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40-718: Charles Glover Barkla (7 June 1877 – 23 October 1944) was a British physicist , and the winner of the Nobel Prize in Physics in 1917 for his work in X-ray spectroscopy and related areas in the study of X-rays ( Roentgen rays ). Barkla was born in Widnes , England, to John Martin Barkla, a secretary for the Atlas Chemical Company, and Sarah Glover, daughter of a watchmaker. Barkla studied at

80-700: A master's degree like MSc, MPhil, MPhys or MSci. For research-oriented careers, students work toward a doctoral degree specializing in a particular field. Fields of specialization include experimental and theoretical astrophysics , atomic physics , biological physics , chemical physics , condensed matter physics , cosmology , geophysics , gravitational physics , material science , medical physics , microelectronics , molecular physics , nuclear physics , optics , particle physics , plasma physics , quantum information science , and radiophysics . The three major employers of career physicists are academic institutions, laboratories, and private industries, with

120-713: A lecture theatre at the University of Liverpool 's Physics department, as well as a Biophysics laboratory in the Biological science department, are named after him. In 2012 a gritter in Barkla's home town of Widnes was named in his honour, following a competition run by the local newspaper. In Widnes they have a Retirement housing Complex named Barkla Fields after Charles. Physicist Physicists can apply their knowledge towards solving practical problems or to developing new technologies (also known as applied physics or engineering physics ). The study and practice of physics

160-452: A minimum, the owner must possess a three-year bachelors or equivalent degree in physics or a related field and an additional minimum of six years' experience in a physics-related activity; or an Honor or equivalent degree in physics or a related field and an additional minimum of five years' experience in a physics-related activity; or master or equivalent degree in physics or a related field and an additional minimum of three years' experience in

200-505: A physics-related activity; a Doctorate or equivalent degree in Physics or a related field; or training or experience which, in the opinion of the Council, is equivalent to any of the above. Physicists may be a member of a physical society of a country or region. Physical societies commonly publish scientific journals, organize physics conferences and award prizes for contributions to the field of physics. Some examples of physical societies are

240-416: A professional practice examination must also be passed. An exemption can be granted to a candidate that has practiced physics for at least seven years and provide a detailed description of their professional accomplishments which clearly demonstrate that the exam is not necessary. Work experience will be considered physics-related if it uses physics directly or significantly uses the modes of thought (such as

280-474: A recent NELIOTA survey covering 283.5 hours of observation time discovering that at least 192 new craters of a size of 1.5 to 3 meters (4.9 to 9.8 ft) were created during the observation period. In 1978, Chuck Wood and Leif Andersson of the Lunar & Planetary Lab devised a system of categorization of lunar impact craters. They sampled craters that were relatively unmodified by subsequent impacts, then grouped

320-541: A speed of 90,000 km/h (56,000 mph; 16 mi/s). In March 2018, the discovery of around 7,000 formerly unidentified lunar craters via convolutional neural network developed at the University of Toronto Scarborough , Canada was announced. A similar study in December 2020 identified around 109,000 new craters using a deep neural network . Because of the Moon's lack of water , atmosphere , and tectonic plates , there

360-688: Is based on an intellectual ladder of discoveries and insights from ancient times to the present. Many mathematical and physical ideas used today found their earliest expression in the work of ancient civilizations, such as the Babylonian astronomers and Egyptian engineers , the Greek philosophers of science and mathematicians such as Thales of Miletus , Euclid in Ptolemaic Egypt , Archimedes of Syracuse and Aristarchus of Samos . Roots also emerged in ancient Asian cultures such as India and China, and particularly

400-448: Is little erosion, and craters are found that exceed two billion years in age. The age of large craters is determined by the number of smaller craters contained within it, older craters generally accumulating more small, contained craters. The smallest craters found have been microscopic in size, found in rocks returned to Earth from the Moon. The largest crater called such is about 290 km (180 mi) across in diameter, located near

