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Jesse Greenstein
Jesse Leonard Greenstein (October 15, 1909 – October 21, 2002) was an American astronomer. His parents were Maurice G. and Leah Feingold. He earned a Ph.D, with thesis advisor Donald H. Menzel, from Harvard University in 1937, having started there at age 16. Before leaving Harvard, Greenstein was involved in a project with Fred Lawrence Whipple to explain Karl Jansky's discovery of radio waves from the Milky Way and to propose a source. He began his professional career at Yerkes Observatory under Otto Struve and later went to Caltech. With Louis G. Henyey he invented a new spectrograph and a wide-field camera. He directed the Caltech astronomy program until 1972 and later did classified work on military reconnaissance satellites. With Leverett Davis, Jr, he demonstrated in 1949 that the magnetic field in our galaxy is aligned with the spiral arms. His theoretical work with Davis was based on the conclusion just reached by William A. Hiltner that the recently detected ...
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Astronomer
An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, galaxies – in either observational astronomy, observational (by analyzing the data) or theoretical astronomy. Examples of topics or fields astronomers study include planetary science, Sun, solar astronomy, the Star formation, origin or stellar evolution, evolution of stars, or the galaxy formation and evolution, formation of galaxies. A related but distinct subject is physical cosmology, which studies the Universe as a whole. Types Astronomers usually fall under either of two main types: observational astronomy, observational and theoretical astronomy, theoretical. Observational astronomers make direct observations of Astronomical object, celestial objects and analyze the data. In contrast, theoretical astronomers create and investigate C ...
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Chemical Element
A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species. Unlike chemical compounds, chemical elements cannot be broken down into simpler substances by any chemical reaction. The number of protons in the nucleus is the defining property of an element, and is referred to as its atomic number (represented by the symbol ''Z'') – all atoms with the same atomic number are atoms of the same element. Almost all of the baryonic matter of the universe is composed of chemical elements (among rare exceptions are neutron stars). When different elements undergo chemical reactions, atoms are rearranged into new compounds held together by chemical bonds. Only a minority of elements, such as silver and gold, are found uncombined as relatively pure native element minerals. Nearly all other naturally occurring elements occur in the Earth as compounds or mixtures. Air is primarily a mixture o ...
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American Academy Of Arts And Sciences
The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other Founding Fathers of the United States. It is headquartered in Cambridge, Massachusetts. Membership in the academy is achieved through a thorough petition, review, and election process. The academy's quarterly journal, ''Dædalus'', is published by MIT Press on behalf of the academy. The academy also conducts multidisciplinary public policy research. History The Academy was established by the Massachusetts legislature on May 4, 1780, charted in order "to cultivate every art and science which may tend to advance the interest, honor, dignity, and happiness of a free, independent, and virtuous people." The sixty-two incorporating fellows represented varying interests and high standing in the political, professional, and commercial secto ...
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American Academy Of Achievement
The American Academy of Achievement, colloquially known as the Academy of Achievement, is a non-profit educational organization that recognizes some of the highest achieving individuals in diverse fields and gives them the opportunity to meet one another. The academy also brings together the leaders with promising graduate students for mentorship. The academy hosts an International Achievement Summit, which ends with an awards ceremony, during which new members are inducted into the academy. History Founded in 1961 by ''Sports Illustrated'' and ''LIFE'' magazine photographer Brian Reynolds, the Academy of Achievement recognizes the highest achievers in public service, business, science and exploration, sports and the arts. Reynolds established the academy after he realized that the famous people he photographed from different fields did not usually have the opportunity to interact with one another. The organization was described in a 1989 ''San Francisco Chronicle'' artic ...
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Academy Of Achievement
The American Academy of Achievement, colloquially known as the Academy of Achievement, is a non-profit educational organization that recognizes some of the highest achieving individuals in diverse fields and gives them the opportunity to meet one another. The academy also brings together the leaders with promising graduate students for mentorship. The academy hosts an International Achievement Summit, which ends with an awards ceremony, during which new members are inducted into the academy. History Founded in 1961 by ''Sports Illustrated'' and ''LIFE'' magazine photographer Brian Reynolds, the Academy of Achievement recognizes the highest achievers in public service, business, science and exploration, sports and the arts. Reynolds established the academy after he realized that the famous people he photographed from different fields did not usually have the opportunity to interact with one another. The organization was described in a 1989 ''San Francisco Chronicle'' artic ...
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Gold Medal Of The Royal Astronomical Society
The Gold Medal of the Royal Astronomical Society is the highest award given by the Royal Astronomical Society (RAS). The RAS Council have "complete freedom as to the grounds on which it is awarded" and it can be awarded for any reason. Past awards have been given for "outstanding personal researches in the fields of astronomy and geophysics" as well as general contributions to astronomy and geophysics "that may be made through leadership in research programmes, through education and through scientific administration". It has been awarded both for research that has taken a lifetime (it has most frequently been given to recognise an extraordinary lifetime achievement), and for specific pieces of research. History The RAS was founded in 1820 and the first Gold Medals were awarded in 1824. Silver medals were also awarded in 1824 and 1827, but that practice was quickly abandoned, instead the RAS established other awards. In the early years, more than one medal was often awarded in a ...
