that Titan, Saturnʼs moon, had an atmosphere similar to our own. Gerard suggested that there was a belt of comet-like debris at the edge of our Solar System, a theory that was proven true 20 years after his death.
DR ABE SILVERSTEIN
Abe was born in 1908. An engineer by profession, he conducted rocketry research. He originally worked for the National Advisory Committee for Aeronautics, USA and later for NASA. He supervised the development of the Centaur programme, a rocket that used liquid hydrogen as fuel. The engines developed for the Centaur programme were later used in the upper stages of the Saturn rocket that launched the Apollo missions to the Moon.
WERNHER VON BRAUN
Wernher was a German engineer who lived from 1912 to 1977. He is considered to be the father of the space age for his work in rocketry. During the 1930s and 40s, Wernher directed Germany ʼs rocket development programme through which his team of scientists built the famous V2 rockets used against England during World War II. Thereafter he started to work for USA, where he helped to construct the powerful Saturn V rockets which launched the Apollo missions to the Moon.
Richard was an American physicist who lived from 1918 to 1988. He contributed to the field of physics by working on the atomic theory and quantum electrodynamics, which studies the behaviour of electrons. After his college education, Richard was asked to participate in the Manhattan Project (the building of the first atomic bomb). He later developed safer methods for the storage of radioactive waste and saved the lives of workers at many nuclear power plants. In 1986, Richard was appointed as a part of the committee to investigate the explosion of the space shuttle Challenger. He identified the problem as resulting from faulty equipment rather than astronaut error.
Evelyn is an American mathematician. Born in 1924, she was one of the first black women in the United States to receive a PhD in mathematics. Evelyn has made many contributions to NASAʼs space shuttle programme. She has also worked as a mathematical analyst for Space Technology Laboratories.
Carl is an American astronomer who lived from 1934 to 1996. Carl is famous for his research on the origins of life and his belief that life exists elsewhere in the universe. He became a leading figure in the search for extra-terrestrial intelligence with his involvement in the Mariner, Viking and Voyager spacecraft expeditions to Venus and the outer planets. He has made contributions to the study of planetary atmospheres, planetary surfaces and the history of the Earth.
Wangari was born in Kenya in 1940. She is the first woman from East and Central Africa to earn a PhD. Wangari has also served as a long-time professor at the University of Nairobi in Kenya. She is famous for her work to stop deforestation in Kenya and other places in Africa. Wangari also founded the Green Belt Movement in 1977 to protest against different problems caused due to deforestation. The movement not only helped to stop deforestation but also paid Kenyan women to plant trees and thus provided jobs to many. The success of the project made other African countries adopt the same means. Through this project, women have planted more than 20 million trees in Africa. Wangari was awarded the Nobel Peace Prize in 2004. She was also elected to the Kenyan Parliament in 2002 and was appointed as the Assistant Minister for Environment, Natural Resources and Wildlife.
STEPHEN JAY GOULD
Stephen was an American paleontologist who lived from 1941 to 2002. He revised Darwinʼs theory of evolution, introducing his own concept of punctuated equilibrium. This states that evolution is not a gradual process but, rather, has static periods followed by brief bursts of change. Stephen was also a professor at Harvard University and wrote many books which bring the concepts of biology and evolution to the general public.
Stephen is an English astrophysicist who was born in 1942. He is a leader in the fields of theoretical physics and cosmology. Stephen is famous for his work on black holes. His theory states that black holes are bodies of matter that are so dense that their gravitational fields trap light inside. In his early twenties, he was diagnosed with an ultimately terminal illness. Today he is confined to a wheelchair and unable to speak, though he communicates his ideas with the help of computers.
JOCELYN BELL BURNELL
Jocelyn is a British astronomer who was born in 1943. Jocelyn was a graduate student at Cambridge University when she discovered pulsars— stars which emit periodic radiowaves in 1967. Her professor, Antony Hewish, received the Nobel Prize in Physics for the discovery.
SIR TIMOTHY JOHN BERNERS-LEE
Timothy was born in 1955. He is a British engineer, computer scientist and MIT professor credited with inventing the World Wide Web, making the first proposal for it in March 1989.
On December 25, 1990, with the help of Robert Cailliau and a young student staff, he implemented the first successful communication between an HTTP client and server via the Internet. On April 15, 2004, he was named as the first recipient of Finlandʼs Millennium Technology Prize for inventing the World Wide Web. In October 2009, he was awarded an honorary doctorate by the Vrije Universiteit Amsterdam.
