Galileo Galilei (1564-1642)
Galilei is most famous for improving the telescope, to be used to study the planets and stars. In Galilei’s time, there weren’t ‘really’ scientists as we now know them. People studied the works of classic philosophers like Plato, but didn’t run experiments to test out their theories.
Galilei wanted to test the principles and see if he could observe them, laying the foundation for the scientific method. In 1609, Galilei heard of an invention from the Netherlands called the telescope, that could make far away objects appear much closer.
He made great improvements to the original telescope, and his version was eventually used throughout Europe. Using his telescope, he made many discoveries, such as the four large moons around Jupiter, the phases of the planet Venus, and the existence of craters on the moon.
Johannes Kepler (1571-1630)
Kepler was a famous astronomer and mathematician, who came up with the planetary laws of motion. His interest in astronomy stemmed from two events of his childhood: being shown a great comet by his mother, and being taken out at night by his father to see a lunar eclipse.
He made several discoveries about how the planets moved, such as the fact that the planet Mars moved in an oval-shaped orbit. These discoveries removed all doubts that the planets go around the Sun.
For a long time, most scientists believed that the Sun travelled around the planets. Kepler later went on to invent the present-day form of the astronomical telescope, and published the first scientific study of light and lenses.
Isaac Newton (1643-1727)
Isaac Newton was a scientist, mathematician and astronomer, and developed a number of scientific theories. Einstein himself said that Newton was the smartest person who ever lived.
In 1687, Newton published his most important work, Principia, which used mathematics to explain gravity and motion. In this work, he detailed his three laws of motion, which lie at the heart of the science of movement.
He also detailed his discovery of the law of universal gravitation, which helps to understand the movements of the planets and the Sun. In addition to this, he built the world’s first working reflecting telescope, and proved that sunlight is made up of all the colours of the rainbow.
Michael Faraday (1791-1867)
Faraday was the greatest experimental physicist of the nineteenth century, despite the fact that he had minimal school education, and knew no higher mathematics. In the 19th century, little was known about electricity.
Faraday discovered electromagnetism, the fact that electricity flowing in a wire can act like a magnet. He also discovered electrochemistry, how electricity can make chemicals change.
Building on his interest in magnets, he showed the relationship between magnetism and rays of light, and invented the first electric motor. Without him, we wouldn’t be able to use electricity in technology.
James Clerk Maxwell (1831-1879)
Maxwell was a Scottish scientist, who submitted his first paper at just 14 years old. He is most famous for his theory of electromagnetic radiation, which brought together electricity, magnetism and light as different manifestations of the same phenomenon, for the first time.
This paved the way for radio, television and mobile phones. In addition to this, Maxwell developed the concept of the colour photograph, and explained the action of Saturn’s rings. He did this over 100 years before the Voyager spacecraft confirmed his theory.
Marie Curie (1867-1934)
Marie Curie grew up in Poland, but eventually moved to France, studying at the Sorbonne. After earning her degree in physics, she entered the world of scientific research. One day, she was examining a material called pitchblende, expecting there to be few rays from the uranium present. Instead, she discovered several rays.
From this, she realised there must be an undiscovered element in pitchblende, and set about discovering it. Eventually, she discovered that there were two new elements in pitchblende, radium and polonium. She named radium so because of its strong rays, and polonium after her homeland Poland.
She was awarded the Nobel Prize in Physics for her work in radiation, becoming the first woman to receive the prize. With her receipt of the Nobel Prize in Chemistry, she was the first person to be awarded two Nobel Prizes.
Ernest Rutherford (1871-1937)
Rutherford was a New Zealand-born English physicist, who is commonly known as the father of nuclear physics. His greater discovery was the Rutherford atomic model. Although scientists were aware that atoms existed, they didn’t know what they are made of or how they worked.
Rutherford proposed the idea that the atom was made up of mostly empty space, and its mass was concentrated in the tiny nucleus. Although his model was later revised, it was an important step in understanding atoms. He is also famous for making the first nuclear reaction, by changing nitrogen gas to oxygen gas.
Albert Einstein (1879-1955)
Albert Einstein made some of the most important discoveries and developed some of the most crucial theories in all of science. His face and name are often seen as the picture of the ultimate scientist. He is most known for his Theory of Relativity, which transformed the way scientists look at the world.
One equation from the theory is E=mc2, in which ‘c’ is the constant speed of light, and E (energy) is related to mass (m.) The theory explains how time and distance may change due to the ‘relative’ or different speed of the object and the observer. It has been used to develop many modern inventions, such as the atomic bomb and TVs.
Einstein also came up with many other discoveries, such as the fact that light is made up of particles called photons. Even though scientists at the time didn’t believe him, later experiments proved his theory and he was eventually awarded the Nobel Prize for Physics. Many of his papers helped move forward our understanding of the world.
Niels Bohr (1885-1962)
Bohr is generally regarded as one of the greatest physicists of the 20th century, for his work on atoms. He designed his own model of the atom, combining the ideas of the British scientist Ernest Rutherford with the theories of physicists Max Planck and Albert Einstein.
His model helped to understand how atoms are structured and how the parts of atoms behave. For this work he received a Nobel Prize in Physics. He also helped with the war effort, by helping Jewish scientists escape from Germany and working at his institute in Copenhagen. Bohr even helped scientists in the United States to develop their own atomic bomb, as they feared Germany was trying to develop one.
Stephen Hawking (1942-2018)
Hawking, a scientist and astrophysicist, was born on the 300th anniversary of the death of Galileo Galilei. While completing his PhD at Cambridge, he began to become clumsy, and noticed his speech was slurred. A doctor diagnosed him with ALS, and gave him over a few years to live; a prophecy that turned out to be false.
Although he couldn’t talk for much of his life and had to use a wheelchair, he could communicate via a touch pad computer and voice synthesiser. He spent much of his academic work researching black holes and space-time theories, and became a noted expert on relativity and black holes. His most famous theory was when he proved that black holes emit some radiation, with this radiation becoming known as Hawking Radiation.
Hawking also wrote several books, such as A Brief History in Time. He wrote about subjects like the big bang and black holes so that the average reader could understand.