Ernest Rutherford, 1st Baron Rutherford of Nelson (30 August 1871 – 19 October 1937), was a scientist from New Zealand who studied physics and chemistry. He made important discoveries in the fields of atomic and nuclear physics. He was called "the father of nuclear physics" and "the greatest experimentalist since Michael Faraday." In 1908, he received the Nobel Prize in Chemistry for his work on the breakdown of elements and the study of radioactive materials.

Rutherford discovered the concept of radioactive half-life, identified the radioactive element radon, and named alpha and beta radiation. With Thomas Royds, he proved that alpha radiation is made of helium nuclei. In 1911, he proposed that atoms have their charge concentrated in a tiny nucleus. He reached this conclusion by studying how alpha particles scattered when they hit a gold foil, an experiment conducted by Hans Geiger and Ernest Marsden. In 1912, he invited Niels Bohr to join his lab, which led to the Bohr model of the atom. In 1917, he conducted the first artificial nuclear reaction by bombarding nitrogen nuclei with alpha particles. These experiments helped him discover a subatomic particle he first called the "hydrogen atom," later renamed the proton. He also worked with Henry Moseley to develop the atomic numbering system. His other contributions include progress in radio communications and ultrasound technology.

In 1919, Rutherford became Director of the Cavendish Laboratory at the University of Cambridge. Under his leadership, James Chadwick discovered the neutron in 1932. That same year, John Cockcroft and Ernest Walton, working under Rutherford, performed the first controlled experiment to split a nucleus. For his scientific achievements, Rutherford was honored as a baron in the United Kingdom. After his death in 1937, he was buried in Westminster Abbey near Charles Darwin and Isaac Newton. The chemical element rutherfordium (104 Rf) was named after him in 1997. In 1999, he was named the tenth greatest physicist of all time.

Early life and education

Ernest Rutherford was born on August 30, 1871, in Brightwater, New Zealand. He was the fourth of twelve children born to James Rutherford, a farmer and mechanic from Perth, Scotland, and Martha Thompson, a schoolteacher from Hornchurch, England. His birth certificate incorrectly listed his name as "Earnest," but his family called him "Ern."

At age 5, Rutherford moved to Foxhill, New Zealand, and attended Foxhill School. In 1883, when he was 11 years old, his family relocated to Havelock, located in the Marlborough Sounds. This move was to be closer to the flax mill operated by his father. He studied at Havelock School during this time.

In 1887, Rutherford earned a scholarship to study at Nelson College on his second attempt. During his first examination, he achieved the highest score among students from Nelson, earning 580 out of 600 possible marks. After receiving the scholarship, Havelock School gave him a five-volume book set titled The Peoples of the World. He studied at Nelson College from 1887 to 1889, served as head boy in 1889, and played rugby for the school team. He was offered a government cadetship but refused it because he still had 15 months of college left.

In 1889, Rutherford won another scholarship to study at Canterbury College, part of the University of New Zealand, from 1890 to 1894. He joined the debating society and the Science Society at Canterbury. He earned a B.A. in Latin, English, and Mathematics in 1892, an M.A. in Mathematics and Physical Science in 1893, and a B.Sc. in Chemistry and Geology in 1894.

Later, Rutherford invented a new type of radio receiver. In 1895, he received an 1851 Research Fellowship from the Royal Commission for the Exhibition of 1851, which allowed him to travel to England for postgraduate studies at the Cavendish Laboratory at the University of Cambridge. In 1897, he was awarded a B.A. Research Degree and the Coutts-Trotter Studentship from Trinity College, Cambridge.

Career and research

When Rutherford began his studies at Cambridge, he was one of the first "aliens" (people without a Cambridge degree) allowed to do research at the university. He was also honored to study under J. J. Thomson.

With Thomson's support, Rutherford detected radio waves at 0.5 miles (800 m), which made him the world record holder for the farthest distance over which electromagnetic waves could be detected. However, when he shared his results at a meeting in 1896, he learned that Guglielmo Marconi had already sent a message across nearly 10 miles (16 km) using radio waves.

Under Thomson's guidance, Rutherford studied how X-rays affected gases, leading to the discovery of the electron. Thomson presented these results in 1897. After learning about Henri Becquerel's work with uranium, Rutherford began studying its radioactivity and identified two types of radiation that differed from X-rays in how deeply they could penetrate matter. In Canada, he introduced the terms "alpha ray" and "beta ray" to describe these two types of radiation.

