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List of Volcanic Features on Io
This is a list of named volcanic surface features on Jupiter's moon Io. These names have been approved for use by the International Astronomical Union. The features listed below represent a subset of the total known volcanic features on Io's surface with the majority currently not having an officially approved name. The names of volcanic features on Io use a combination of a name derived from mythological figures from around the world related to the Sun, fire, volcanoes, thunder, or smithing, places from the Greek mythological story of Io, Dante's Inferno, or from the name of a nearby feature on Io's surface and an approved descriptive term. The descriptive term used is based on the type of feature named and how it was first discovered. Volcanoes that were first observed as an active feature from observations of a volcanic plume fit under the category of "Eruptive Center" and do not use a descriptive term, though portions of these features may have also received names that do use a descriptive term, like Prometheus Patera or Masubi Fluctus. Lava flows use the descriptive term fluctus or the plural fluctūs, e.g. Acala Fluctus. Volcanic depressions use the term patera or the plural paterae, e.g. Ah Peku Patera. The term has also become the generic term for referring to these structures. Small shield volcanoes use the term tholus or the plural tholi, e.g. Inachus Tholus. Finally, channels carved by volcanic lava flows through thermal erosion use the term vallis or the plural valles. See also the list of mountains on Io and the list of regions on Io.
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Topic Review
Space and Upper Atmosphere Research Commission
Established in its modern form on 16 September 1961 by an executive order of President of Pakistan, it is headquartered in Karachi, Sindh Province of Pakistan. Part of the Strategic Plans Division (SPD) of Pakistan Armed Forces, which is currently headquartered at the Chakalala Military District under the control of the Pakistan Air Force ; the space programmes recorded number of pioneering accomplishments in space flight during the initial years of its establishment. The country's first satellite, Badr-I, was built by the SUPARCO and launched from the Xichang Satellite Launch Center, China on July 16, 1990. However, during the meantime, the space programme suffered many setbacks, difficulties, and problems that partly slowed the progress of the space programme. The bureaucratic influence and politicization further lagged the space programme and many projects were cancelled by the superior authorities. Over the years, SUPARCO expanded and it now has several installations all over the country. It has multi-lateral and bilateral international agreements. SUPARCO has been quite dormant in recent years and also have failed to make any breakthroughs. SUPARCO's science and research is mainly focused and concentrated on understanding of the Solar system, Space weather, astrophysics, astronomical observation, climatic studies, space and telemedicine, remote sensing and the Earth observation.
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Topic Review
Photoelectrochemical Reduction of CO2
Photoelectrochemical reduction of CO2 is a chemical process whereby carbon dioxide is reduced to carbon monoxide or hydrocarbons by the energy of incident light. This process needs to be catalyzed either homogeneously or heterogeneously in order to proceed, and current research is aimed at developing these catalysts, most of which are semiconducting materials. Semiconducting catalysts provide favourable electron transfer kinetics. The feasibility of this chemical reaction was first theorised by Giacomo Luigi Ciamician, an Italian photochemist. Already in 1912 he stated that "By  using  suitable catalyzers,  it  should  be  possible  to  transform  the mixture  of  water  and  carbon dioxide into oxygen and methane, or to cause other endo-energetic processes." Motivation for research in this area is strong due to the current attention to atmospheric carbon dioxide as the reduction of carbon dioxide would be one route for removal and sequestration. Furthermore, the reduced species may prove to be a valuable feedstock for other processes. If the incident light utilized is solar in nature then this process also potentially represents energy routes which combine renewable energy with CO2 reduction.
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Topic Review
Kelvin–Stokes Theorem
The Kelvin–Stokes theorem, named after Lord Kelvin and George Stokes, also known as the Stokes' theorem, the fundamental theorem for curls or simply the curl theorem, is a theorem in vector calculus on [math]\displaystyle{ \mathbb{R}^3 }[/math]. Given a vector field, the theorem relates the integral of the curl of the vector field over some surface, to the line integral of the vector field around the boundary of the surface. If a vector field [math]\displaystyle{ \mathbf{A} = (P(x, y, z), Q(x, y, z), R(x, y, z)) }[/math] is defined in a region with smooth oriented surface [math]\displaystyle{ \Sigma }[/math] and has first order continuous partial derivatives then: where [math]\displaystyle{ \partial \Sigma }[/math] is boundary of region with smooth surface [math]\displaystyle{ \Sigma }[/math]. The above classical Kelvin-Stokes theorem can be stated in one sentence: The line integral of a vector field over a loop is equal to the flux of its curl through the enclosed surface. The Kelvin–Stokes theorem is a special case of the "generalized Stokes' theorem." In particular, a vector field on [math]\displaystyle{ \mathbb{R}^3 }[/math] can be considered as a 1-form in which case its curl is its exterior derivative, a 2-form.