E GIOVANNI CASSINI
Giovanni Cassini was an Italian-French astronomer who lived from 1625 to 1712. He discovered that Saturnʼs rings are split into two parts, and the gap between them is termed as the Cassini Division. Giovanni also discovered four of Saturnʼs moons, in addition to those found by Huygens 20 years earlier. Giovanni studied hydrology and means and methods to avoid floods that plagued Europe. His greatest mistakes were rejecting the Copernican model of the Solar System and Newtonʼs theory of universal gravitation.
Isaac Newton was an English scientist and mathematician who lived from 1642 to 1727. He had one of the most brilliant minds in the world. The falling of an apple enlightened Isaac with the idea of gravity, the force that keeps us bound to the Earth and also controls the motion of planets and stars. Isaacʼs contributions to science include the universal law of gravity, the development of a new field in mathematics called calculus and his three famous laws of motion.
Edmond Halley was an English astronomer who lived from 1656 to 1742. Using historical records, his own observations and Newtonʼs universal law of gravity, Edmond reasoned that the comets which had appeared in 1456, 1531, 1607 and 1682 were the same. After studying the pattern, he then predicted the cometʼs return every 76 years. Today the comet bears his name. In addition to his work on comets, Halley studied the Earthʼs weather and magnetic field and the oceanʼs tides.
Benjamin Franklin was an American scientist and statesman who lived from 1706 to 1790. During this age, when little was known about electricity, Benjamin carried out many experiments to learn of its dangers and possible uses. His famous kite experiment led him to invent the lightning rod, which protects buildings from lightning damage. His other inventions included bifocals, glasses that let you see both far and near, and a stove which heats houses more safely than a fi replace. He also worked on a peace treaty between England, France and USA, which ended the American Revolution.
NICOLE-REINE ETABLE DE LA BRIERE HORTENSE LEPAUTE
Nicole-Reine Etable de la Briere Hortense Lepaute was a French astronomer who lived from 1723 to 1788. In 1762, she calculated the exact time of a solar eclipse that was to occur in 1764. She wrote an article (published in Connaissance des Temps) about this that gave a map of the eclipseʼs extent in 15-minute intervals across Europe. Nicole also made predictions for the return of Halleyʼs Comet in 1759. She discovered how the gravitational effect of the planets would influence the cometʼs path.
William Herschel was an astronomer who lived from 1738 to 1822. He was born in Germany and lived in England. He built high magnification telescopes that let him observe the sky with greater detail. Herschel discovered the planet Uranus and advanced our understanding of nebulae, the hazy clouds that surround dying stars. He also discovered stellar astronomy, the study of the region beyond our own Solar System. Our modern sense of a galaxyʼs shape is very similar to what William had proposed hundreds of years earlier.
Friedrich Mohs was a German scientist who studied minerals. He lived from 1773 to 1839. He moved to Austria in 1801 where he found a job identifying minerals. He used physical characteristics of the minerals to decide what they were. One of the characteristics he used to identify minerals with was hardness. He knew that some of the minerals could scratch others and that if a mineral could make a scratch on another, it must be harder than the mineral that was scratched. He found that all minerals could scratch the mineral talc. He also found that diamonds were so hard that no other minerals could scratch them. About a decade later, Friedrich created a scale from one to 10 to describe mineral hardness. He gave harder minerals larger numbers and softer minerals smaller numbers. Talc, the softest mineral, he assigned to one, the smallest number on the scale. Diamond, the hardest mineral, he assigned to 10, the largest number on the scale. This scale has been named Mohs Hardness Scale and is used by geologists even today.
Christian Doppler was an Austrian mathematician who lived from 1803 to 1853. He is known for the principle of the ʻcoloured light of double starsʼ which he proposed in 1842. This principle is now known as the Doppler Effect. He hypothesised that the pitch of a sound would change if the source of the sound was moving. Christianʼs hypothesis was tested by Buys Ballot in 1845. He used two sets of trumpeters, one set stationary at a train station and one set moving on an open train car. Both sets of musicians had perfect pitch and held the same note. As the train passed the station, it was obvious that the frequency of the two notes didnʼt match, even though the musicians were playing the same note. This proved Christianʼs hypothesis. Later, a scientist named Fizeau generalised Christianʼs work by applying Christianʼs theory not only to sound but also to light.
Charles Darwin was an English naturalist who lived from 1809 to 1882. He laid the foundations for the modern science of biology and changed how other scientists understood the appearance of life on Earth. In 1859, after 30 years of study and travel, Charles published a book called ʻThe Origin of Species by Means of Natural Selectionʼ, which started a scientific revolution. It showed that life on Earth is constantly changing and only the fittest organisms could survive.