In 1898, Rutherford accepted the Macdonald Chair of Physics at McGill University in Montreal, Canada, based on Thomson's recommendation. From 1900 to 1903, he worked with chemist Frederick Soddy, who later won a Nobel Prize in Chemistry in 1921. Together, they studied the noble gas emitted by radioactive thorium, which they named "thoron." Later, they identified this gas as radon (Rn), an isotope of radon. They also found other substances, including "Thorium X" (later identified as radon) and traces of helium. They worked with samples of "Uranium X" (protactinium) from William Crookes and radium from Marie Curie. Rutherford and Soddy discovered that radioactive materials decay at a constant rate, which they called "half-life." They published their findings in a paper titled "Law of Radioactive Change." This challenged the idea that atoms were indestructible, as radioactivity showed atoms could break apart into other substances.

In 1903, Rutherford studied a third type of radiation discovered by French chemist Paul Villard in 1900. He named it "gamma ray" because it had much greater penetrating power than alpha or beta rays. These three types of radiation—alpha, beta, and gamma—are still widely used today. In 1904, Rutherford proposed that radioactivity could explain how the Sun has remained hot for millions of years, supporting the theory of slow biological evolution on Earth. This idea countered earlier claims by physicist Lord Kelvin that the Earth was much younger due to limited energy sources.

In 1907, Rutherford returned to Britain to take the Langworthy Professorship at the Victoria University of Manchester. There, he continued studying alpha radiation. With Hans Geiger, he developed tools like zinc sulfide scintillation screens and ionization chambers to count alpha particles. By analyzing the charge on these particles, Rutherford determined that alpha particles carried a charge of two. In 1910, he and Thomas Royds showed that alpha particles were actually helium nuclei by trapping them in a tube and observing the helium gas they produced. In 1910, Rutherford, Geiger, and mathematician Harry Bateman published a paper describing the first analysis of radioactive emission patterns, now called the Poisson distribution.

Rutherford continued making important discoveries after winning the Nobel Prize in 1908. In 1909, he directed Hans Geiger and Ernest Marsden in an experiment that proved atoms have a dense, positively charged core called the nucleus. This experiment involved firing alpha particles at a thin gold foil and observing their unexpected deflection. Rutherford described the results as "the most incredible event" of his life, comparing it to firing a shell at tissue paper and having it bounce back. His findings led to the discovery of the nucleus.

In 1912, Rutherford worked with Niels Bohr, who proposed that electrons orbit the nucleus in specific paths. Bohr combined this idea with Max Planck's quantum theory to create the Bohr model of the atom, which remains a foundation for modern atomic physics.

During World War I, Rutherford helped develop technology for submarine detection using piezoelectricity. This work later contributed to the development of ultrasound, though it is a common misconception that Rutherford invented sonar.

In 1913, Rutherford and H.G. Moseley developed the atomic numbering system by studying how cathode rays interacted with different elements. Their experiments showed that each element has a unique structure, leading to the discovery of the atomic nucleus. Rutherford theorized that the hydrogen atom, which carries a positive charge, might be a "positive electron" found in all atoms.

In 1919, Rutherford tested this theory by showing that alpha particles could knock protons (hydrogen atoms) out of nitrogen and other light elements. He observed that these protons had a unit charge and 1/4 the momentum of alpha particles.

Rutherford returned to the Cavendish Laboratory in 1919, succeeding J. J. Thomson.

Personal life and death

In 1900, at St Paul's Anglican Church in Papanui, Christchurch, Rutherford married Mary Georgina Newton (1876–1954). He had been engaged to her before leaving New Zealand. The couple had one daughter, Eileen Mary (1901–1930). She married physicist Ralph Fowler and died during the birth of her fourth child. Rutherford enjoyed playing golf and driving as hobbies.

While working in Manchester, Rutherford lived in the suburb of Withington on Wilmslow Road. The house is now called Rutherford Lodge and was honored with a blue plaque in 2012. A memorial is also placed on the pavement in front of Withington Library.

Before his death, Rutherford had a small hernia that he did not have repaired. Over time, the hernia became serious and caused him severe illness. He had an emergency operation in London but passed away four days later in Cambridge on 19 October 1937, at the age of 66. Doctors called his cause of death "intestinal paralysis." After being cremated at Golders Green Crematorium, he was buried in Westminster Abbey, near Isaac Newton, Charles Darwin, and other well-known British scientists.

