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Timeline Of United States Discoveries
Timeline of United States discoveries encompasses the breakthroughs of human thought and knowledge of new scientific findings, phenomena, places, things, and what was previously unknown to exist. From a historical standpoint, the timeline below of United States discoveries dates from the 18th century to the current 21st century, which have been achieved by discoverers who are either native-born or naturalized citizens of the United States. With an emphasis of discoveries in the fields of astronomy, physics, chemistry, medicine, biology, geology, paleontology, and archaeology, United States citizens acclaimed in their professions have contributed much. For example, the "Bone Wars," beginning in 1877 and ending in 1892, was an intense period of rivalry between two American paleontologists, Edward Drinker Cope and Othniel Charles Marsh, who initiated several expeditions throughout North America in the pursuit of discovering, identifying, and finding new species of dinosaur fossil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Othniel Charles Marsh & Edward Drinker Cope Bw
Othniel (; , ''ʿOṯnīʾēl ben Qǝnaz'') was the first of the biblical judges. The etymology of his name is uncertain, but may mean "God/He is my strength" or "God has helped me". Family The Hebrew Bible refers to Othniel as "Othniel the son of Kenaz, the brother of Caleb". The expression is inconclusive in Hebrew, and has been taken to mean either that Othniel himself was the brother of Caleb, or that Othniel's father Kenaz was the brother of Caleb. The Talmud argues that Othniel was Caleb's brother. When Caleb promises the hand of his daughter Achsah to whoever conquers the land of Debir, it is Othniel who rises to the challenge, thus becoming Caleb's son-in-law. Campaign as a Judge The historical reality of events described in the Book of Judges is the subject of ongoing dispute among scholars, who vary in their opinions about how much of the book is historical. As to the story of Othniel in particular, biblical scholar Marc Zvi Brettler states, "The Ehud and Othnie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravitationally bound Planetary system, system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, forming the Sun and a protoplanetary disc. The Sun is a typical star that maintains a hydrostatic equilibrium, balanced equilibrium by the thermonuclear fusion, fusion of hydrogen into helium at its stellar core, core, releasing this energy from its outer photosphere. As ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johnston Atoll
Johnston Atoll is an Unincorporated territories of the United States, unincorporated territory of the United States, under the jurisdiction of the United States Air Force (USAF). The island is closed to public entry, and limited access for management needs is only granted by a letter of authorization from the USAF. A special use permit is also required from the United States Fish and Wildlife Service (USFWS) to access the island by boat or enter the waters surrounding the island, which are designated as a National Wildlife Refuge and part of the Pacific Islands Heritage Marine National Monument. The Johnston Atoll National Wildlife Refuge extends from the shore out to 12 nautical miles, continuing as part of the National Wildlife Refuge System out to 200 nautical miles. The Pacific Remote Islands Marine National Monument extends from the shore out to 200 nautical miles. The isolated atoll has been under the control of the United States Armed Forces, U.S. military since 1934. Dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benjamin Franklin
Benjamin Franklin (April 17, 1790) was an American polymath: a writer, scientist, inventor, statesman, diplomat, printer, publisher and Political philosophy, political philosopher.#britannica, Encyclopædia Britannica, Wood, 2021 Among the most influential intellectuals of his time, Franklin was one of the Founding Fathers of the United States; a Committee of Five, drafter and signer of the United States Declaration of Independence, Declaration of Independence; and the first United States Postmaster General, postmaster general. Born in the Province of Massachusetts Bay, Franklin became a successful Early American publishers and printers, newspaper editor and printer in Philadelphia, the leading city in the colonies, publishing ''The Pennsylvania Gazette'' at age 23. He became wealthy publishing this and ''Poor Richard's Almanack'', which he wrote under the pseudonym "Richard Saunders". After 1767, he was associated with the ''Pennsylvania Chronicle'', a newspaper known for it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conserved Quantity
A conserved quantity is a property or value that remains constant over time in a system even when changes occur in the system. In mathematics, a conserved quantity of a dynamical system is formally defined as a function of the dependent variables, the value of which remains constant along each trajectory of the system. Not all systems have conserved quantities, and conserved quantities are not unique, since one can always produce another such quantity by applying a suitable function, such as adding a constant, to a conserved quantity. Since many laws of physics express some kind of conservation, conserved quantities commonly exist in mathematical models of physical systems. For example, any classical mechanics model will have mechanical energy as a conserved quantity as long as the forces involved are conservative. Differential equations For a first order system of differential equations :\frac = \mathbf f(\mathbf r, t) where bold indicates vector quantities, a scala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negative Charge