440-536: Is the Nobel Prize in Physics , awarded since 1901 by the Royal Swedish Academy of Sciences . National physical societies have many prizes and awards for professional recognition. In the case of the American Physical Society , as of 2023, there are 25 separate prizes and 33 separate awards in the field. Chartered Physicist (CPhys) is a chartered status and a professional qualification awarded by

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480-529: The American Physical Society , the Institute of Physics , with the oldest physical society being the German Physical Society . Lunar crater Lunar craters are impact craters on Earth 's Moon . The Moon's surface has many craters, all of which were formed by impacts. The International Astronomical Union currently recognizes 9,137 craters, of which 1,675 have been dated. The word crater

520-683: The Institute of Physics . It is denoted by the postnominals "CPhys". Achieving chartered status in any profession denotes to the wider community a high level of specialised subject knowledge and professional competence. According to the Institute of Physics, holders of the award of the Chartered Physicist (CPhys) demonstrate the "highest standards of professionalism, up-to-date expertise, quality and safety" along with "the capacity to undertake independent practice and exercise leadership" as well as "commitment to keep pace with advancing knowledge and with

560-705: The International Astronomical Union . Small craters of special interest (for example, visited by lunar missions) receive human first names (Robert, José, Louise etc.). One of the biggest lunar craters, Apollo , is named after Apollo missions . Many smaller craters inside and near it bear the names of deceased American astronauts, and many craters inside and near Mare Moscoviense bear the names of deceased Soviet cosmonauts. Besides this, in 1970 twelve craters were named after twelve living astronauts (6 Soviet and 6 American). The majority of named lunar craters are satellite craters : their names consist of

600-539: The Islamic medieval period , which saw the development of scientific methodology emphasising experimentation , such as the work of Ibn al-Haytham (Alhazen) in the 11th century. The modern scientific worldview and the bulk of physics education can be said to flow from the scientific revolution in Europe, starting with the work of astronomer Nicolaus Copernicus leading to the physics of Galileo Galilei and Johannes Kepler in

640-471: The Liverpool Institute and proceeded to Liverpool University with a County Council Scholarship and a Bibby Scholarship. Barkla initially studied Mathematics but later specialised in Physics under Sir Oliver Lodge . During the absence of Oliver Lodge due to ill health, Barkla replaced him in lectures. In 1899 Barkla was admitted to Trinity College, Cambridge , with an 1851 Research Fellowship from

680-891: The Nobel Prize in Physics in 1917. He was also awarded the Hughes Medal of the British Royal Society that same year. Barkla proposed the J-phenomenon as a hypothetical form of X-ray behaviour similar to X-ray fluorescence . However, other scientists were not persuaded that this was a different mechanism from other known effects such as Compton scattering , so the theory was not successful. From 1922 to 1938 he lived at Hermitage of Braid in south-west Edinburgh. He died at 12 noon on 23 October 1944 at his home "Braidwood" in Corrennie Gardens in Edinburgh. A religious man, Barkla

720-685: The Royal Commission for the Exhibition of 1851 , to work in the Cavendish Laboratory under the physicist J. J. Thomson (discoverer of the electron). During his first two years at Cambridge, under the directions of Thomson, Barkla studied the velocity of electromagnetic waves along wires of different widths and materials. After a year and a half at Trinity College, Cambridge, his love of music led him to transfer to King's College, Cambridge , in order to sing in their chapel choir . Barkla's voice

760-404: The University of Edinburgh in 1913, a position he held until his death. Barkla made significant progress in developing and refining the laws of X-ray scattering, X-ray spectroscopy , the principles governing the transmission of X-rays through matter, and especially the principles of the excitation of secondary X-rays. For his discovery of the characteristic X-rays of elements, Barkla was awarded

800-519: The lunar south pole . However, it is believed that many of the lunar maria were formed by giant impacts, with the resulting depression filled by upwelling lava . Craters typically will have some or all of the following features: There are at least 1.3 million craters larger than 1 km (0.62 mi) in diameter; of these, 83,000 are greater than 5 km (3 mi) in diameter, and 6,972 are greater than 20 km (12 mi) in diameter. Smaller craters than this are being regularly formed, with

