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1997 In Science
The year 1997 in science and technology involved many significant events, listed below. Astronomy and space exploration * January 17 – Explosion of a Delta II rocket carrying a military GPS payload shortly after liftoff from Cape Canaveral. * February 13 – Tune-up and repair work on the Hubble Space Telescope is started by astronauts from the Space Shuttle ''Discovery''. * February 27 – GRB 970228, a highly luminous flash of gamma rays, strikes the Earth for 80 seconds, providing early evidence that gamma-ray bursts occur well beyond the Milky Way. * March 8 – Complete solar eclipse. * March 24 – Partial lunar eclipse. * July 4 – ''Mars Pathfinder'' lands on the surface of Mars. * August 25 – Launch of Explorer 71 of the Explorer program of spacecraft. * September 2 – Partial solar eclipse. * September – Total lunar eclipse. * October 15 – Launch of 10-year ''Cassini–Huygens'' spacecraft to Saturn. * October 30 – First successful test flight of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
September 1997 Lunar Eclipse
A total lunar eclipse occurred at the Moon’s Lunar node, descending node of orbit on Tuesday, September 16, 1997, with an umbral Magnitude of eclipse, magnitude of 1.1909. A lunar eclipse occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. A total lunar eclipse occurs when the Moon's near side entirely passes into the Earth's umbral shadow. Unlike a solar eclipse, which can only be viewed from a relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of Earth. A total lunar eclipse can last up to nearly two hours, while a total solar eclipse lasts only a few minutes at any given place, because the Moon's Umbra, penumbra and antumbra, shadow is smaller. Occurring only about 2.5 hours after Apsis, perigee (on September 16, 1997, at 16:20 UTC), the Moon's apparent diameter was larger. This lunar eclipse was the last of an Tetrad (astronomy), almost tetrad, with the others being on April 1996 lunar eclipse, Ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Cloning
Human cloning is the creation of a genetically Cloning, identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human Cell (biology), cells and Tissue (biology), tissue. It does not refer to the natural conception and delivery of monozygotic, identical multiple birth, twins. The possibilities of human cloning ethics of cloning, have raised controversies. These ethical concerns have prompted several nations to pass laws regarding human cloning. Two commonly discussed types of human cloning are ''therapeutic cloning'' and ''reproductive cloning''. Therapeutic cloning would involve cloning cells from a human for use in medicine and transplants. It is an active area of research, and is in medical practice over the world. Two common methods of therapeutic cloning that are being researched are somatic-cell nuclear transfer and (more recently) Induced pluripotent stem cell, pluripotent stem cell induction. Reproductive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bill Clinton
William Jefferson Clinton (né Blythe III; born August 19, 1946) is an American politician and lawyer who was the 42nd president of the United States from 1993 to 2001. A member of the Democratic Party (United States), Democratic Party, he previously served as the attorney general of Arkansas from 1977 to 1979 and as the governor of Arkansas from 1979 to 1981, and again from 1983 to 1992. Clinton, whose policies reflected a centrist "Third Way" political philosophy, became known as a New Democrats (United States), New Democrat. Born and raised in Arkansas, Clinton graduated from Georgetown University in 1968, and later from Yale Law School, where he met his future wife, Hillary Clinton, Hillary Rodham. After graduating from law school, Clinton returned to Arkansas and won election as state attorney general, followed by Governorships of Bill Clinton, two non-consecutive tenures as Arkansas governor. As governor, he overhauled the state's education system and served as Chai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1996 In Science
1996 was designated as: * International Year for the Eradication of Poverty Events January * January 8 – A Zairean cargo plane crashes into a crowded market in the center of the capital city of the Democratic Republic of the Congo, Kinshasa, killing around 300 people. * January 9– 20 – Serious fighting breaks out between Russian soldiers and rebel fighters in Chechnya. * January 11 – Ryutaro Hashimoto, leader of the Liberal Democratic Party, becomes Prime Minister of Japan. * January 13 – Italy's Prime Minister, Lamberto Dini, resigns after the failure of all-party talks to confirm him. New talks are initiated by President Oscar Luigi Scalfaro to form a new government. * January 14 – Jorge Sampaio is elected President of Portugal. * January 16 – President of Sierra Leone Valentine Strasser is deposed by the chief of defence, Julius Maada Bio. Bio promises to restore power following elections scheduled for February. * January 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloning
Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction; this reproduction of an organism by itself without a mate is known as parthenogenesis. In the field of biotechnology, cloning is the process of creating cloned organisms of Cell (biology), cells and of DNA fragments. The artificial cloning of organisms, sometimes known as reproductive cloning, is often accomplished via somatic-cell nuclear transfer (SCNT), a cloning method in which a viable embryo is created from a somatic cell and an egg cell. In 1996, Dolly (sheep), Dolly the sheep achieved notoriety for being the first mammal cloned from a somatic cell. Another example of artificial cloning is molecular cloning, a technique in molecular biology in which a single living cell is used to clone a large population of cells that contain identical DNA molecules. In bioethics, there are a vari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolly The Sheep
