Henri Becquerel

French physicist Henri Becquerel was one of the first nuclear scientists. He worked in Paris, where, together with Polish-born French physicist Marie Curie and her husband Pierre, he discovered radioactivity in uranium. He then went on to discover other radioactive elements. Becquerel developed the work of German physicist Wilhelm Rontgen (1845–1923), who discovered X-rays. An interest in photography helped Becquerel to discover the link between radioactivity, light, and magnetism. His work led to scientists using radioactivity to produce X-ray images. In 1903 Becquerel shared the Nobel Prize for physics with the Curies.

Wilhelm Röntgen

The discovery of X-rays in 1895 by the Prussian physicist Wilhelm Rontgen saw the beginning of a new age of physics thinking that the rays were unrelated to light and being uncertain of their nature, he called them X-rays. Rontgen discovered that when X-rays were directed through the body of a living person, the bones cast shadows on a photographic plate placed behind the body. X-rays are now also used in concentrated doses to treat cancer. Rontgen was the first person to be awarded the Nobel Prize for physics, which he received in 1901. The name Rontgen is now given to a unit of radiation, either X-rays or gamma rays.

Niels Bohr

Danish physicist Niels Bohr became famous for creating a new way of picturing the structure of the atom that led to the birth of modern nuclear physics. He studied in London, England, with two English physicists, Ernest Rutherford (1871–1937) and J. J Thomson (1856–1940), applying quantum theory to Rutherford's ideas about the structure of the atom. This resulted in the «Rutherford-Bohr atom.» Fled In Back in Copenhagen in 1916, Bohr discovered the principle used to build nuclear weapons. In 1943 he fled German-occupied Denmark for the United States, where he advised on the development of the atomic bomb.

Ernest Rutherford

The new Zealand-born British physicist Ernest Ru­therford laid the foundation for the development of nuclear physics and modern quantum theory. He investigated radioactivity and the nature of alpha (positively charged) particles. His most significant discovery was the nature of the structure of the atom. He realized through his experiments that the positive charge of an atom is concentrated at its center in a tiny, dense nucleus. Rutherford's work and leadership inspired two generations of scientists. In 1908 he received the Nobel Prize for chemistry, and in 1925 he became president of the Royal Society, London.

Joseph Thomson 

The English physicist Joseph Thomson made a major breakthrough in scientific understanding of the structure of the atom, proposing a model that became known as the Thomson atom. His work provided practical proof of many of the new theories that were being put forward about atomic structure at the time. Several years later, in 1906, he received a Nobel Prize for physics for his research into the electrical conductivity of gases. Thomson was a great teacher and an outstanding scientist. Seven of his students and assistants also received Nobel Prize for their work.

Lord Kelvin

Scottish mathematician and physicist Lord Kelvin (born in Northern Ireland as William Thomson) was the founder of modern British physics. His name is given to a unit of temperature, equivalent to 1 Celsius ©, but on a scale that takes 0 to be – 273 C (–459 F). Kelvin calculated that this was the lowest possible temperature any matter could achieve. This temperature is known as absolute zero, and the scale is called the absolute, or Kelvin, scale. Kelvin’s interests spread across the whole field of science from energy to geology. His work opened the way for many of the great scientific discoveries in Europe in the 1800s and early 1900s.

Robert Boyle

Born in Lismore, Ireland, Boyle became well known in his lifetime for his research in physical chemistry. His work on the properties of gases led him to put forward Boyle's Law in 1662. This stated that the pressure and volume of a gas are inversely proportional: this means that as one increases the other reduces. Like many scientists of his time, Boyle was a philosopher. He questioned the ideas of the Greek philosopher Aristotle (384 BC–322 BC), whose theories had been revived in the 1500s by Italian thinkers. Boyle was also a committed Christian, who tried to use science to confirm his beliefs.

Pierre Curie

Born in Paris, France, Pierre Curie became famous for his work on radioactivity and magnetism. From an early age he had great ability in mathematics. This led to his graduating from the University of Paris at just 18. His marriage to Paris immigrant Maria Sklodowska was the beginning of a world-famous partnership. Together they isolated two new radioactive elements, polonium and radium, and shared a Nobel Prize for physics in 1903 for their discovery of radioactivity. Pierre also worked on the properties of radioactive elements, identifying the existence of positive, negative, and neutral particles within an atom.

Marie Curie

Polish-born physicist Marie Curie and her French husband Pierre are famous for their work on radioactivity. They were inspired by the work of the French physicist Henri Becquerel (1852–1908). Marie Curie was the first to use the term «radioactive» for substances that have considerable electromagnetic activity.

She also isolated two new radioactive elements, polonium and radium.

After Pierre's death, she took over his job as professor of physics at the University of Paris, the first woman to teach there. She continued her research, looking for medical uses for radioactivity. She was awarded the Nobel Prize for physics in 1903 and for chemistry in 1911.

Maria Goeppert Mayer

The German-born American physicist Maria Goeppert Mayer is renowned for her work in nuclear physics. She studied the existing ideas about the structure and bonding properties of an atom. She then went on to develop her own theories, which are still in use today. Goeppert Mayer emigrated from Germany to the United States in 1931, and received funds that enabled her to pursue her ideas. In 1963 Goeppert Mayer shared a Nobel Prize with two other physicists, the German Hans Jensen (1907–1973) and the American Eugene Wigner (b. 1902), or their independent work on nuclear shell structures.

Lise Meitner

The Austrian nuclear physicist Lise Meitner is remembered for her discovery of the radioactive element protactinium. She studied radioactivity with experts in atomic theory and produced important work, despite having overcome both racial (she was Jewish) and sexual discrimination. In 1938 she fled Nazi Germany and went to neutral Sweden. This gave her the chance to work on her theory of nuclear fission (as she named it), using data from German scientists that described how they had actually split an atom. Meitner distanced herself from the first use of the theory – the production of an atomic bomb.