Important historic dates in science

June 30: Atomic bomb
In 1946, the first U.S. atomic bomb dropped from an airplane over water was named "Able," a part of Operation Crossroads. A U.S. Air Force B-29 Superfortress, Dave's Dream, was used to deliver the bomb, which was dropped over the Bikini Lagoon in the Pacific Ocean onto a target group of 73 ships moved there for the purpose. The explosion caused a 520-foot burst. The Gilliam and Carlisle transport ships were sunk, and 18 other ships were damaged.

June 29: George Ellery Hale
(Born June 29, 1868: Died February 21, 1938)
American astronomer known for his development of important astronomical instruments. To expand solar observations and promote astrophysical studies he founded Mt. Wilson Observatory (Dec 1904). He discovered that sunspots were regions of relatively low temperatures and high magnetic fields. Hale hired Harlow Shapley and Edwin Hubble as soon as they finished their doctorates, and he encouraged research in galactic and extragalactic astronomy as well as solar and stellar astrophysics. Hale planned and tirelessly raised funds for the 200" reflecting telescope at the Palomar Mountain Observatory completed in 1948, after his death, and named for him - the Hale telescope.

June 28: Robert S. Ledley
(Born June 28, 1926)
American physicist and radiologist who invented the ACTA (Automatic Computerized Transverse Axial) diagnostic X-ray scanner, the first whole-body computerized tomography (CT) machine (U.S. patent no. 3,922,552) which revolutionized medical diagnosis. The ACTA can make a three-dimensional analysis of all organs and parts of the body in a series of cross-section images using thin X-ray beams and high power computer processing of the collected data. Using the ACTA, diagnosis of tumours, infection or bleeding is possible even deep within large organs, and it can give improved radiation therapy for cancer. The framework could be tilted to give results from planes other than vertical.

June 27: Merle Antony Tuve
(Born June 27, 1901: Died May 20, 1982)
American research physicist and geophysicist who (with Gregory Breit) made the first use pulsed radio waves to explore the ionosphere. He devised the necessary detecting equipment to measure the time between receiving a direct radio pulse and a second pulse reflected from the ionosphere. The observations he made provided the theoretical foundation for the development of radar. Tuve, with Lawrence R. Hafstad and Norman P. Heydenburg, made the first and definitive measurements of the nuclear force between proton-proton force at nuclear distances. During WW II he developed the proximity fuse. Following the war, he made important contributions to experimental seismology, radio astronomy, and optical astronomy.

June 26: Paul Niggli
(Born June 26, 1888)
Swiss mineralogist who originated the idea of a systematic deduction of the patterns in the internal structure of crystals by means of X-ray data. He supplied a complete outline of methods that have since been used to determine these patterns. There are 230 possible different internal patterns for different crystals. Because the patterns describe a three-dimensional arrangement, they are known as space groups. Niggli also developed a notation that described the individual space groups, and co-authored a definitive set of tables describing them.

June 25: Ph.D. for Curie
In 1903, Marie Curie went before the examination committee for her Ph.D. Later in this same year she was awarded a Nobel Prize for her research.

June 24: Victor Francis Hess
(Born June 24, 1883: Died December 17, 1964)
Austrian-born physicist who was a joint recipient (with Carl D. Anderson of the United States) of the Nobel Prize for Physics in 1936 for his discovery of cosmic rays, high-energy radiation originating in outer space. He emigrated to the United States in 1938 and was later naturalized. By means of instruments carried aloft in balloons, Hess and others proved that radiation that ionizes the atmosphere is of cosmic origin. He c (1939) a 27-day cycle of cosmic-ray intensity to the magnetic field of the sun and correlated it with the 27-day period of rotation of the sun. He also worked on devising methods for detecting minute quantities of radioactive substances. Hess made basic contributions to an understanding of radiation and its effects on the human.

June 23: Étienne-Louis Malus
(Born June 23, 1775: Died February 23, 1812)
French physicist who discovered that light, when reflected, becomes partially plane polarized; i.e., its rays vibrate in the same plane. He served in Napoleon’s corps of engineers, fought in Egypt, and contracted the plague during Napoleon’s aborted campaign in Palestine. Posted to Europe after 1801, he began research in optics. In 1808, he discovered that light rays may be polarized by reflection, while looking through a crystal of Iceland spar at the windows of a building reflecting the rays of the Sun. He noticed that on rotating the crystal the light was extinguished in certain positions. Applying corpuscular theory, he argued that light particles have sides or poles and coined the word "polarization."