Dolly (5 July 1996 – 14 February 2003) was a female Finn-Dorset sheep and the first mammal that was cloned from an adult somatic cell. She was cloned by associates of the Roslin Institute in Scotland, using the process of nuclear transfer from a cell taken from a mammary gland. Her cloning proved that a cloned organism could be produced from a mature cell from a specific body part. Contrary to popular belief, she was not the first animal to be cloned. The employment of adult somatic cells in lieu of embryonic stem cells for cloning emerged from the foundational work of John Gurdon, who cloned African clawed frogs in 1958 with this approach. The successful cloning of Dolly led to widespread advancements within stem cell research, including the discovery of induced pluripotent stem cells. Dolly lived at the Roslin Institute throughout her life and produced several lambs. She was euthanized at the age of six years due to a progressive lung disease. No cause which link ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sheep
Sheep (: sheep) or domestic sheep (''Ovis aries'') are a domesticated, ruminant mammal typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to domesticated sheep. Like all ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Numbering a little over one billion, domestic sheep are also the most numerous species of sheep. An adult female is referred to as a ''ewe'' ( ), an intact male as a ''ram'', occasionally a ''tup'', a castrated male as a ''wether'', and a young sheep as a ''lamb''. Sheep are most likely descended from the wild mouflon of Europe and Asia, with Iran being a geographic envelope of the domestication center. One of the earliest animals to be domesticated for agricultural purposes, sheep are raised for fleeces, meat ( lamb, hogget or mutton), and milk. A sheep's wool is the most widely used animal fiber, and is usually harvested by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roslin, Scotland
Roslin (formerly spelt Rosslyn or Roslyn) is a village in Midlothian, Scotland, 11 kilometres (7 mi) to the south of the capital city Edinburgh. It stands on high ground, near the northwest bank of the river River Esk, Lothian, North Esk. The name The name Roslin (recorded in 1138 as ''Roskelyn'') appears to derive from Scottish Gaelic. The second element is clearly ''linne'' usually meaning a pond or a lake, but here probably means a waterfall and refers to the nearby Linn of Roslin. The first element is more obscure, but may derive from ''riasg'' meaning a peat moor. The theory that it is a corruption of ''Rose line'', a supposed medieval meridian passing through Paris and Rosslyn Chapel, is fanciful. Roslin is believed to be the source of the name for the Roslyn, New York, Village of Roslyn, on Long Island, in the United States, U.S. New York (state), State of New York; its location reminded officials of the hills in Roslin. Roslindale, Massachusetts is also named afte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fifth-generation Jet Fighter
A fifth-generation fighter is a Jet fighter generations, jet fighter aircraft classification which includes major technologies developed during the first part of the 21st century. these are the most advanced fighters in operation. The characteristics of a fifth-generation fighter are not universally agreed upon, and not every fifth-generation type necessarily has them all; however, they typically include stealth technology, stealth, low-probability-of-intercept radar (LPIR), agile airframes with supercruise performance, advanced avionics features, and highly integrated computer systems capable of network-centric warfare, networking with other elements within the battlespace for situational awareness and C3 (Command and control, command, control and communications) capabilities. the combat-ready fifth-generation fighters are the Lockheed Martin F-22 Raptor, which entered service with the United States Air Force (USAF) in December 2005; the Lockheed Martin F-35 Lightning II, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lockheed Martin F-22 Raptor
The Lockheed Martin/Boeing F-22 Raptor is an American Twinjet, twin-engine, Jet engine, jet-powered, Night fighter, all-weather, supersonic Stealth aircraft, stealth fighter aircraft. As a product of the United States Air Force's Advanced Tactical Fighter (ATF) program, the aircraft was designed as an air superiority fighter, but also incorporates attack aircraft, ground attack, electronic-warfare aircraft, electronic warfare, and signals intelligence capabilities. The prime contractor, Lockheed Martin Aeronautics, Lockheed Martin, built most of the F-22 airframe and weapons systems and conducted final assembly, while program partner Boeing Defense, Space & Security, Boeing provided the wings, aft fuselage, avionics integration, and training systems. First flown in 1997, the F-22 descended from the Lockheed YF-22 and was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Although the U.S. Air Force (USAF) had originally plan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expendable Launch System
An expendable launch system (or expendable launch vehicle/ELV) is a launch vehicle that can be launched only once, after which its components are destroyed during reentry or impact with Earth, or discarded in space. ELVs typically consist of several rocket stages that are discarded sequentially as their fuel is exhausted and the vehicle gains altitude and speed. As of 2024, fewer and fewer satellites and human spacecraft are launched on ELVs in favor of reusable launch vehicles. However, there are many instances where a ELV may still have a compelling use case over a reusable vehicle. ELVs are simpler in design than reusable launch systems and therefore may have a lower production cost. Furthermore, an ELV can use its entire fuel supply to accelerate its payload, offering greater payloads. ELVs are a proven technology in widespread use for many decades. Current operators Arianespace China ISRO During the 1960s and 1970s, India initiated its own launch vehicle program ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
