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Biography
Heinz Pagels
Heinz Rudolf Pagels (February 19, 1939 – July 23, 1988) was an United States physicist,[1] an adjunct professor of physics at Rockefeller University, the executive director and chief executive officer of the New York Academy of Sciences, and president of the International League for Human Rights. He wrote the popular science books The Cosmic Code (1982), Perfect Symmetry (1985), and The Dreams
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  • 02 Dec 2022
Biography
Joseph Larmor
Sir Joseph Larmor FRS FRSE DCL LLD[1] (11 July 1857 – 19 May 1942) was an Irish[2] physicist and mathematician who made innovations in the understanding of electricity, dynamics, thermodynamics, and the electron theory of matter. His most influential work was Aether and Matter, a theoretical physics book published in 1900. He was born in Magheragall in County Antrim the son of Hugh Larmor,
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  • 02 Dec 2022
Topic Review
Precursor
Precursors are characteristic wave patterns caused by dispersion of an impulse's frequency components as it propagates through a medium. Classically, precursors precede the main signal, although in certain situations they may also follow it. Precursor phenomena exist for all types of waves, as their appearance is only predicated on the prominence of dispersion effects in a given mode of wave propagation. This non-specificity has been confirmed by the observation of precursor patterns in different types of electromagnetic radiation (microwaves, visible light, and terahertz radiation) as well as in fluid surface waves and seismic waves.
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  • 02 Dec 2022
Topic Review
Solar System Model
Solar System models, especially mechanical models, called orreries, that illustrate the relative positions and motions of the planets and moons in the Solar System have been built for centuries. While they often showed relative sizes, these models were usually not built to scale. The enormous ratio of interplanetary distances to planetary diameters makes constructing a scale model of the Solar System a challenging task. As one example of the difficulty, the distance between the Earth and the Sun is almost 12,000 times the diameter of the Earth. If the smaller planets are to be easily visible to the naked eye, large outdoor spaces are generally necessary, as is some means for highlighting objects that might otherwise not be noticed from a distance. The Boston Museum of Science has placed bronze models of the planets in major public buildings, all on similar stands with interpretive labels. For example, the model of Jupiter is located in the cavernous South Station waiting area. The properly-scaled, basket-ball-sized model is 1.3 miles (2.14 km) from the model Sun which is located at the museum, graphically illustrating the immense empty space in the Solar System. The objects in such large models do not move. Traditional orreries often did move, and some used clockworks to display the relative speeds of objects accurately. These can be thought of as being correctly scaled in time, instead of distance.
  • 552
  • 01 Dec 2022
Topic Review
Bya (Unit)
A year is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars; see below. For the Gregorian calendar, the average length of the calendar year (the mean year) across the complete leap cycle of 400 years is 365.2425 days. The ISO standard ISO 80000-3, Annex C, supports the symbol a (for Latin annus) to represent a year of either 365 or 366 days. In English, the abbreviations y and yr are commonly used. In astronomy, the Julian year is a unit of time; it is defined as 365.25 days of exactly 86,400 seconds (SI base unit), totalling exactly 31,557,600 seconds in the Julian astronomical year. The word year is also used for periods loosely associated with, but not identical to, the calendar or astronomical year, such as the seasonal year, the fiscal year, the academic year, etc. Similarly, year can mean the orbital period of any planet; for example, a Martian year and a Venusian year are examples of the time a planet takes to transit one complete orbit. The term can also be used in reference to any long period or cycle, such as the Great Year.
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  • 01 Dec 2022
Biography
Peter Woit
Peter Woit (/ˈwɔɪt/; born September 11, 1957) is an American theoretical physicist. He is a Senior Lecturer in the Mathematics department at Columbia University. Woit is a critic of string theory has published a book Not Even Wrong, and writes a blog of the same name.[1] Woit graduated in 1979 from Harvard University with bachelor's and master's degrees in physics. He obtained his PhD in p
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  • 01 Dec 2022
Biography
Uschi Steigenberger
Ursula "Uschi" Steigenberger (25 April 1951 — 12 December 2018) OBE FInstP was a German condensed matter physicist and director of the ISIS neutron source. She was one of the founders of the Institute of Physics Juno Award. Steigenberger was born in Augsburg. She studied physics at the University of Würzburg, where she remained for her graduate studies. She earned a PhD in condensed matter
  • 419
  • 01 Dec 2022
Topic Review
Transactinide Element
In chemistry, transactinide elements (also, transactinides, or super-heavy elements) are the chemical elements with atomic numbers from 104 to 120. Their atomic numbers are immediately greater than those of the actinides, the heaviest of which is lawrencium (atomic number 103). Glenn T. Seaborg first proposed the actinide concept, which led to the acceptance of the actinide series. He also proposed the transactinide series ranging from element 104 to 121 and the superactinide series approximately spanning elements 122 to 153. The transactinide seaborgium was named in his honor. By definition, transactinide elements are also transuranic elements, i.e. have an atomic number greater than uranium (92). The transactinide elements all have electrons in the 6d subshell in their ground state. Except for rutherfordium and dubnium, even the longest-lasting isotopes of transactinide elements have extremely short half-lives, measured in seconds, or smaller units. The element naming controversy involved the first five or six transactinide elements. These elements thus used systematic names for many years after their discovery had been confirmed. (Usually the systematic names are replaced with permanent names proposed by the discoverers relatively shortly after a discovery has been confirmed.) Transactinides are radioactive and have only been obtained synthetically in laboratories. None of these elements has ever been collected in a macroscopic sample. Transactinide elements are all named after physicists and chemists or important locations involved in the synthesis of the elements. IUPAC defines an element to exist if its lifetime is longer than 10−14 seconds, which is the time it takes for the nucleus to form an electron cloud.
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  • 01 Dec 2022
Biography
Arkady Adamovich Brish
Arkady Adamovich Brish (May 14, 1917 – March 19, 2016) was a Soviet and Russian scientist, a designer of nuclear weapons, doctor of technical sciences, professor, Hero of Socialist Labour, Laureate of the Lenin Prize, the USSR State Prize and the RF Government Prize. Brish was born on May 14, 1917 in Minsk to a teacher's family in Belarus. In 1931–1933 he was an apprentice electrician in
  • 406
  • 01 Dec 2022
Topic Review
Mapping Imaging Spectrometer for Europa
The Mapping Imaging Spectrometer for Europa (MISE) is an imaging near infrared spectrometer on board the Europa Clipper mission to Jupiter's moon Europa. MISE will examine Europa's surface composition and relate it to the habitability of its internal water ocean.
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  • 01 Dec 2022
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