June 22: Sir Christopher Hinton
(Born May 12, 1901: Died June 22, 1983)
(Baron of Bankside) English engineer who was a leading figure in the development of the nuclear energy industry in Britain; he supervised the construction of Calder Hall, the world's first large-scale nuclear power station (opened in 1956). He first worked for Imperial Chemical Industries (ICI) where at age 29 he was appointed chief engineer of the Alkali Groups. While at ICI he was selected to start building nuclear power plants. Britain's first four such plants were completed in six years. He played a founding role in fast breeder technology. The decision to build the Dounreay Fast Reactor was made in 1954, which ran successfully for over two decades, until its planned shutdown in 1977, thus demonstrating the safe operation of the concept.

June 21: Herbert Friedman
(Born June 21, 1916: Died September 9, 2000)
American rocket and satellite astronomer who made made seminal contributions to the study of solar radiation. He joined the Naval Research Laboratory in 1940 and developed defense-related radiation detection devices during WW II. In 1949, he obtained the first scientific proof that X rays emanate from the sun. When he directed the firing into space of a V-2 rocket carrying a detecting instrument. Through rocket astronomy, he also produced the first ultraviolet map of celestial bodies, and gathered information for the theory that stars are being continuously formed, on space radiation affecting Earth and on the nature of gases in space. He also made fundamental advances in the application of x rays to material analysis.

June 20: X-ray burns
In 1918, the X-ray expert Dr. Eugene W. Caldwell, died of X-ray burns, in New York. Dr. Caldwell was Director of X-ray in New York City’s Bellevue Hospital, and his book The Practical Application of Roentgen Rays in Therapeutics was an accepted textbook on the subject. He received the fatal burns in the course of his X-ray research.

June 19: Silvanus Phillips Thompson
(Born June 19, 1851: Died June 12, 1916)
British physicist and historian of science. He was a recognised authority upon electricity, magnetism and acoustics and his writings are numerous including Elementary Lessons in Electricity and Magnetism published in 1881 which ran through some 40 editions and reprints. He was also known for contributions in electrical machinery, optics, and X rays. In 1884, he published his epoch-making work Dynamo-electric Machinery: a Manual for Students of Electrotechnics. Practically every designer of electrical machines gleaned his first information on the subject from this work. His lectures to the Royal Institution on Light, visible and invisible in book form and Polyphase Electric Currents and Motors were published in 1896.

June 18: Dudley R. Herschbach
(Born June 18, 1932)
American chemist and educator who shared (with Yuan T. Lee and John C. Polanyi) the Nobel Prize for Chemistry in 1986. He pioneered the use of molecular beams to elucidate the processes of chemical reactions. This study of reaction dynamics details the sequence of events and energy states of the atoms and molecules.

June 17: Chinese H-bomb
In 1967, China tested its first hydrogen bomb. This was China's sixth nuclear test, and its first full scale radiation implosion (Teller-Ulam) weapon test. The device contained U-235, lithium-6 deuteride, and U-238. It was detonated at 2960 m over the Lop Nur Test Ground after being dropped from an airplane, and had a yield of 3.3 megatons. (It was conducted only 32 months after Chinas's first atomic test, October 16, 1964, the shortest elapsed time for any nuclear weapons state. The country's first test was an atomic bomb, a pure-fission U-235 implosion fission device named "596." That device weighed 1550 kg with a 22 kiloton yield. No plutonium was available at the time of this first bomb was tested.)

June 17: Chinese H-bomb
In 1967, China tested its first hydrogen bomb. This was China's sixth nuclear test, and its first full scale radiation implosion (Teller-Ulam) weapon test. The device contained U-235, lithium-6 deuteride, and U-238. It was detonated at 2960 m over the Lop Nur Test Ground after being dropped from an airplane, and had a yield of 3.3 megatons. (It was conducted only 32 months after Chinas's first atomic test, October 16, 1964, the shortest elapsed time for any nuclear weapons state. The country's first test was an atomic bomb, a pure-fission U-235 implosion fission device named "596." That device weighed 1550 kg with a 22 kiloton yield. No plutonium was available at the time of this first bomb was tested.)

June 16: Julius Plücker
(Born June 16, 1801: Died May 22, 1868)
German mathematician and physicist whose work suggested the far-reaching principle of duality, which states the equivalence of certain related types of theorems. He also discovered that cathode rays (electron rays produced in a vacuum) are diverted from their path by a magnetic field, a principle vital to the development of modern electronic devices, such as television. At first alone and later with the German physicist Johann W. Hittorf, Plücker made many important discoveries in spectroscopy. Before Bunsen and Kirchhoff, he announced that spectral lines were characteristic for each chemical substance and this had value to chemical analysis. In 1862 he pointed out that the same element may exhibit different spectra at different temperatures.