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Bruce Medal
The Catherine Wolfe Bruce Gold Medal is awarded every year by the Astronomical Society of the Pacific for outstanding lifetime contributions to astronomy. It is named after Catherine Wolfe Bruce, an American patroness of astronomy, and was first awarded in 1898. List of Bruce Medalists SourceAstronomical Society of the Pacific * 1898 – Simon Newcomb * 1899 – Arthur Auwers * 1900 – David Gill * 1902 – Giovanni V. Schiaparelli * 1904 – William Huggins * 1906 – Hermann Carl Vogel * 1908 – Edward C. Pickering * 1909 – George William Hill * 1911 – Henri Poincaré * 1913 – Jacobus C. Kapteyn * 1914 – Oskar Backlund * 1915 – William Wallace Campbell * 1916 – George Ellery Hale * 1917 – Edward Emerson Barnard * 1920 – Ernest W. Brown * 1921 – Henri A. Deslandres * 1922 – Frank W. Dyson * 1923 – Benjamin Baillaud * 1924 – Arthur Stanley Eddington * 1925 – Henry Norris Russell * 1926 – Robert G. Aitken * 1927 – Herbert Hall Turner * 19 ...
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American Astronomical Society
The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC. The primary objective of the AAS is to promote the advancement of astronomy and closely related branches of science, while the secondary purpose includes enhancing astronomy education and providing a political voice for its members through lobbying and grassroots activities. Its current mission is to enhance and share humanity's scientific understanding of the universe as a diverse and inclusive astronomical community. History The society was founded in 1899 through the efforts of George Ellery Hale. The constitution of the group was written by Hale, George Comstock, Edward Morley, Simon Newcomb and Edward Charles Pickering. These men, plus four others, were the first Executive Council of the society; Newcomb was the first president. The initial membership was 114. The AAS name of the so ...
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Henry Norris Russell Lectureship
The Henry Norris Russell Lectureship is awarded each year by the American Astronomical Society in recognition of a lifetime of excellence in astronomical research. The idea for the lectureship came from then society President Harlow Shapley in 1945, who led the fund raising drive to collect $10,000 from the membership. One of the major contributors was the Mexican Ambassador to the United States, as Russell had been an important representative at the dedication ceremony for the Mexican National Observatory. The goal was reached in December 1946, using not a little amount of coercive language by Shapley. The first Russell lecturer was, naturally, fellow American astronomer Henry Norris Russell, for whom the award is named. Russell gave a lecture titled "The Royal Road of Eclipses" concerning eclipsing binary stars. Previous lecturers This list of lecturers is from the American Astronomical Society's website. See also * List of astronomy awards This list of astronomy awards is a ...
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Palomar Observatory
Palomar Observatory is an astronomical research observatory in San Diego County, California, United States, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observatory is granted to Caltech and its research partners, which include the Jet Propulsion Laboratory (JPL), Yale University, and the National Optical Observatories of China. The observatory operates several telescopes, including the Hale Telescope, the Samuel Oschin Telescope (dedicated to the Zwicky Transient Facility, ZTF), the Palomar Telescope, and the Gattini-IR telescope. Decommissioned instruments include the Palomar Testbed Interferometer and the first telescopes at the observatory, an Schmidt camera from 1936. History Hale's vision for large telescopes and Palomar Observatory Astronomer George Ellery Hale, whose vision created the Palomar Observatory, built the world's largest telescope four times in succession. He publishe ...
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Redshifts
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in frequency and energy, is known as a negative redshift, or blueshift. The terms derive from the colours red and blue which form the extremes of the visible light spectrum. In astronomy and cosmology, the three main causes of electromagnetic redshift are # The radiation travels between objects which are moving apart (" relativistic" redshift, an example of the relativistic Doppler effect) #The radiation travels towards an object in a weaker gravitational potential, i.e. towards an object in less strongly curved (flatter) spacetime (gravitational redshift) #The radiation travels through expanding space ( cosmological redshift). The observation that all sufficiently distant light sources show redshift corresponding to their distance from Ear ...
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3C 273
3C 273 is a quasar located in the constellation of Virgo (constellation), Virgo. It was the first quasar ever to be identified. It is the optically brightest quasar in the sky from Earth (apparent magnitude, m ~12.9), and one of the closest with a redshift, ''z'', of 0.158. A luminosity distance of DL = may be calculated from ''z''. It is also one of the most luminous quasars known, with an absolute magnitude of −26.7, meaning that if it were only as distant as Pollux (star), Pollux (~10 parsecs) it would Apparent magnitude, appear nearly as bright in the sky as the Sun. Since the Sun's absolute magnitude is 4.83, it means that the quasar is over 4 trillion times more luminosity, luminous than Solar luminosity, the Sun at visible wavelengths. The mass of its central black hole has been measured to be 886 ± 187 million solar masses through broad emission-line reverberation mapping. Large-scale jet The quasar has a large-scale visible astrophysical jet, jet, which measures ~ lo ...
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