Pierre Encrenaz
Pierre Encrenaz (born 14 September 1945) is a French astronomer who is a professor at the Université Pierre-et-Marie-Curie (Paris VI). He was also head of the École doctorale d'Astronomie et d'Astrophysique d'Île-de-France. He was elected a member of the French Academy of Sciences in December 2000, in the "Universe Sciences" section. Biography After secondary studies at the Lycée Berthollet in Annecy, he entered preparatory classes at the Lycée du Parc in Lyon, then at the École normale supérieure in Paris (student, agrégé préparateur, sous-directeur) (1965-1979). * Graduate thesis: calibration of the Bell Laboratories 1970 antenna (Director Arno Penzias, Nobel Prize 1978) * State thesis: Measurement of pulsar distance by absorption 21 cm 1972 (Director James Lequeux) He spent several stays at Princeton and Bell Laboratories (1968-1973). He became an astronomer at Paris Observatory (1979-1991) and at the École normale supérieure (1973-1992). Pierre Encre ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Annecy
Annecy ( , ; frp, Èneci or ) is the Prefectures in France, prefecture and List of communes in France with over 20,000 inhabitants, largest city of the Haute-Savoie Departments of France, department in the Auvergne-Rhône-Alpes Regions of France, region of Southeastern France. It lies on the northern tip of Lake Annecy, south of Geneva, Switzerland. Nicknamed the "Pearl of French Alps" in Raoul Blanchard's monograph describing its location between lake and mountains, the city controls the northern entrance to the lake gorge. Due to a lack of available building land between the lake and the protected Semnoz mountain, its population has remained stagnant, around 50,000 inhabitants, since 1950. However, the 2017 merger with several ex-communes extended the city population to 128,199 inhabitants and 177,622 for its urban unit, urban area, placing Annecy seventh in the Auvergne-Rhône-Alpes region. Switching from the County of Geneva, counts of Geneva's dwelling in the 13th centur ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Niobium
Niobium is a chemical element with chemical symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and ductile transition metal. Pure niobium has a Mohs hardness rating similar to pure titanium, and it has similar ductility to iron. Niobium oxidizes in Earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. Niobium is often found in the minerals pyrochlore and columbite, hence the former name "columbium". Its name comes from Greek mythology: Niobe, daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, which makes them difficult to distinguish. English chemist Charles Hatchett reported a new element similar to tantalum in 1801 and named it columbium. In 1809, English chemist William Hyde Wollaston wrongly concluded that tantalum and columbium were identical. German chemist Heinrich ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1945 Births
1945 marked the end of World War II and the fall of Nazi Germany and the Empire of Japan. It is also the only year in which Nuclear weapon, nuclear weapons Atomic bombings of Hiroshima and Nagasaki, have been used in combat. Events Below, the events of World War II have the "WWII" prefix. January * January 1 – WWII: ** Nazi Germany, Germany begins Operation Bodenplatte, an attempt by the ''Luftwaffe'' to cripple Allies of World War II, Allied air forces in the Low Countries. ** Chenogne massacre: German prisoners are allegedly killed by American forces near the village of Chenogne, Belgium. * January 6 – WWII: A German offensive recaptures Esztergom, Kingdom of Hungary (1920–1946), Hungary from the Russians. * January 12 – WWII: The Soviet Union begins the Vistula–Oder Offensive in Eastern Europe, against the German Army (Wehrmacht), German Army. * January 13 – WWII: The Soviet Union begins the East Prussian Offensive, to eliminate German forces in East Pruss ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Three Physicists Prize
The Three Physicists Prize (french: Prix des trois physiciens) is a physics prize awarded by the École Normale Supérieure (ENS) in Paris and the Eugène Bloch Foundation. It is named in honour of the physicists Henri Abraham, Eugene Bloch and Georges Bruhat, who were successive directors of the physics laboratory at the ENS and all of whom were murdered in Nazi concentration camps between 1943 and 1945. The prize was established by Bloch's widow. Winners * 1951 Jean Cabannes * 1952 Maurice Bayen * 1953 Gustave Ribaud * 1954 Maurice Ponte * 1955 ''not awarded'' * 1956 Nevill Francis Mott * 1957 H. B. G. Casimir * 1958 J. Robert Oppenheimer * 1959 André Danjon * 1960 Gaston Dupouy * 1961 Max Morand * 1962 Jean Weigle * 1963 Louis Néel * 1964 André Lallemand * 1965 Alfred Kastler * 1966 Francis Perrin * 1967 Pierre Auger * 1968 Jean-François Denisse * 1969 Jean-Claude Pecker * 1970 Albert Kirrmann * 1971 Jean Coulomb * 1972 André Guinier * 1973 Pierre Grivet * 1974 Jean ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Rosetta (spacecraft)
''Rosetta'' was a space probe built by the European Space Agency launched on 2 March 2004. Along with ''Philae (spacecraft), Philae'', its lander module, ''Rosetta'' performed a detailed study of comet 67P/Churyumov–Gerasimenko (67P). During its journey to the comet, the spacecraft performed planetary flyby, flybys of Earth, Mars, and the asteroids 21 Lutetia and 2867 Šteins. It was launched as the third cornerstone mission of the ESA's Horizon 2000 programme, after ''Solar and Heliospheric Observatory, SOHO'Cluster II (spacecraft), Cluster'' and ''XMM-Newton''. On 6 August 2014, the spacecraft reached the comet and performed a series of manoeuvers to eventually orbit the comet at distances of . On 12 November, its lander module ''Philae'' performed the first successful landing on a comet, though its battery power ran out two days later. Communications with ''Philae'' were briefly restored in June and July 2015, but due to diminishing solar power, ''Rosetta'' communications ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Cassini–Huygens