Electric charge (symbol ''q'', sometimes ''Q'') is a physical property of matter that causes it to experience a force when placed in an electromagnetic field. Electric charge can be ''positive'' or ''negative''. Like charges repel each other and unlike charges attract each other. An object with no net charge is referred to as electrically neutral. Early knowledge of how charged substances interact is now called classical electrodynamics, and is still accurate for problems that do not require consideration of quantum effects. In an isolated system, the total charge stays the same - the amount of positive charge minus the amount of negative charge does not change over time. Electric charge is carried by subatomic particles. In ordinary matter, negative charge is carried by electrons, and positive charge is carried by the protons in the nuclei of atoms. If there are more electrons than protons in a piece of matter, it will have a negative charge, if there are fewer it will have a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charge Conservation
In physics, charge conservation is the principle, of experimental nature, that the total electric charge in an isolated system never changes. The net quantity of electric charge, the amount of positive charge minus the amount of negative charge in the universe, is always '' conserved''. Charge conservation, considered as a physical conservation law, implies that the change in the amount of electric charge in any volume of space is exactly equal to the amount of charge flowing into the volume minus the amount of charge flowing out of the volume. In essence, charge conservation is an accounting relationship between the amount of charge in a region and the flow of charge into and out of that region, given by a continuity equation between charge density \rho(\mathbf) and current density \mathbf(\mathbf). This does not mean that individual positive and negative charges cannot be created or destroyed. Electric charge is carried by subatomic particles such as electrons and proton ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar And Planetary Laboratory
The Lunar and Planetary Laboratory (LPL) is a research center for planetary science located in Tucson, Arizona. It is also a graduate school, constituting the Department of Planetary Sciences at the University of Arizona. LPL is one of the world's largest programs dedicated exclusively to planetary science in a university setting. The Lunar and Planetary Lab collection is held at the University of Arizona Special Collections Library. Background LPL was founded in 1960 by astronomer Gerard Kuiper. Kuiper had long been a pioneer in observing the Solar System, especially the Moon, at a time when this was unfashionable among astronomers. Among his contributions are the discovery of Miranda and Nereid, the detection of carbon dioxide on Mars and of methane on Titan, and the prediction of the Kuiper Belt. Kuiper came to Tucson looking for greater independence than he had enjoyed at the University of Chicago, the chance to build a community dedicated to solar system studies, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Arizona
The University of Arizona (Arizona, U of A, UArizona, or UA) is a Public university, public Land-grant university, land-grant research university in Tucson, Arizona, United States. Founded in 1885 by the 13th Arizona Territorial Legislature, it was the first university established in the Arizona Territory. The University of Arizona is one of three universities governed by the Arizona Board of Regents (the University of Arizona, Arizona State University, and Northern Arizona University). , the university enrolled 53,187 students in 22 separate colleges/schools, including the Eller College of Management, the Wyant College of Optical Sciences, the University of Arizona College of Medicine – Phoenix, College of Medicine – Phoenix, the University of Arizona College of Medicine – Tucson, College of Medicine – Tucson, and the James E. Rogers College of Law. The university is Carnegie Classification of Institutions of Higher Education, classified among "R1: Doctoral Universities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peter Smith (physicist)
Peter H. Smith is a professor emeritus (he retired in 2013) at the Lunar and Planetary Laboratory of the University of Arizona, where he holds the inaugural Thomas R. Brown Distinguished Chair in Integrative Science. He is also the principal investigator for the $420 million robotic explorer Phoenix which landed at the north pole of the planet Mars on May 25, 2008. Peter H. Smith's papers are held at the University of Arizona Special Collections Library. Early life and education Peter H. Smith was born December 2, 1947, in New York and was raised in Tucson, Arizona. Smith's father was Hugh H. Smith, a virologist who was part of the team at the Rockefeller Foundation who developed a vaccine for yellow fever in 1930's. After his retirement from the Rockefeller Foundation, Hugh H. Smith worked at the University of Arizona and founded the Tucson Society of Tropical Medicine. Smith's mother was an opera singer. Smith went to Tucson High School and received his bachelor's degree i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