June 15: Hubertus Stroghold
(Born June 15, 1898:)
German-American physiologist, known as the "father of space medicine." In the late 1920's, he began investigaing the physiological aspects of what he called the "vertical frontier" in Germany, when even simple aeromedicine was considered far-fetched. He emigrated to the U.S. to join the staff of the United States Air Force School of Aviation Medicine after WW II. Among the fundamental studies initiated were those in acceleration, noise and vibration, atmospheric control, weightlessness and nutrition. He invented the space cabin simulator for testing human reactions in a manned satellite, and contributed enormously to such space-travel problems as weightlessness, visual disturbances, and disruption of normal time cycles.

June 14: Atomic submarine Nautilus
In 1952, the keel was laid for the first American atomic submarine Nautilus in a ceremony attended by President Harry S. Trumann. It was built by the Electric Boat Company division of General Dynamics Corp. at Groton, Conn., under the supervision of Captain Hyman George Rickover. Its liquid-cooled atomic reactor provided power for steam turbines. The submarine was launched in early 1954, commisioned later that year. It was tested under nuclear power on January 17, 1955 and completed April 22, 1955.

June 13: Sunspots
In 1611, a publication on the newly discovered phenomenon of sunspots was dedicated. Narratio de maculis in sole observatis et apparente earum cum sole conversione. ("Narration on Spots Observed on the Sun and their Apparent Rotation with the Sun"). This first publication on such observations, was the work of Johannes Fabricius, a Dutch astronomer who was perhaps the first ever to observe sunspots. On March 9, 1611, at dawn, Johannes had used his telescope to view the rising sun and had seen several dark spots on it. He called his father to investigatethis new phenomenon with him. The brightness of the Sun's center was very painful, and the two quickly switched to a projection method by means of a camera obscura.

June 12: Sir Oliver Joseph Lodge
(Born June 12, 1851: Died August 22, 1940)
British physicist who perfected the coherer, a radio-wave detector and the heart of the early radiotelegraph receiver. He provided his laborary facilities to conduct the first clinical use of X-rays in England (February 7, 1896), at the request of surgeon Sir Robert Jones, to examine the wrist of boy who had accidentally shot himself.

June 11: Charles Fabry
(Born June 11, 1867: Died December 11, 1945)
French physicist who specialized in optics, devising methods for the accurate measurement of interference effects. He worked with Alfred Pérot, during 1896-1906, on the design and uses of a device known as the Fabry-Pérot interferometer, specifically for high-resolution spectroscopy, composed of two thinly silvered glass plates placed in parallel, producing interference due to multiple reflections. In 1913, Fabry demonstrated that ozone is plentiful in the upper atmosphere and is responsible for filtering out ultraviolet radiation from the Sun, protecting life on the surface of Earth from most of its harmful effects.

June 10: John Dollond
(Born June 10, 1706: Died November 30, 1761)
British maker of optical and astronomical instruments who developed (1758) and patented an achromatic (non- colour- distorting) refracting telescope and a practical heliometer, a telescope used to measure the Sun's diameter and the angles between celestial bodies. In the 1730's, Chester More Hall, an attorney with an interest in telescopes, first discovered that flint glass appeared to have a greater color dispersion than crown glass did at the same magnifications. Hall reasoned that if he cemented the concave face of a flint glass lens to the convex face of a crown glass lens, he could remove the dispersion properties (and thus, chromatic aberration) from both lenses simultaneously. Dollond learned of the technique in the 1750's and developed it.

June 9: Einstein published
In 1905, Albert Einstein published his analysis of Planck's quantum theory and its application to light. His article appeared in Annalen der Physik. Though no experimental work was involved, it was for these insights that Einstein earned his Nobel Prize.

June 8: Augusto Righi
(Born August 27, 1850: Died June 8, 1920)
Italian physicist who showed that radio waves displayed characterics of light wave behaviour in the manner of reflection, refraction, polarization and interference. Thus the nature of radio waves was similar to light, but with the difference of greater wavelength and a part of the same electromagnetic spectrum as light. He discovered magnetic hysteresis (1880). He was the first person to generate microwaves, and opened a whole new area of the electromagnetic spectrum to research and subsequent application. By 1900 also began work on X-rays. In 1903 he wrote the first paper on wireless telegraphy. His improvements on the work of Hertz were passed along to Guglielmo Marconi, who studied in Righi’s laboratory.

