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Kent Ford (astronomer)
William Kent Ford Jr. (April 8, 1931 – June 18, 2023) was an American astronomer involved with the discovery of dark matter. He worked with scientist Vera Rubin, who used his advanced spectrometer in her studies of space and matter. Using this spectrometer to analyze the Doppler shifts of galaxies as a function of distance from their centers, the pair was able to demonstrate that dark matter existed and was widespread. Ford received the 1985 James Craig Watson Medal for his work on image enhancement and galactic dynamics. Ford died on June 18, 2023, at the age of 92. Work Imaging tube development Starting in 1955, when he was hired at the Carnegie Institute's Department of Terrestrial Magnetism, Ford worked on improving the electrostatic photomultiplier tube and developing it as an instrument for scientific work, and went on to pioneer the application of photomultiplier tubes as a sensitive focal-plane detector for astronomical applications, resulting in the "Carnegie Image Tu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clifton Forge, Virginia
Clifton Forge is a town in Alleghany County, Virginia, United States which is part of the greater Roanoke Region. The population was 3,555 at the 2020 census. The Jackson River flows through the town, which as a result was once known as Jackson's River Station. Clifton Forge was an independent city during the 2000 census. However, in 2001, Clifton Forge gave up its city status and reverted to a town. In previous decades, the railroad was a major employer. Clifton Forge is known for its mountain views and clear streams. History Clifton Forge Commercial Historic District, Clifton Forge Residential Historic District, Clifton Furnace, Jefferson School, and Longdale Furnace Historic District are listed on the National Register of Historic Places. Geography Clifton Forge is located at (37.819801, -79.823584). According to the United States Census Bureau, the town had a total area of , all land. Portions of the town were built upon a bridge, elevating the town above a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnegie Institution For Science
The Carnegie Institution for Science, also known as Carnegie Science and the Carnegie Institution of Washington, is an organization established to fund and perform scientific research in the United States. This institution is headquartered in Washington, D.C. , the Institution's endowment was valued at $926.9 million. In 2018, the expenses for scientific programs and administration were $96.6 million. American astrophysicist John Mulchaey is the current president of the institution. Name More than 20 independent organizations were established through the philanthropy of Andrew Carnegie and feature his surname. In 2024, the "Carnegie Institution for Science" officially adopted the name "Carnegie Science", a name which has been used informally since 2007 when they first changed the name from "Carnegie Institution of Washington" to "Carnegie Institution for Science". History It is proposed to found in the city of Washington, an institution which ... shall in the broad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1931 Births
Events January * January 2 – South Dakota native Ernest Lawrence invents the cyclotron, used to accelerate particles to study nuclear physics. * January 4 – German pilot Elly Beinhorn begins her flight to Africa. * January 22 – Sir Isaac Isaacs is sworn in as the first Australian-born Governor-General of Australia. * January 25 – Mohandas Gandhi is again released from imprisonment in India. * January 27 – Pierre Laval forms a government in France. * January 30 – Charlie Chaplin comedy drama film ''City Lights'' receives its public premiere at the Los Angeles Theater with Albert Einstein as guest of honor. Contrary to the current trend in cinema, it is a silent film, but with a score by Chaplin. Critically and commercially successful from the start, it will place consistently in lists of films considered the best of all time. February * February 4 – Soviet leader Joseph Stalin gives a speech calling for rapid industrialization, arguing that only strong indus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Museum Of Natural History
The American Museum of Natural History (AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. Located in Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 21 interconnected buildings housing 45 permanent exhibition halls, in addition to a planetarium and a library. The museum collections contain about 32 million specimens of plants, animals, fungi, fossils, minerals, rocks, meteorites, human remains, and human cultural artifacts, as well as specialized collections for frozen tissue and genomic and astrophysical data, of which only a small fraction can be displayed at any given time. The museum occupies more than . AMNH has a full-time scientific staff of 225, sponsors over 120 special field expeditions each year, and averages about five million visits annually. The AMNH is a private 501(c)(3) organization. The naturalist Albert S. Bickmore devised the idea for the American Museum of Natural History in 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubin–Ford Effect
The Rubin–Ford effect is, per Ian Ridpath's ''Dictionary of Astronomy'', an apparent rather than actual "anisotropy in the expansion of the Universe on a scale of around 100 million ight yearsas revealed by a study of the motions of a sample of spiral galaxies," as initially described by Vera Rubin, William Kent Ford Jr., and Norbert Thonnard of the Carnegie Institution of Washington, Morton S. Roberts of the National Radio Astronomy Observatory, and John A. Graham of the Cerro Tololo Inter-American Observatory, in La Serena, Chile. Specifically, their conclusion was that a sample of galaxies (referred to as ScI) was, on the whole, moving with a velocity of 885 km s−1 toward a specific astronomical position (l = 304°, b = 26°) relative to the microwave background radiation, which, because it is isotropic, provided a frame of reference for the measurement. Also available as 2002 update and in aan all retrieved December 28, 2016. The description by Rubin Rubin is both ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler's Laws Of Planetary Motion