''Cassini–Huygens'' ( ), commonly called ''Cassini'', was a space-research mission by NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a space probe to study the planet Saturn and its system, including its rings and natural satellites. The Flagship-class robotic spacecraft comprised both NASA's ''Cassini'' space probe and ESA's ''Huygens'' lander, which landed on Saturn's largest moon, Titan. ''Cassini'' was the fourth space probe to visit Saturn and the first to enter its orbit, where it stayed from 2004 to 2017. The two craft took their names from the astronomers Giovanni Cassini and Christiaan Huygens. Launched aboard a Titan IVB/Centaur on October 15, 1997, ''Cassini'' was active in space for nearly 20 years, with 13 years spent orbiting Saturn and studying the planet and its system after entering orbit on July 1, 2004. The voyage to Saturn included flybys of Venus (April 1998 and July 1999), Earth (August 1999), the asteroid 2685 Ma ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Remote Sensing
Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring information about Earth and other planets. Remote sensing is used in numerous fields, including geography, land surveying and most Earth science disciplines (e.g. hydrology, ecology, meteorology, oceanography, glaciology, geology); it also has military, intelligence, commercial, economic, planning, and humanitarian applications, among others. In current usage, the term ''remote sensing'' generally refers to the use of satellite- or aircraft-based sensor technologies to detect and classify objects on Earth. It includes the surface and the atmosphere and oceans, based on propagated signals (e.g. electromagnetic radiation). It may be split into "active" remote sensing (when a signal is emitted by a satellite or aircraft to the object and its reflection dete ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
YouTube
YouTube is a global online video sharing and social media platform headquartered in San Bruno, California. It was launched on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim. It is owned by Google, and is the second most visited website, after Google Search. YouTube has more than 2.5 billion monthly users who collectively watch more than one billion hours of videos each day. , videos were being uploaded at a rate of more than 500 hours of content per minute. In October 2006, YouTube was bought by Google for $1.65 billion. Google's ownership of YouTube expanded the site's business model, expanding from generating revenue from advertisements alone, to offering paid content such as movies and exclusive content produced by YouTube. It also offers YouTube Premium, a paid subscription option for watching content without ads. YouTube also approved creators to participate in Google's AdSense program, which seeks to generate more revenue for both parties. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Lakes Of Titan
Lakes of ethane and methane on Titan, Saturn's largest moon, have been detected by the ''Cassini–Huygens'' space probe, and had been suspected long before. The large ones are known as maria (seas) and the small ones as lacūs (lakes). History The possibility that there were seas on Titan was first suggested based on data from the Voyager 1 and 2 space probes, launched in August and September 1977. The data showed Titan to have a thick atmosphere of approximately the correct temperature and composition to support them. Direct evidence was not obtained until 1995 when data from the Hubble Space Telescope and other observations had already suggested the existence of liquid methane on Titan, either in disconnected pockets or on the scale of satellite-wide oceans, similar to water on Earth. The ''Cassini'' mission affirmed the former hypothesis, although not immediately. When the probe arrived in the Saturnian system in 2004, it was hoped that hydrocarbon lakes or oceans might ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Pulsar
A pulsar (from ''pulsating radio source'') is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation out of its magnetic poles. This radiation can be observed only when a beam of emission is pointing toward Earth (similar to the way a lighthouse can be seen only when the light is pointed in the direction of an observer), and is responsible for the pulsed appearance of emission. Neutron stars are very dense and have short, regular rotational periods. This produces a very precise interval between pulses that ranges from milliseconds to seconds for an individual pulsar. Pulsars are one of the candidates for the source of ultra-high-energy cosmic rays. (See also centrifugal mechanism of acceleration.) The periods of pulsars make them very useful tools for astronomers. Observations of a pulsar in a binary neutron star system were used to indirectly confirm the existence of gravitational radiation. The first extrasolar planets were discovere ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Rosetta Probe
''Rosetta'' was a space probe built by the European Space Agency launched on 2 March 2004. Along with ''Philae (spacecraft), Philae'', its lander module, ''Rosetta'' performed a detailed study of comet 67P/Churyumov–Gerasimenko (67P). During its journey to the comet, the spacecraft performed planetary flyby, flybys of Earth, Mars, and the asteroids 21 Lutetia and 2867 Šteins. It was launched as the third cornerstone mission of the ESA's Horizon 2000 programme, after ''Solar and Heliospheric Observatory, SOHO'Cluster II (spacecraft), Cluster'' and ''XMM-Newton''. On 6 August 2014, the spacecraft reached the comet and performed a series of manoeuvers to eventually orbit the comet at distances of . On 12 November, its lander module ''Philae'' performed the first successful landing on a comet, though its battery power ran out two days later. Communications with ''Philae'' were briefly restored in June and July 2015, but due to diminishing solar power, ''Rosetta'' communications ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Comet
A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or Coma (cometary), coma, and sometimes also a Comet tail, tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently bright, a comet may be seen from Earth without the aid of a telescope and may Subtended angle, subtend an arc of 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religions. Comets usually have highly Orbital eccentricity, eccentric elliptical orbits, and they have a wide range of orbit ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |