|
U (trans-Neptunian Object)
Following the discovery of the planet Neptune in 1846, there was considerable speculation that another planet might exist beyond its orbit. The search began in the mid-19th century and continued at the start of the 20th with Percival Lowell's quest for Planet X. Lowell proposed the Planet X hypothesis to explain apparent discrepancies in the orbits of the giant planets, particularly Uranus and Neptune, speculating that the gravity of a large unseen ninth planet could have perturbed Uranus enough to account for the irregularities. Clyde Tombaugh's discovery of Pluto in 1930 appeared to validate Lowell's hypothesis, and Pluto was officially named the ninth planet. In 1978, Pluto was conclusively determined to be too small for its gravity to affect the giant planets, resulting in a brief search for a tenth planet. The search was largely abandoned in the early 1990s, when a study of measurements made by the ''Voyager 2'' spacecraft found that the irregularities observed in ... [...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] |
Wide-field Infrared Survey Explorer
Wide-field Infrared Survey Explorer (WISE, List of observatory codes, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy Space observatory, space telescope in the Explorers Program launched in December 2009.. . WISE List of minor planet discoverers#WISE, discovered thousands of minor planets and numerous star clusters. Its observations also supported the discovery of the first Y dwarf, Y-type brown dwarf and Earth trojan, Earth trojan asteroid. ... . WISE performed an all-sky astronomical survey with images in 3.4, 4.6, 12 and 22 μm wavelength range bands, over ten months using a diameter infrared telescope in Geocentric orbit, Earth orbit. After its solid hydrogen coolant depleted, it was placed in Hibernation (spaceflight), hibernation mode in February 2011. In 2013, NASA reactivated the WISE telescope to search for near-Earth objects (NEO), such as comets and asteroids, that could collide with Earth. The reactivation mission was called Near-Eart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexis Bouvard
Alexis Bouvard (, 27 June 1767 – 7 June 1843) was a French astronomer. He is particularly noted for his careful observations of the irregularities in the motion of Uranus and his hypothesis of the existence of an eighth planet in the Solar System. Life Born in Contamines, Duchy of Savoy, Bouvard's achievements included the discovery of eight comets and the compilation of astronomical tables of Jupiter, Saturn and Uranus. While the former two tables were eminently successful, the latter showed substantial discrepancies with subsequent observations. This led Bouvard to hypothesise the existence of an eighth planet responsible for the irregularities in Uranus' orbit. non.(2001) The position of Neptune was subsequently calculated from Bouvard's observations by Urbain Le Verrier after his death. Bouvard was eventually director of the Paris Observatory after starting there as a student astronomer in 1793 and working under Pierre-Simon Laplace. He died in Paris. Honours *Member '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas John Hussey
Thomas John Hussey (4 April 1797 – c. 1866) was an English clergyman and astronomer. Background and education T. J. Hussey was born in Lamberhurst, Kent, the only son of Rev. John Hussey and Catherine Jennings. The Husseys were an old, armigerous, Anglo-Norman family and substantial local landowners, the Rev. Hussey being the younger brother of Edward Hussey of Scotney Castle. Thomas Hussey's father died in Allahabad in 1799, leaving Catherine to look after her son. She sent him to Eton, but subsequently became financially embroiled with an Irish barrister, J. P. Maccabe, who claimed to be her nephew. According to a deed of gift written by (or as if by) Catherine, young Thomas, whilst still at Eton, "rendered me miserable...took a considerable sum of money from me, and went away, I knew not whither. He enlisted: my hopes were blasted of ever seeing him either respectable in life, or a man of education...I knew my unfortunate boy well and feared the worst. My son's uncle...E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Planet
A giant planet, sometimes referred to as a jovian planet (''Jove'' being another name for the Roman god Jupiter (mythology), Jupiter), is a diverse type of planet much larger than Earth. Giant planets are usually primarily composed of low-boiling point materials (volatile (astrogeology), volatiles), rather than rock (geology), rock or other solid matter, but massive solid planets can also exist. There are four such planets in the Solar System: Jupiter, Saturn, Uranus, and Neptune. Many exoplanet, extrasolar giant planets have been identified. Giant planets are sometimes known as gas giants, but many astronomers now apply the term only to Jupiter and Saturn, classifying Uranus and Neptune, which have different compositions, as ice giants. Both names are potentially misleading; the Solar System's giant planets all consist primarily of fluids above their critical point (thermodynamics), critical points, where distinct gas and liquid phases do not exist. Jupiter and Saturn are princip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heinrich Louis D'Arrest
Heinrich Louis d'Arrest (13 August 1822 – 14 June 1875; ) was a German astronomer, born in Berlin. His name is sometimes given as Heinrich Ludwig d'Arrest. Biography While still a student at the University of Berlin, d'Arrest was party to Johann Gottfried Galle's search for Neptune. On 23 September 1846, he suggested that a recently drawn chart of the sky, in the region of Urbain Le Verrier's predicted location, could be compared with the current sky to seek the displacement characteristic of a planet, as opposed to a stationary star. Neptune was discovered that very night. D'Arrest's later work at the Leipzig Observatory led him, in 1851, to the discovery of the comet named for him (formally designated 6P/d'Arrest). He also studied asteroids, discovering 76 Freia, nebulae, and galaxies, discovering NGC 1 in 1861 and NGC 26 and NGC 358 in 1865. In 1864 D'Arrest made an unsuccessful search for Martian satellites, and posited an upper limit of 70 minutes of arc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Gottfried Galle
Johann Gottfried Galle (9 June 1812 – 10 July 1910) was a German astronomer from Radis, Germany, at the Berlin Observatory who, on 23 September 1846, with the assistance of student Heinrich Louis d'Arrest, was the first person to view the planet Neptune and know what he was looking at. Urbain Le Verrier had predicted the existence and position of Neptune, and sent the coordinates to Galle, asking him to verify. Galle found Neptune in the same night he received Le Verrier's letter, within 1° of the predicted position. The discovery of Neptune is widely regarded as a dramatic validation of celestial mechanics, and is one of the most remarkable moments of 19th-century science. Early life Galle was born in the Papsthaus (a house in the Pabst wood) 2 km west of Radis in the vicinity of the town of Gräfenhainichen, as the first son of Marie Henriette ''née Pannier'' (1790–1839) and Johann Gottfried Galle (1790–1853), an operator of a tar oven. He attended the Gymn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classical Mechanics
Classical mechanics is a Theoretical physics, physical theory describing the motion of objects such as projectiles, parts of Machine (mechanical), machinery, spacecraft, planets, stars, and galaxies. The development of classical mechanics involved Scientific Revolution, substantial change in the methods and philosophy of physics. The qualifier ''classical'' distinguishes this type of mechanics from physics developed after the History of physics#20th century: birth of modern physics, revolutions in physics of the early 20th century, all of which revealed limitations in classical mechanics. The earliest formulation of classical mechanics is often referred to as Newtonian mechanics. It consists of the physical concepts based on the 17th century foundational works of Sir Isaac Newton, and the mathematical methods invented by Newton, Gottfried Wilhelm Leibniz, Leonhard Euler and others to describe the motion of Physical body, bodies under the influence of forces. Later, methods bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urbain Le Verrier
Urbain Jean Joseph Le Verrier (; 11 March 1811 – 23 September 1877) was a French astronomer and mathematician who specialized in celestial mechanics and is best known for predicting the existence and position of Neptune using only mathematics. The calculations were made to explain discrepancies with Uranus's orbit and the laws of Kepler and Newton. Le Verrier sent the coordinates to Johann Gottfried Galle in Berlin, asking him to verify. Galle found Neptune the same night he received Le Verrier's letter, within 1° of the predicted position. The discovery of Neptune is widely regarded as a dramatic validation of celestial mechanics, and is one of the most remarkable moments of 19th-century science. Life Early years Urbain Le Verrier was born at Saint-Lô, Manche, France, to a modest bourgeois family, his parents being Louis-Baptiste Le Verrier and Marie-Jeanne-Josephine-Pauline de Baudre. He studied at the École Polytechnique – briefly chemistry, under Gay-Lussac, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