June 7: Charles Glover Barkla
(Born June 7, 1877: Died October 23, 1944)
British physicist who was awarded the Nobel Prize for Physics in 1917 for his work on X-ray scattering, which occurs when X rays pass through a material and are deflected by the atomic electrons. This technique proved to be particularly useful in the study of atomic structures. In 1903, his measurements showed that the scattering of x-rays by gases depends on the molecular weight of the gas. Both by observing polarization of x-rays (1904) and by experiments (1907) on the direction of scattering of a beam of x-rays he showed x-rays to be electromagnetic radiation like light (whereas, at the time, William Henry Bragg who held that x-rays were particles.) Barkla also discovered that each element has its own characteristic x-ray spectrum.

June 6: Heinrich Rohrer
(Born June 6, 1933)
Swiss physicist who, with Gerd Binnig, received half of the 1986 Nobel Prize for Physics for their joint invention of the scanning tunneling microscope. (Ernst Ruska received the other half of the prize.) Ruska's electron microscope of the 1930s was unable to show surface structure at the atomic level. Rohrer and Binnig began work in 1978 on a scanning tunneling microscope in which a fine probe passes within a few angstroms of the surface of the sample. A positive voltage on the probe enables electrons to move from the sample to the probe by the tunnel effect, and the detected current can used to keep the probe at a constant distance from the surface. As the probe moves in parallel lines, a 3D image of the surface can be constructed.

June 5: Dennis Gabor
(Born June 5, 1900: Died: February 8, 1979)
Hungarian-born British electrical engineer who won the Nobel Prize for Physics in 1971 for his invention of holography, a system of lensless, three-dimensional photography that has many applications. He first conceived the idea of holography in 1947 using conventional filtered-light sources. Because such sources had limitations of either too little light or too diffuse, holography was not commercially feasible until the invention of the laser (1960), which amplifies the intensity of light waves. He also did research on high-speed oscilloscopes, communication theory, physical optics, and television. Gabor held more than 100 patents.

June 4: William Thomas Astbury
(Born February 25, 1898: Died June 4, 1961)
English physical biochemist who was the first to make use of X-ray diffraction patterns to study the structure of nucleic acids (1937). Astbury researched the method under Bragg for seven years, then investigated the structure of wool in both the stretched and unstretched forms. From the difference in the diffraction patterns, he began to try to work ot the structure of protein molecules. His preliminary determination of the structure of nucleic acids were, in fact, wrong - but it gave impetus to Pauling's work with proteins, and to Crick and Watson's study of DNA structure. His work, slowly decoding the nature of molecular structure of virtually the largest organic materials, fibrous and globular proteins, was valuable to both science and industry.

June 3: Hale telescope
In 1948, the 200-inch (5.08 m) reflecting Hale telescope at the Palomar Mountain Observatory in California was dedicated. This was the first in the world with a 200-inch lens, which after casting was permitted to cool slowly over an 11 month period. The resulting 20-ton glass disk then required 11 years of careful grinding and polishing. The telescope was officially named after Dr. George Ellery Hale who conceived, designed and promoted this telescope, though he died before it was completed. On 1 Feb 1949, studies first began with observations were first made of the constellation Coma Berenices.

June 2: Eric Voice
(Born: June 2, 1924: Died September 11, 2004)
English nuclear scientist who volunteered to ingest a minute amount of plutonium as part of European research to track plutonium in the body's metabolism. He was one of 12 volunteers aged 26 to 67 who were injected with plutonium between 1992-98. Reuters reported on 8 Aug 1999 that Voice, age 73, had volunteered again to inhale plutonium for further study 18 months earlier. The miniscule dose was a soluble compound of Pu-237, which he regarded as having little risk, and he remained in good health. Sensitive detectors measured how much and where plutonium was retained, in which organs, and how quickly expelled. He was one of the first western scientists to visit Chernobyl after the explosion (1986). He died of unrelated natural causes.

June 1: 3K radiation
In 1965, A. Penzias and R. Wilson detected a 3 degree kelvin primordial background radiation using a horn reflector antenna built for radio astronomy. The Big Bang description of the origin of the universe took place 15 to 20 billion years ago in an explosion from a hot dense state. The high energy radiation produced when the universe was very young and very hot would have been absorbed and degraded as the universe expanded and cooled. The microwave background radiation first observed by Penzias and Wilson is thought to be a relic of this very early state, when the universe was only about a million years old. The uniformity of microwave background indicates that the universe was homogeneous until it was a few million years old.

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