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Topic Review
Night Thoughts of a Classical Physicist
Night Thoughts of a Classical Physicist is an historical novel by historian of science Russell McCormmach, published in 1982 by Harvard University Press. Set in 1918, the book explores the world of physics in the early 20th century—including the advent of modern physics and the role of physicists in World War I—through the recollections of the fictional Viktor Jakob. Jakob is an old German physicist who spent most of his career during the period of classical physics, a paradigm being confronted by the rapid and radical developments of relativistic physics in 1900s and 1910s. This conflict allows for extensive examination of the various tensions placed on Jakob by the academic environment, the German academic system, and the changing academic culture of the early 20th century. The character of Jakob, a professor at a minor German university, is an amalgam of German physicists based on archival research by McCormmach. In the novel, he recalls interactions and events, documented in extensive footnotes to genuine publications and archival sources, involving many of the well-known physicists of the late 19th and early 20th centuries. Night Thoughts, pointedly criticized for its lack of literary merit by some reviewers, was generally praised for its attempt at forging a new approach to history and historical fiction by incorporating extensive research into the text.
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Topic Review
MOST (Satellite)
The Microvariability and Oscillations of Stars telescope, better known simply as MOST, was Canada 's first space telescope. Up until nearly 10 years after its launch it was also the smallest space telescope in orbit (for which its creators nicknamed it the "Humble Space Telescope", in reference to one of the largest, the Hubble). MOST was the first spacecraft dedicated to the study of asteroseismology, subsequently followed by the now-completed CoRoT and Kepler missions. It was also the first Canadian science satellite launched since ISIS II, 32 years previously.
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Topic Review
KTHNY Theory
The KTHNY-theory describes melting of crystals in two dimensions (2D). The name is derived from the initials of the surnames of John Michael Kosterlitz, David J. Thouless, Bertrand Halperin, David R. Nelson, and A. Peter Young, who developed the theory in the 1970s. It is, beside the Ising model in 2D and the XY model in 2D, one of the few theories, which can be solved analytically and which predicts a phase transition at a temperature [math]\displaystyle{ T \gt 0 }[/math].
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Topic Review
International Space Station Maintenance
Since construction started, the International Space Station (ISS) programme has had to deal with several maintenance issues, unexpected problems and failures. These incidents have affected the assembly timeline, led to periods of reduced capabilities of the station and in some cases could have forced the crew to abandon the space station for safety reasons, had these problems not been resolved.
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Topic Review
Left-Right Asymmetry
Left-right asymmetry (LR asymmetry) refers to differences in structure (symmetry breaking) across the mediolateral (left and right) plane in animals. This plane is defined with respect to the anteroposterior and dorsoventral axes and is perpendicular to both. Because the left-right plane is not strictly an axis (as it is not established through a morphogen gradient), to create asymmetry, the left and right sides need to be patterned separately. LR asymmetry is pervasive throughout metazoans and present throughout every major lineage. Notable examples include the large and small claws of the fiddler crab, the left offset of the vertebrate heart, asymmetrical gut coiling in Drosophila melanogaster, and dextral (clockwise) and sinistral (counterclockwise) coiling of gastropods. This asymmetry can be restricted to a specific organ or feature, as in the crab claws, or be expressed throughout the entire body as in snails.
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Topic Review
Glossary of Nanotechnology
This glossary of nanotechnology is a list of definitions of terms and concepts relevant to nanotechnology, its sub-disciplines, and related fields. For more inclusive glossaries concerning related fields of science and technology, see Glossary of chemistry terms, Glossary of physics, Glossary of biology, and Glossary of engineering.
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