|
Association Of Lunar And Planetary Observers
The Association of Lunar and Planetary Observers (ALPO or A.L.P.O.) is an international scientific and educational organization established in March 1947 in the United States by Walter H. Haas, and later incorporated in 1990. ALPO is an organization for advancing and conducting astronomical work by both professional and amateur astronomers who share an interest in Solar System observations. It is currently headquartered in Springfield, Illinois. ALPO studies Solar System objects such as the Sun, the Earth's Moon, planets, asteroids, meteors, and comets. ALPO stimulates, coordinates, and generally promotes the study of these bodies using methods and instruments available within the communities of both amateur and professional astronomers. The organization holds a conference each summer, usually in conjunction with other astronomical groups. Sections ALPO had no initial formal structure but later found it necessary to specialize as its membership chose to narrow their studies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-profit Organization
A nonprofit organization (NPO), also known as a nonbusiness entity, nonprofit institution, not-for-profit organization, or simply a nonprofit, is a non-governmental (private) legal entity organized and operated for a collective, public, or social benefit, as opposed to an entity that operates as a business aiming to generate a Profit (accounting), profit for its owners. A nonprofit organization is subject to the non-distribution constraint: any revenues that exceed expenses must be committed to the organization's purpose, not taken by private parties. Depending on the local laws, charities are regularly organized as non-profits. A host of organizations may be non-profit, including some political organizations, schools, hospitals, business associations, churches, foundations, social clubs, and consumer cooperatives. Nonprofit entities may seek approval from governments to be Tax exemption, tax-exempt, and some may also qualify to receive tax-deductible contributions, but an enti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discussion Boards
Conversation is interactive communication between two or more people. The development of conversational skills and etiquette is an important part of socialization. The development of conversational skills in a new language is a frequent focus of language teaching and learning. Conversation analysis is a branch of sociology which studies the structure and organization of human interaction, with a more specific focus on conversational interaction. Definition and characterization No generally accepted definition of conversation exists, beyond the fact that a conversation involves at least two people talking together. Consequently, the term is often defined by what it is not. A ritualized exchange such as a mutual greeting is not a conversation, and an interaction that includes a marked status differential (such as a boss giving orders) is also not a conversation. An interaction with a tightly focused topic or purpose is also generally not considered a conversation. Summarizi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Publication
To publish is to make content available to the general public.Berne Convention, article 3(3) URL last accessed 2025-05-23.Universal Copyright Convention, Geneva text (1952), article VI . URL last accessed 2010-05-10. While specific use of the term may vary among countries, it is usually applied to , images, or other [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Administration Of Business
Administration may refer to: Management of organizations * Management, the act of directing people towards accomplishing a goal: the process of dealing with or controlling things or people. ** Administrative assistant, traditionally known as a secretary, or also known as an administrative officer, administrative support specialist, or management assistant: a person whose work consists of supporting management ** Administration (government), management in or of government, the management of public affairs; government. *** Administrative division, a term for an administrative region within a country that is created for the purpose of managing of land and the affairs of people. ** Academic administration, a branch of an academic institution responsible for the maintenance and supervision of the institution ** Arts administration, a field that concerns business operations around an art organization ** Business administration, the performance or management of business operations *** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History
History is the systematic study of the past, focusing primarily on the Human history, human past. As an academic discipline, it analyses and interprets evidence to construct narratives about what happened and explain why it happened. Some theorists categorize history as a social science, while others see it as part of the humanities or consider it a hybrid discipline. Similar debates surround the purpose of history—for example, whether its main aim is theoretical, to uncover the truth, or practical, to learn lessons from the past. In a more general sense, the term ''history'' refers not to an academic field but to the past itself, times in the past, or to individual texts about the past. Historical research relies on Primary source, primary and secondary sources to reconstruct past events and validate interpretations. Source criticism is used to evaluate these sources, assessing their authenticity, content, and reliability. Historians strive to integrate the perspectives o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Transit
In astronomy, a transit (or astronomical transit) is the passage of a astronomical object, celestial body directly between a larger body and the observer. As viewed from a particular vantage point, the transiting body appears to move across the face of the larger body, eclipse, covering a small portion of it. The word "transit" refers to cases where the nearer object apparent size, appears smaller than the more distant object. Cases where the nearer object appears larger and completely hides the more distant object are known as occultation, ''occultations''. However, the probability of seeing a transiting planet is low because it is dependent on the alignment of the three objects in a nearly perfectly straight line. Many parameters of a planet and its parent star can be determined based on the transit. In the Solar System One type of transit involves the motion of a planet between a Earth, terrestrial observer and the Sun. This can happen only with inferior and superior pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eclipse
An eclipse is an astronomical event which 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''. An eclipse is the result of either an '' occultation'' (completely hidden) or a ''transit'' (partially hidden). A "deep eclipse" (or "deep occultation") is when a small astronomical object is behind a bigger one. "What is a deep eclipse? The smaller star is behind the bigger star" 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined and slightly less than one-thousandth the mass of the Sun. Its diameter is 11 times that of Earth and a tenth that of the Sun. Jupiter orbits the Sun at a distance of , with an orbital period of . It is the List of brightest natural objects in the sky, third-brightest natural object in the Earth's night sky, after the Moon and Venus, and has been observed since prehistoric times. Its name derives from that of Jupiter (god), Jupiter, the chief deity of ancient Roman religion. Jupiter was the first of the Sun's planets to form, and its inward migration during the primordial phase of the Solar System affected much of the formation history of the other planets. Jupiter's atmosphere consists of 76% hydrogen and 24% helium by mass, with a denser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minor Planet
According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''minor planet'', but that year's meeting IAU definition of planet, reclassified minor planets and comets into dwarf planets and Small Solar System body, small Solar System bodies (SSSBs).Press release, IAU 2006 General Assembly: Result of the IAU Resolution votes International Astronomical Union, August 24, 2006. Accessed May 5, 2008. In contrast to the eight official planets of the Solar System, all minor planets fail to clearing the neighborhood, clear their orbital neighborhood. Minor planets include asteroids (near- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorite
A meteorite is a rock (geology), rock that originated in outer space and has fallen to the surface of a planet or Natural satellite, moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a Meteoroid#Fireball, fireball, also known as a shooting star; astronomers call the brightest examples "Bolide#Astronomy, bolides". Once it settles on the larger body's surface, the meteor becomes a meteorite. Meteorites vary greatly in size. For geologists, a bolide is a meteorite large enough to create an impact crater. Meteorites that are recovered after being observed as they transit the atmosphere and impact event, impact Earth are called meteorite falls. All others are known as meteorite finds. Meteorites have traditionally been divided into three broad categories: stony meteorites that are rocks, mainly composed of sil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venus
Venus is the second planet from the Sun. It is often called Earth's "twin" or "sister" planet for having almost the same size and mass, and the closest orbit to Earth's. While both are rocky planets, Venus has an atmosphere much thicker and denser than Earth and any other rocky body in the Solar System. Its atmosphere is composed of mostly carbon dioxide (), with a global sulfuric acid cloud cover and no liquid water. At the mean surface level the atmosphere reaches a temperature of and a pressure 92 times greater than Earth's at sea level, turning the lowest layer of the atmosphere into a supercritical fluid. Venus is the third brightest object in Earth's sky, after the Moon and the Sun, and, like Mercury, appears always relatively close to the Sun, either as a "morning star" or an "evening star", resulting from orbiting closer ( inferior) to the Sun than Earth. The orbits of Venus and Earth make the two planets approach each other in synodic periods of 1.6 years ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
