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Loyal Blaine Aldrich
Loyal Blaine Aldrich (November 20, 1884 – February 11, 1965) was an American astrophysicist and astronomer of the Smithsonian Institution. Upon graduation from the University of Wisconsin in 1907, Aldrich became a Smithsonian Astrophysical Observatory assistant to Charles Greeley Abbot. The observatory conducted astrophysical research on solar radiation and the amount of energy from the sun that strikes the outer edge of the earth's atmosphere. Abbot became director of the observatory in 1907 and established solar observing stations in the United States, South America, and Africa to carry out research on solar radiation. Aldrich became director of the observatory from 1942 to 1955. Harvard University astronomy department chairman Fred Lawrence Whipple became director of the observatory when Aldrich retired. Family Aldrich married Elizabeth Stanley (born October 9, 1896). Their son, Stanley Loyal Aldrich, assisted his father operating the observing station in the Chile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wisconsin
Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. The bulk of Wisconsin's population live in areas situated along the shores of Lake Michigan. The largest city, Milwaukee, anchors its largest metropolitan area, followed by Green Bay and Kenosha, the third- and fourth-most-populated Wisconsin cities respectively. The state capital, Madison, is currently the second-most-populated and fastest-growing city in the state. Wisconsin is divided into 72 counties and as of the 2020 census had a population of nearly 5.9 million. Wisconsin's geography is diverse, having been greatly impacted by glaciers during the Ice Age with the exception of the Driftless Area. The Northern Highland and Western Upland along wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1884 Births
Events January–March * January 4 – The Fabian Society is founded in London. * January 5 – Gilbert and Sullivan's ''Princess Ida'' premières at the Savoy Theatre, London. * January 18 – Dr. William Price attempts to cremate his dead baby son, Iesu Grist, in Wales. Later tried and acquitted on the grounds that cremation is not contrary to English law, he is thus able to carry out the ceremony (the first in the United Kingdom in modern times) on March 14, setting a legal precedent. * February 1 – ''A New English Dictionary on historical principles, part 1'' (edited by James A. H. Murray), the first fascicle of what will become ''The Oxford English Dictionary'', is published in England. * February 5 – Derby County Football Club is founded in England. * March 13 – The siege of Khartoum, Sudan, begins (ends on January 26, 1885). * March 28 – Prince Leopold, the youngest son and the eighth child of Queen Victoria and Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrheliometer
A pyrheliometer is an instrument for measurement of direct beam solar irradiance. Sunlight enters the instrument through a window and is directed onto a thermopile which converts heat to an electrical signal that can be recorded. The signal voltage is converted via a formula to measure watts per square metre. Standards Pyrheliometer measurement specifications are subject to International Organization for Standardization (ISO) and World Meteorological Organization (WMO) standards. Comparisons between pyrheliometers for intercalibration are carried out regularly to measure the amount of solar energy received. The aim of the International Pyrheliometer Comparisons, which take place every 5 years at the World Radiation Centre in Davos, is to ensure the world-wide transfer of the World Radiometric Reference. During this event, all participants bring their instruments, solar-tracking and data acquisition systems to Davos to conduct simultaneous solar radiation measurements with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may compose the droplets and crystals. On Earth, clouds are formed as a result of saturation of the air when it is cooled to its dew point, or when it gains sufficient moisture (usually in the form of water vapor) from an adjacent source to raise the dew point to the ambient temperature. They are seen in the Earth's homosphere, which includes the troposphere, stratosphere, and mesosphere. Nephology is the science of clouds, which is undertaken in the cloud physics branch of meteorology. There are two methods of naming clouds in their respective layers of the homosphere, Latin and common name. Genus types in the troposphere, the atmospheric layer closest to Earth's surface, have Latin names because of the universal adoption of Luke Howard's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eclipse
An eclipse is an astronomical event that occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three celestial objects is known as a syzygy. Apart from syzygy, the term eclipse is also used when a spacecraft reaches a position where it can observe two celestial bodies so aligned. An eclipse is the result of either an occultation (completely hidden) or a transit (partially hidden). The term eclipse is most often used to describe either a solar eclipse, when the Moon's shadow crosses the Earth's surface, or a lunar eclipse, when the Moon moves into the Earth's shadow. However, it can also refer to such events beyond the Earth–Moon system: for example, a planet moving into the shadow cast by one of its moons, a moon passing into the shadow cast by its host planet, or a moon passing into the shadow of another moon. A binary star system can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyranometer
A pyranometer is a type of actinometer used for measuring solar irradiance on a planar surface and it is designed to measure the solar radiation flux density (W/m2) from the hemisphere above within a wavelength range 0.3 μm to 3 μm. The name pyranometer stems from the Greek words ''πῦρ'' (''pyr''), meaning "fire", and ''ἄνω'' (''ano''), meaning "above, sky". A typical pyranometer does not require any power to operate. However, recent technical development includes use of electronics in pyranometers, which do require (low) external power. Explanation The solar radiation spectrum that reaches earth's surface extends its wavelength approximately from 300 nm to 2800 nm. Depending on the type of pyranometer used, irradiance measurements with different degrees of spectral sensitivity will be obtained. To make a measurement of irradiance, it is required by definition that the response to "beam" radiation varies with the cosine of the angle of incidence. This ensure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WorldCat
WorldCat is a union catalog that itemizes the collections of tens of thousands of institutions (mostly libraries), in many countries, that are current or past members of the OCLC global cooperative. It is operated by OCLC, Inc. Many of the OCLC member libraries collectively maintain WorldCat's database, the world's largest bibliographic database. The database includes other information sources in addition to member library collections. OCLC makes WorldCat itself available free to libraries, but the catalog is the foundation for other subscription OCLC services (such as resource sharing and collection management). WorldCat is used by librarians for cataloging and research and by the general public. , WorldCat contained over 540 million bibliographic records in 483 languages, representing over 3 billion physical and digital library assets, and the WorldCat persons dataset (Data mining, mined from WorldCat) included over 100 million people. History OCLC OCLC, Inc., doing bus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voltameter
A voltameter or coulometer is a scientific instrument used for measuring electric charge (quantity of electricity) through electrolytic action. The SI unit of electric charge is the coulomb. The voltameter should not be confused with a voltmeter, which measures electric potential. The SI unit for electric potential is the volt. Types of voltameter The voltameter is an electrolytic cell and the measurement is made by weighing the element deposited or released at the cathode in a specified time. Silver voltameter This is the most accurate type. It consists of two silver plates in a solution of silver nitrate. When current is flowing, silver dissolves at the anode and is deposited at the cathode. The cathode is initially massed, current is passed for a measured time and the cathode is massed again. Copper coulometer This is similar to the silver voltameter but the anode and cathode are copper and the solution is copper sulfate, acidified with sulfuric acid. It is cheaper tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absorption (optics)
In physics, absorption of electromagnetic radiation is how matter (typically electrons bound in atoms) takes up a photon's energy — and so transforms electromagnetic energy into internal energy of the absorber (for example, thermal energy). A notable effect is attenuation, or the gradual reduction of the intensity of light waves as they propagate through a medium. Although the absorption of waves does not usually depend on their intensity (linear absorption), in certain conditions (optics) the medium's transparency changes by a factor that varies as a function of wave intensity, and saturable absorption (or nonlinear absorption) occurs. Quantifying absorption Many approaches can potentially quantify radiation absorption, with key examples following. * The absorption coefficient along with some closely related derived quantities * The attenuation coefficient (NB used infrequently with meaning synonymous with "absorption coefficient") * The Molar attenuation coefficient (al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Atmosphere
The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing for liquid water to exist on the Earth's surface, absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation). By mole fraction (i.e., by number of molecules), dry air contains 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere. Air composition, temperature, and atmospheric pressure vary with altitude. Within the atmosphere, air suitable for use in photosynthesis by terrestrial plants and breathing of terrestrial animals is found only in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
