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EUVE
The Extreme Ultraviolet Explorer (EUVE or Explorer 67) was a NASA space telescope for ultraviolet astronomy. EUVE was a part of NASA's Explorer spacecraft series. Launched on 7 June 1992. With instruments for ultraviolet (UV) radiation between wavelengths of 7 and 76 nm (equivalent to 0.016-0.163 keV in energy), the EUVE was the first satellite mission especially for the short-wave ultraviolet range. The satellite compiled an all-sky survey of 801 astronomical targets before being decommissioned on 31 January 2001. Mission The Extreme-Ultraviolet Explorer (EUVE) was a spinning spacecraft designed to rotate about the Earth/Sun line. EUVE was a part of NASA's Explorer spacecraft series, and designed to operate in the extreme ultraviolet (EUV) range of the spectrum, from 70 to 760 Ångström (Å). This spacecraft's objective was to carry out a full-sky survey, and subsequently, a deep-survey and pointed observations. Science objectives included discovering and studying UV ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultraviolet Astronomy
Ultraviolet astronomy is the observation of electromagnetic radiation at ultraviolet wavelengths between approximately 10 and 320 nanometres; shorter wavelengths—higher energy photons—are studied by X-ray astronomy and gamma-ray astronomy. Ultraviolet light is not visible to the human eye. Most of the light at these wavelengths is absorbed by the Earth's atmosphere, so observations at these wavelengths must be performed from the upper atmosphere or from space. Overview Ultraviolet line spectrum measurements (spectroscopy) are used to discern the chemical composition, densities, and temperatures of the interstellar medium, and the temperature and composition of hot young stars. UV observations can also provide essential information about the evolution of galaxies. They can be used to discern the presence of a hot white dwarf or main sequence companion in orbit around a cooler star. The ultraviolet universe looks quite different from the familiar stars and galaxies se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultraviolet
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionize atoms, it can cause chemical reactions and causes many substances to glow or fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Short-wave ultraviolet light damages DNA and sterilizes surfaces with which it comes into contac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultraviolet Astronomy
Ultraviolet astronomy is the observation of electromagnetic radiation at ultraviolet wavelengths between approximately 10 and 320 nanometres; shorter wavelengths—higher energy photons—are studied by X-ray astronomy and gamma-ray astronomy. Ultraviolet light is not visible to the human eye. Most of the light at these wavelengths is absorbed by the Earth's atmosphere, so observations at these wavelengths must be performed from the upper atmosphere or from space. Overview Ultraviolet line spectrum measurements (spectroscopy) are used to discern the chemical composition, densities, and temperatures of the interstellar medium, and the temperature and composition of hot young stars. UV observations can also provide essential information about the evolution of galaxies. They can be used to discern the presence of a hot white dwarf or main sequence companion in orbit around a cooler star. The ultraviolet universe looks quite different from the familiar stars and galaxies se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multi-mission Modular Spacecraft
Multi-mission Modular Spacecraft, also known as the MMS, was originally designed by NASA to serve the largest array of functions for the space program possible to decrease the cost of space missions. It was designed to operate in four distinct areas of missions. The MMS began development about a decade before it became implemented in the 1980s and 1990s. The basic MMS was made up of three different modules. They include the altitude control, communications and data handling, and the power subsystems. The idea of a modular system serving many purposes was the pioneer of the leading systems within the space technology ecosystem today as it has left a lasting legacy. The MMS was intended to be "Shuttle compatible", i.e. recoverable/serviceable by the Space Shuttle orbiter. Missions It was used for: * Solar Maximum Mission (SMM), 1980 * Landsat 4, 1982 * Landsat 5, 1984 * Upper Atmosphere Research Satellite (UARS), 1991 * Extreme Ultraviolet Explorer (EUVE), 1992 * TOPEX/Poseidon, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Sciences Laboratory