Ada Byron, Countess of Lovelace, was a British mathematician who lived from 1815 to 1852. She had a major influence on computer programming. Computer programming is essential for building space shuttles and satellites and in analyzing scientific data. Ada published ʻSketch of the Analytical Engineʼ which discussed Charles Babbageʼs analytical engine (later to be known as the first computer). Her work was based on the writings of the Italian mathematician Luigi Menabrea and meetings with Babbage himself. Ada designed the ʻpunch-cardʼ programme, which gave instructions to a computer. She also created the computer law known as GIGO (Garbage In, Garbage Out). The law states that a computer can use only what is put into it. In other words, a computer cannot have a mind of its own. Due to her pioneering efforts in computer science, the US Department of Defense named a computer programming language (ADA) after her in 1977.
Maria Mitchell was an American astronomer who lived from 1818 to 1889. She was the first female professor of astronomy in the United States. In 1847, Maria discovered a comet and was awarded a gold medal from the King of Denmark. She became the first woman to be appointed to the Academy of Arts and Sciences in 1848. In 1853, she received the first advanced degree given to a woman from Indiana Hanover College. Maria was elected president of the American Association for the Advancement of Women in 1875. After her death, a crater on the moon was named after her.
Louis Pasteur was a French chemist who lived from 1822 to 1895. He discovered that fermentation, the process used to make beer and wine, is carried out by tiny animals. Louis termed these microorganisms as ʻgermsʼ and learnt that they are also responsible for spreading contagious diseases. He thus solved the mystery behind rabies and created vaccines for this and other deadly illnesses, saving many lives. Louis also dispelled the myth of spontaneous generation, proving that all life comes from pre-existing life.
JAMES CLERK MAXWELL
James Clerk Maxwell was a Scottish physicist who lived from 1831 to 1879. He studied Saturnʼs rings and suggested that they were composed of solid particles. This theory was confirmed 100 years later by the Voyager 1 space probe. James is also famous for his equations related to electricity and magnetism. His revolutionary work lead to the development of quantum physics in the early 1900s and to Einsteinʼs theory of relativity.
Gioavanni Schiaparelli was an Italian astronomer who lived from 1835 to 1910. He observed the pattern of straight lines on the surface of Mars and called them ʻcanaliʼ, an Italian word for ʻchannelsʼ. Unfortunately, ʻcanaliʼ was mistranslated into ʻcanalsʼ, which implied that artificial structures existed on the red planet. This caused a flood of study on Mars, with many scientists expecting to find life there. Gioavanni also studied comets and how they caused meteor showers.
EN HEDUʼ ANNA
En Heduʼ Anna lived in Babylon around 2354BC. Her father Sargon created the Sargonian Dynasty of Babylon during that time. En Heduʼ was the chief priestess of the Moon Goddess of the city of Babylon. She played an extremely powerful role as she was the only person who could name any new ruler to the city. Sumeria and Babylon were the first cities to establish the concept of astronomy and mathematics. These disciplines were created and controlled by the priests and priestesses of the cities. Therefore, En Heduʼ was one of the primary forerunners of astronomy and mathematics. She, along with other priests, created several observatories inside religious temples to view the stars and moon. Maps were made of these celestial bodiesʼ movements. In addition, En Heduʼ helped create one of the first religious calendars, which is still used in certain religions to celebrate Easter, Passover and other religious events. En Heduʼ was the fi rst female name to be recorded in technical history.
Thales was a Greek philosopher who lived from 624BC to 546BC. He is considered the father of Greek science, mathematics and philosophy. He is the first person to have asked questions about the nature of the universe and considered the answers without thinking of gods or demons. This was a crucial step in scientific reasoning and led to an intellectual explosion which lasted hundreds of years. Thales also used Egyptian and Babylonian astronomical records to predict an eclipse in 585BC.
Pythagoras was an ancient Greek philosopher who lived from 580BC to 520BC. He founded a school in Croton, Greece which made outstanding contributions to the field of mathematics. Pythagoras and his cult members believed that everything was related to mathematics and agreed that, ultimately, "all is number.” Pythagoras is also famous for his study of sound and his theorem relating the lengths of the sides of a right triangle. This theorem is called the Pythagoras Theorem.
Socrates was a Greek philosopher who lived from 470BC to 399BC. He turned Greek attention towards questions of ethics and virtue. Although Socrates was not a scientist, his way of questioning to find out answers laid the foundation for the way that science works today. Socrates spent much time in the Athens marketplace where he held conversations with townspeople. He was known for exposing ignorance and conceit. At the age of 70, he was convicted of atheism and corruption of the young. He was sentenced to death and had the opportunity to escape from prison, but he chose not to. He valued the law so much that he chose to fulfil his sentence of death by drinking hemlock (a poison) instead of escaping and living in exile for the rest of his life. An account of his death was recorded by Plato, one of Socratesʼ students.