840-579: The 19th century. Many physicists contributed to the development of quantum mechanics in the early-to-mid 20th century. New knowledge in the early 21st century includes a large increase in understanding physical cosmology . The broad and general study of nature, natural philosophy , was divided into several fields in the 19th century, when the concept of "science" received its modern shape. Specific categories emerged, such as "biology" and "biologist", "physics" and "physicist", "chemistry" and "chemist", among other technical fields and titles. The term physicist

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880-505: The Moon's craters were mostly of impact origin. Around 1960, Gene Shoemaker revived the idea. According to David H. Levy , Shoemaker "saw the craters on the Moon as logical impact sites that were formed not gradually, in eons , but explosively, in seconds." Evidence collected during the Apollo Project and from uncrewed spacecraft of the same period proved conclusively that meteoric impact, or impact by asteroids for larger craters,

920-611: The U.S. began to convert the Wood and Andersson lunar impact-crater database into digital format. Barlow is also creating a new lunar impact crater database similar to Wood and Andersson's, except hers will include all impact craters greater than or equal to five kilometers in diameter and is based on the Clementine spacecraft's images of the lunar surface. The Moon Zoo project within the Zooniverse program aimed to use citizen scientists to map

960-399: The approach to problem-solving) developed in your education or experience as a physicist, in all cases regardless of whether the experience is in academia, industry, government, or elsewhere. Management of physics-related work qualifies, and so does appropriate graduate student work. The South African Institute of Physics also delivers a certification of Professional Physicist (Pr.Phys). At

1000-408: The craters were caused by projectile bombardment from space, the other, that they were the products of subterranean lunar volcanism . Scientific opinion as to the origin of craters swung back and forth over the ensuing centuries. The competing theories were: Grove Karl Gilbert suggested in 1893 that the Moon's craters were formed by large asteroid impacts. Ralph Baldwin in 1949 wrote that

1040-517: The designation of Professional Engineer (P. Eng.). This designation was unveiled at the CAP congress in 1999 and already more than 200 people carry this distinction. To get the certification, at minimum proof of honours bachelor or higher degree in physics or a closely related discipline must be provided. Also, the physicist must have completed, or be about to complete, three years of recent physics-related work experience after graduation. And, unless exempted,

1080-455: The early 1600s. The work on mechanics , along with a mathematical treatment of physical systems, was further developed by Christiaan Huygens and culminated in Newton's laws of motion and Newton's law of universal gravitation by the end of the 17th century. The experimental discoveries of Faraday and the theory of Maxwell's equations of electromagnetism were developmental high points during

1120-735: The increasing expectations and requirements for which any profession must take responsibility". Chartered Physicist is considered to be equal in status to Chartered Engineer, which the IoP also awards as a member of the Engineering Council UK, and other chartered statuses in the UK. It is also considered a "regulated profession" under the European professional qualification directives. The Canadian Association of Physicists can appoint an official designation called Professional Physicist ( P. Phys. ), similar to

1160-1172: The largest employer being the last. Physicists in academia or government labs tend to have titles such as Assistants, Professors , Sr./Jr. Scientist, or postdocs . As per the American Institute of Physics , some 20% of new physics Ph.D.s holds jobs in engineering development programs, while 14% turn to computer software and about 11% are in business/education. A majority of physicists employed apply their skills and training to interdisciplinary sectors (e.g. finance ). Job titles for graduate physicists include Agricultural Scientist , Air Traffic Controller , Biophysicist , Computer Programmer , Electrical Engineer , Environmental Analyst , Geophysicist , Medical Physicist , Meteorologist , Oceanographer , Physics Teacher / Professor / Researcher , Research Scientist , Reactor Physicist , Engineering Physicist , Satellite Missions Analyst, Science Writer , Stratigrapher , Software Engineer , Systems Engineer , Microelectronics Engineer , Radar Developer, Technical Consultant, etc. The majority of Physics terminal bachelor's degree holders are employed in

1200-406: The name of a nearby named crater and a capital letter (for example, Copernicus A , Copernicus B , Copernicus C and so on). Lunar crater chains are usually named after a nearby crater. Their Latin names contain the word Catena ("chain"). For example, Catena Davy is situated near the crater Davy . The red marker on these images illustrates the location of the named crater feature on