Legacy

At the opening session of the 1938 Indian Science Congress, where Rutherford was expected to speak before his death, James Jeans, an astrophysicist, gave a speech in Rutherford's place. He called Rutherford "one of the greatest scientists of all time."

Rutherford is known as "the father of nuclear physics" because his research and the work done by scientists in his laboratory helped prove the nuclear structure of atoms and the role of radioactive decay as a nuclear process. Patrick Blackett, a scientist who worked under Rutherford, used natural alpha particles to show that nuclear transmutation could be induced. Later, Rutherford's team used protons from an accelerator to demonstrate artificial nuclear reactions and transmutation.

Rutherford died before the idea of controlled nuclear chain reactions, proposed by Leó Szilárd, became a reality. However, Szilárd said that a speech Rutherford gave about his artificial transmutation of lithium, published in The Times on September 12, 1933, inspired him to consider the possibility of a controlled energy-producing nuclear chain reaction.

In his speech, Rutherford discussed the 1932 work of his students John Cockcroft and Ernest Walton, who used protons from a particle accelerator they built to split lithium atoms into alpha particles. Rutherford noted that the energy released during this process was very large. However, he also recognized that the energy required to operate the accelerator and the inefficiency of splitting atoms this way made the process impractical for producing energy. (Accelerator-induced fission of light elements remains too inefficient for energy production today.)

The element rutherfordium, Rf, with an atomic number of 104, was named in honor of Rutherford in 1997.

In popular culture

In episode 11 of season 13, titled "Staring Blindly into the Future," which aired on January 13, 2020, actor Andrew Hodwitz plays the character Rutherford in the Canadian television period detective series Murdoch Mysteries.

Publications

• Radioactivity (1904), Second edition (1905), ISBN 978-1-60355-058-1
• Radioactive Transformations (1906), ISBN 978-1-60355-054-3
• Radioaktive Substanzen und ihre Strahlungen. Cambridge: University Press. 1933.
• Radioaktive Substanzen und ihre Strahlungen (in German). Leipzig: Akademische Verlaggesellschaft. 1913.
• Radioactive Substances and their Radiations (1913)
• The Electrical Structure of Matter (1926)
• The Artificial Transmutation of the Elements (1933)
• The Newer Alchemy (1937)

• Ernest Rutherford (1899). "Uranium Radiation and the Electrical Conduction Produced by it." Philosophical Magazine. 47 (284): 109–163.
• Ernest Rutherford (1903). "XV. The Magnetic and Electric Deviation of the Easily Absorbed Rays from Radium." Philosophical Magazine, Series 6, 5: 177–187.
• Ernest Rutherford (1906). "The Mass and Velocity of the α Particles Expelled from Radium and Actinium." Philosophical Magazine, Series 6, 12(70): 348–371. doi: 10.1080/14786440609463549.
• Ernest Rutherford; Thomas Royds (1909). "XXI. The Nature of the α Particle from Radioactive Substances." The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 17 (98): 281–286. doi: 10.1080/14786440208636599. ISSN 1941-5982.
• Ernest Rutherford (1911). "The Scattering of α and β Particles by Matter and the Structure of the Atom" (PDF). Philosophical Magazine, Series 6, 21(125): 669–688. doi: 10.1080/14786440508637080.
• Ernest Rutherford (1912). "The Origin of β and γ Rays from Radioactive Substances." Philosophical Magazine, Series 6, 24(142): 453–462. doi: 10.1080/14786441008637351.
• Ernest Rutherford; John Mitchell Nuttal (1913). "Scattering of α-Particles by Gases." Philosophical Magazine, Series 6, 26(154): 702–712. doi: 10.1080/14786441308635014.
• Ernest Rutherford (1914). "The Structure of the Atom." Philosophical Magazine, Series 6, 27(159): 488–498. doi: 10.1080/14786440308635117.
• Ernest Rutherford (1938). "Forty Years of Physics." In Needham, Joseph; Pagel, Walter (eds.). Background to Modern Science: Ten Lectures at Cambridge Arranged by the History of Science Committee 1936. Cambridge University Press.
• Ernest Rutherford (1913). Radioactive Substances and their Radiations. Cambridge University Press.
• Ernest Rutherford (1936). "Radioactivity and Atomic Structure." Journal of the Chemical Society. 1936: 508–516. doi: 10.1039/JR9360000508.
• "Disintegration of the Radioactive Elements." Harper's Monthly Magazine, January 1904, pages 279–284.