Democritus was a Greek philosopher who lived from 470BC to 380BC. He developed the concept of the ʻatomʼ. He believed that everything in the universe was made up of atoms, which were microscopic and indestructible. He had many remarkable insights for his time. He understood that the Milky Way was a large collection of stars and also thought that space was limitless.
Plato was a Greek philosopher who lived from 427BC to 327BC. He founded the Academy in Athens, a school which made many important scientific discoveries during ancient times. Although Plato made no important discoveries in mathematics himself, he played a crucial role in developing a more rigorous approach to mathematics. He believed in absolute truth and he believed that mathematics was the way to figure out those truths.
Plato is also considered the inventor of philosophic argument, having written several works involving Socratic dialogue such as ʻThe Republicʼ.
Aristotle lived from 384BC to 322BC and was a Greek philosopher. He was one of the greatest thinkers of the world and his written works encompassed all major areas of thought. Aristotle mistakenly believed that the Earth was at the centre of the universe and was made up of only four elements–earth, water, air and fire. He also thought that celestial bodies such as the sun, moon and stars were erfect and divine and made of a fifth element called ʻetherʼ.
Archimedes was a renowned Greek mathematician and engineer who lived from 287BC to 212BC. His greatest contributions are in the field of geometry and in the development of war machines. Legend has it that Archimedes discovered his famous theory of buoyancy while taking a bath. He was so excited that he ran naked through the streets of Syracuse shouting "Eureka, eureka!” (I have found it!) Archimedes also saved the city of Syracuse from a Roman siege by constructing a lens which focused the sunʼs light and burned Romeʼs fleet of ships.
Eratosthenes lived from 276BC to 194BC. He was a Greek scientist who studied astronomy, geography and mathematics. Eratosthenes spent most of his life in the city of Alexandria in Egypt. He is famous for making the first near-correct measurement of the size of the Earth and did this around 240BC. The Library of Alexandria was the most famous library in the world in ancient times. Eratosthenes was the second person to be head librarian there. Besides figuring out the size of the Earth, Eratosthenes made several other important inventions and discoveries. He invented an easy method of finding out prime numbers. That mathematical method is now called the Sieve of Eratosthenes. He also made a map of the whole world and invented a mechanical device that astronomers used for many years to figure out where the stars were in the sky and how they appeared to move (as the Earth turns). That device was called the ʻarmillary sphere’. Eratosthenes also made a catalogue of stars that had 675 stars listed in it. A crater on Earthʼs Moon is named after Eratosthenes.
Hipparchus was a Greek astronomer who lived from 190BC to 120BC. He created the first accurate star map and kept a catalogue of over 850 stars with their relative brightness. He also developed the system of epicycles where everything in space moved in perfect circles and preserved the Earth-centred universe of Aristotle. Hipparchus compiled a table of chord lengths, similar to modern trigonometry tables, and is considered to be the founder of trigonometry, a branch of mathematics which studies the angles of the sides of a triangle.
Ptolemy was a Greek astronomer who lived from 85BC to 165BC. He put together his own ideas with those of Aristotle and Hipparchus and formed the Geocentric Theory. This theory states that the Earth is at the centre of the universe and all other heavenly bodies circle it, a theory which was considered true for 1,400 years until the time of Copernicus. Ptolemy is also famous for his work in geography. He was the first person to use lines of longitude and latitude to identify places on the face of the Earth.
Hypatia was an Egyptian mathematician and philosopher who was born in the 4th Century AD. She taught mathematics, astronomy and philosophy at the Neoplatic School in Alexandria, Egypt. She was the daughter of Theon, a famous mathematician of the time. Hypatia wrote three books on mathematics and astronomy. In addition, she invented several tools relating to astronomy and the Earth sciences. They include a device for measuring water level, a distillation machine, an astrolabe (instrument that fixes the positions of the sun and stars), a planisphere and a hydrometer an instrument that measures the specific gravity of liquids.
ABU JA’FAR AL-KHWARIZMI
Abu Ja’far al-Khwarizmi was an Arab mathematician who lived from 780AD to 850AD. At a time when the diffusion of ideas was very slow due to the lack of cross-cultural communication, Abu Ja’far wrote a book which contained many important mathematical concepts of the Middle East. This book revolutionised European mathematics. It introduced the decimal system, as well as rules for solving equations and doing geometry.
Leonardo Fibonacci was an Italian mathematician who lived from 1175AD to 1250AD. He went on business trips with his father and was exposed to many different mathematical techniques used throughout the world. He collected these ideas in books for people to learn without having to travel as he had. His writings introduced Arabic numerals into European mathematics. He also made significant contributions to mathematics in number theory and on recursive sequences. He is most famous for the Fibonacci Sequence in which each number is the sum of the previous two.