In astronomy, Kepler's laws of planetary motion, published by Johannes Kepler in 1609 (except the third law, which was fully published in 1619), describe the orbits of planets around the Sun. These laws replaced circular orbits and epicycles in the heliocentric theory of Nicolaus Copernicus with elliptical orbits and explained how planetary velocities vary. The three laws state that: # The orbit of a planet is an ellipse with the Sun at one of the two foci. # A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. # The square of a planet's orbital period is proportional to the cube of the length of the semi-major axis of its orbit. The elliptical orbits of planets were indicated by calculations of the orbit of Mars. From this, Kepler inferred that other bodies in the Solar System, including those farther away from the Sun, also have elliptical orbits. The second law establishes that when a planet is closer to the Sun, it travels fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxy Rotation Curve
The rotation curve of a disc galaxy (also called a velocity curve) is a plot of the orbital speeds of visible stars or gas in that galaxy versus their radial distance from that galaxy's centre. It is typically rendered graphically as a plot, and the data observed from each side of a spiral galaxy are generally asymmetric, so that data from each side are averaged to create the curve. A significant discrepancy exists between the experimental curves observed, and a curve derived by applying gravity theory to the matter observed in a galaxy. Theories involving dark matter are the main postulated solutions to account for the variance. The rotational/orbital speeds of galaxies/stars do not follow the rules found in other orbital systems such as stars/planets and planets/moons that have most of their mass at the centre. Stars revolve around their galaxy's centre at equal or increasing speed over a large range of distances. In contrast, the orbital velocities of planets in planetary s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photomultiplier Tube
Photomultiplier tubes (photomultipliers or PMTs for short) are extremely sensitive detectors of light in the ultraviolet, visible light, visible, and near-infrared ranges of the electromagnetic spectrum. They are members of the class of vacuum tubes, more specifically vacuum phototubes. These detectors multiply the current produced by incident light by as much as 100 million times or 108 (i.e., 160 decibel, dB),Decibels are power ratios. Power is proportional to I2 (current squared). Thus a current gain of 108 produces a power gain of 1016, or 160 decibel, dB in multiple dynode stages, enabling (for example) individual photons to be detected when the incident flux of light is low. The combination of high Gain (electronics), gain, low Noise (electronics), noise, high frequency response or, equivalently, ultra-fast response, and large area of collection has maintained photomultipliers an essential place in Spectroscopy, low light level spectroscopy, confocal microscopy, Raman spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States National Academy Of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the National Academy of Medicine (NAM). As a national academy, new members of the organization are elected annually by current members, based on their distinguished and continuing achievements in original research. Election to the National Academy is one of the highest honors in the scientific field in the United States. Members of the National Academy of Sciences serve '' pro bono'' as "advisers to the nation" on science, engineering, and medicine. The group holds a congressional charter under Title 36 of the United States Code. Congress legislated and President Abraham Lincoln signed an Act of Congress (1863) establishing the National Academy of Sciences as an independent, trusted nongovernmental institution, created for the purpose of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virginia
Virginia, officially the Commonwealth of Virginia, is a U.S. state, state in the Southeastern United States, Southeastern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States between the East Coast of the United States, Atlantic Coast and the Appalachian Mountains. The state's List of capitals in the United States, capital is Richmond, Virginia, Richmond and its most populous city is Virginia Beach, Virginia, Virginia Beach. Its most populous subdivision is Fairfax County, Virginia, Fairfax County, part of Northern Virginia, where slightly over a third of Virginia's population of more than 8.8million live. Eastern Virginia is part of the Atlantic Plain, and the Middle Peninsula forms the mouth of the Chesapeake Bay. Central Virginia lies predominantly in the Piedmont (United States), Piedmont, the foothill region of the Blue Ridge Mountains, which cross the western and southwestern parts of the state. The fertile Shenandoah Valley fosters the state's mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Craig Watson Medal
image:Watson_medal_NAS.gif, 400px, James Craig Watson Medal The James Craig Watson Medal was established by the bequest of James Craig Watson, an astronomer the University of Michigan between 1863 and 1879, and is awarded every 1-4 years by the U.S. National Academy of Sciences for contributions to astronomy. Recipients SourcNational Academy of Sciences See also * List of astronomy awards * List of awards named after people References {{DEFAULTSORT:Watson Medal Astronomy prizes, Watson Awards established in 1887 Awards of the United States National Academy of Sciences 1887 establishments in the United States ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vera Rubin
Vera Florence Cooper Rubin (; July 23, 1928 – December 25, 2016) was an American astronomer who pioneered work on galaxy rotation rates. She uncovered the discrepancy between the predicted and observed angular motion of galaxies by studying galactic rotation curves. Her work on the galaxy rotation problem was cited by others as evidence for the existence of dark matter. Honored throughout her lifetime for her work, she received the Bruce Medal, the Gold Medal of the Royal Astronomical Society, and the National Medal of Science, among others. The Vera C. Rubin Observatory in Chile is named in her honor. Her legacy is described by ''The New York Times'' as "ushering in a Copernican-scale change" in cosmological theory. Rubin is widely regarded as having been one of the select women in science who were overlooked for the Nobel Prize on the basis of gender discrimination. Rubin spent her life advocating for women in science, and was known for her mentorship of aspiring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