1240-433: The private sector. Other fields are academia, government and military service, nonprofit entities, labs and teaching. Typical duties of physicists with master's and doctoral degrees working in their domain involve research, observation and analysis, data preparation, instrumentation, design and development of industrial or medical equipment, computing and software development, etc. The highest honor awarded to physicists

Charles Glover Barkla - Misplaced Pages Continue

1280-422: The question of whether X-rays were indeed a type of electromagnetic radiation as many physicists suspected, because Lionel Wilberforce proposed to use these secondary rays to generate tertiary ones and prove the existence of polarization by rotating the detecting part of his experimental apparatus. Tertiary radiation was too feeble to measure, so Barkla assembled a slightly different setup. Using his new setup, he

1320-538: The results into five broad categories. These successfully accounted for about 99% of all lunar impact craters. The LPC Crater Types were as follows: Beyond a couple of hundred kilometers in diameter, the central peak of the TYC class disappear and they are classed as basins . Large craters, similar in size to maria, but without (or with a small amount of) dark lava filling, are sometimes called thalassoids. Beginning in 2009 Nadine G. Barlow of Northern Arizona University ,

1360-484: The size and shape of as many craters as possible using data from the NASA Lunar Reconnaissance Orbiter . However, it has since been retired. Craters constitute 95% of all named lunar features. Usually they are named after deceased scientists and other explorers. This tradition comes from Giovanni Battista Riccioli , who started it in 1651. Since 1919, assignment of these names is regulated by

1400-554: Was a Methodist and considered his work to be "part of the quest for God, the Creator". The lunar crater Barkla was named in the honour of Charles Barkla. A plaque exists on Barkla's house at Hermitage of Braid in Edinburgh. A commemorative plaque has been installed in the vicinity of the Canongate, near the Faculty of Education Buildings, at the University of Edinburgh . Additionally,

1440-696: Was able to prove that X-rays can indeed be polarized and are therefore electromagnetic. He published a brief summary of his findings in Nature in March 1904 and a more detailed account in the Philosophical Transactions of the Royal Society in 1905. In 1913, after having worked at the Universities of Cambridge, Liverpool, and King's College London , Barkla was appointed as a Professor of Natural Philosophy at

1480-683: Was adopted from the Greek word for "vessel" ( Κρατήρ , a Greek vessel used to mix wine and water). Galileo built his first telescope in late 1609, and turned it to the Moon for the first time on November 30, 1609. He discovered that, contrary to general opinion at that time, the Moon was not a perfect sphere, but had both mountains and cup-like depressions. These were named craters by Johann Hieronymus Schröter (1791), extending its previous use with volcanoes . Robert Hooke in Micrographia (1665) proposed two hypotheses for lunar crater formation: one, that

1520-738: Was coined by William Whewell (also the originator of the term "scientist") in his 1840 book The Philosophy of the Inductive Sciences . A standard undergraduate physics curriculum consists of classical mechanics , electricity and magnetism , non-relativistic quantum mechanics , optics , statistical mechanics and thermodynamics , and laboratory experience. Physics students also need training in mathematics ( calculus , differential equations , linear algebra , complex analysis , etc.), and in computer science . Any physics-oriented career position requires at least an undergraduate degree in physics or applied physics, while career options widen with

1560-410: Was of remarkable beauty and his solo performances were always fully attended. He completed his Bachelor of Arts degree in 1903, and then his Master of Arts degree in 1907. He married Mary Esther Cowell in the same year, with whom he had two sons and one daughter. In 1903 he studied secondary X-rays from gases radiated by other X-rays, developing a new experimental setup. This topic was relevant to

1600-413: Was the origin of almost all lunar craters, and by implication, most craters on other bodies as well. The formation of new craters is studied in the lunar impact monitoring program at NASA . The biggest recorded crater was caused by an impact recorded on March 17, 2013. Visible to the naked eye , the impact is believed to be from an approximately 40 kg (88 lb) meteoroid striking the surface at

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