The Space Sciences Laboratory (SSL) is an Organized Research Unit (ORU) of the University of California, Berkeley. Founded in 1959, the laboratory is located in the Berkeley Hills above the university campus. It has developed and continues to develop many projects in the space sciences, including the search for extraterrestrial life ( SETI@home). History The Space Sciences Laboratory (SSL) at Berkeley, California was initiated in 1958 by a committee of faculty members who recognized that emerging rocket and satellite technology opened up new investigative realms for the physical, biological, and engineering sciences. The committee, chaired first by Professor Otto Struve of the Department of Astronomy and subsequently by Professor Edward Teller of the Department of Physics and the Lawrence Radiation Laboratory, explored with faculty members the opportunities associated with space research as well as the impact of rapidly escalating national space exploration programs ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angle Of Incidence (optics)
The angle of incidence, in geometric optics, is the angle between a ray incident on a surface and the line perpendicular (at 90 degree angle) to the surface at the point of incidence, called the normal. The ray can be formed by any waves, such as optical, acoustic, microwave, and X-ray. In the figure below, the line representing a ray makes an angle θ with the normal (dotted line). The angle of incidence at which light is first totally internally reflected is known as the critical angle. The angle of reflection and angle of refraction are other angles related to beams. In computer graphics and geography, the angle of incidence is also known as the illumination angle of a surface with a light source, such as the Earth's surface and the Sun. It can also be equivalently described as the angle between the tangent plane of the surface and another plane at right angles to the light rays. This means that the illumination angle of a certain point on Earth's surface is 0° if the S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolter Telescope
A Wolter telescope is a telescope for X-rays that only uses grazing incidence optics – mirrors that reflect X-rays at very shallow angles. Problems with conventional telescope designs Conventional telescope designs require reflection or refraction in a manner that does not work well for X-rays. Visible light optical systems use either lenses or mirrors aligned for nearly normal incidence – that is, the light waves travel nearly perpendicular to the reflecting or refracting surface. Conventional mirror telescopes work poorly with X-rays, since X-rays that strike mirror surfaces nearly perpendicularly are either transmitted or absorbed – not reflected. Lenses for visible light are made of transparent materials with an index of refraction substantially different from 1, but all known X-ray-transparent materials have index of refraction essentially the same as 1, so X-ray lenses are not practical. X-ray mirror telescope design X-ray mirrors can be built, but only if the angle f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectroscopy
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter waves and acoustic waves can also be considered forms of radiative energy, and recently gravitational waves have been associated with a spectral signature in the context of the Laser Interferometer Gravitational-Wave Observatory (LIGO) In simpler terms, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Historically, spectroscopy originated as the study of the wavelength dependence of the absorption by gas phase matter of visible light dispersed by a prism. Spectroscopy, primarily in the electromagnetic spectrum, is a fundamental exploratory tool in the fields of astronomy, chemistry, materials science, and physics, allowing the composition, physical structure an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstellar Medium
In astronomy, the interstellar medium is the matter and radiation that exist in the space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, as well as dust and cosmic rays. It fills interstellar space and blends smoothly into the surrounding intergalactic space. The energy that occupies the same volume, in the form of electromagnetic radiation, is the interstellar radiation field. The interstellar medium is composed of multiple phases distinguished by whether matter is ionic, atomic, or molecular, and the temperature and density of the matter. The interstellar medium is composed, primarily, of hydrogen, followed by helium with trace amounts of carbon, oxygen, and nitrogen. The thermal pressures of these phases are in rough equilibrium with one another. Magnetic fields and turbulent motions also provide pressure in the ISM, and are typically more important, dynamically, than the thermal pressure is. In the interstellar medium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronal Star
Coronal may refer to: * a nuptial crown * anything relating to a corona * Coronal plane, an anatomical term of location * The coronal direction on a tooth * Coronal consonant, a consonant that is articulated with the front part of the tongue * Coronal stop A coronal stop is a stop consonant articulated with the front part of the tongue (whence " coronal"). Depending on the precise place of articulation, several types can be distinguished: * Dental stops, articulated with the tongue touching the upper ..., a type of stop consonant * Coronal loop, a structure on the surface of the Sun {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
