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Galaxy morphological classification

Galaxy morphological classification is a system used by astronomers to divide galaxies into groups based on their visual appearance. There are several schemes in use by which galaxies can be classified according to their morphologies, the most famous being the Hubble sequence, devised by Edwin Hubble and expanded by Gérard de Vaucouleurs and Allan Sandage. However, galaxy classification and morphology are now done using computational methods and physical morphology; the Hubble sequence is a morphological classification scheme for galaxies invented by Edwin Hubble in 1926. It is known colloquially as the “Hubble tuning-fork” because of the shape in which it is traditionally represented. Hubble's scheme divides galaxies into three broad classes based on their visual appearance: Elliptical galaxies have smooth, featureless light distributions and appear as ellipses in images, they are denoted by the letter "E", followed by an integer n representing their degree of ellipticity on the sky. Spiral galaxies consist of a flattened disk, with stars forming a spiral structure, a central concentration of stars known as the bulge, similar in appearance to an elliptical galaxy.

They are given the symbol "S". Half of all spirals are observed to have a bar-like structure, extending from the central bulge; these barred spirals are given the symbol "SB". Lenticular galaxies consist of a bright central bulge surrounded by an extended, disk-like structure but, unlike spiral galaxies, the disks of lenticular galaxies have no visible spiral structure and are not forming stars in any significant quantity; these broad classes can be extended to enable finer distinctions of appearance and to encompass other types of galaxies, such as irregular galaxies, which have no obvious regular structure. The Hubble sequence is represented in the form of a two-pronged fork, with the ellipticals on the left and the barred and unbarred spirals forming the two parallel prongs of the fork. Lenticular galaxies are placed between the ellipticals and the spirals, at the point where the two prongs meet the “handle”. To this day, the Hubble sequence is the most used system for classifying galaxies, both in professional astronomical research and in amateur astronomy.

Nonetheless, in June 2019, citizen scientists through Galaxy Zoo reported that the usual Hubble classification concerning spiral galaxies, may not be supported, may need updating. The de Vaucouleurs system for classifying galaxies is a used extension to the Hubble sequence, first described by Gérard de Vaucouleurs in 1959. De Vaucouleurs argued that Hubble's two-dimensional classification of spiral galaxies—based on the tightness of the spiral arms and the presence or absence of a bar—did not adequately describe the full range of observed galaxy morphologies. In particular, he argued that rings and lenses are important structural components of spiral galaxies; the de Vaucouleurs system retains Hubble's basic division of galaxies into ellipticals, lenticulars and irregulars. To complement Hubble's scheme, de Vaucouleurs introduced a more elaborate classification system for spiral galaxies, based on three morphological characteristics: The different elements of the classification scheme are combined — in the order in which they are listed — to give the complete classification of a galaxy.

For example, a weakly barred spiral galaxy with loosely wound arms and a ring is denoted SABc. Visually, the de Vaucouleurs system can be represented as a three-dimensional version of Hubble's tuning fork, with stage on the x-axis, family on the y-axis, variety on the z-axis. De Vaucouleurs assigned numerical values to each class of galaxy in his scheme. Values of the numerical Hubble stage T run from −6 to +10, with negative numbers corresponding to early-type galaxies and positive numbers to late types. Thus, as a rough rule, lower values of T correspond to a larger fraction of the stellar mass contained in a spheroid/bulge relative to the disk; the approximate mapping between the spheroid-to-total stellar mass ratio and the Hubble stage is MB/MT=2/256 based on local galaxies. Elliptical galaxies are divided into three'stages': compact ellipticals, normal ellipticals and late types. Lenticulars are subdivided into early and late types. Irregular galaxies can be of type magellanic irregulars or'compact'.

The use of numerical stages allows for more quantitative studies of galaxy morphology. The Yerkes scheme was created by American astronomer William Wilson Morgan. Together with Philip Keenan, Morgan developed the MK system for the classification of stars through their spectra; the Yerkes scheme uses the spectra of stars in the galaxy. Thus, for example, the Andromeda Galaxy is classified as kS5. Morphological Catalogue of Galaxies Galaxy color–magnitude diagram Galaxy Zoo William Wilson Morgan Fritz Zwicky Galaxies and the Universe - an introduction to galaxy classification Near-Infrared Galaxy Morphology Atlas, T. H. Jarrett The Spitzer Infrared Nearby Galaxies Survey Hubble Tuning-Fork, SINGS Spitzer Space Telescope Legacy Science Project Go to GalaxyZoo.org to try your hand at classifying galaxies as part of an Oxford University open community project

Harry Benns

Harry Francis Benns is an English professional footballer who plays as a midfielder for Northern Premier League Premier Division side Hyde United. He turned professional at Port Vale in May 2018, he joined Stafford Rangers on loan for the first half of the 2018–19 season, ended the campaign on loan at Kidsgrove Athletic. Released by Port Vale at the end of the 2018–19 season, he joined Hyde United. Benns came through the youth-team at Port Vale and was given a professional contract in May 2018 after being named as Youth Player of the Year for the 2017–18 season. Manager Neil Aspin gave him his debut on the final day of the 2017–18 season, a 5–0 defeat at Cambridge United on 5 May, though he entered the game as a 75th-minute substitute for Ben Whitfield when the "Valiants" were four goals down. On 23 August 2018, Benns joined Northern Premier League Premier Division side Stafford Rangers on an initial month-long loan deal – extended until the end of the 2018–19 season. On 8 September, he scored his first goal in senior football, providing Rangers with the winner in a 2–1 victory at Grimsby Borough in the first round of qualification for the FA Cup.

He was named as Stafford Rangers Player of the Month for September. On 20 March 2019, he joined Northern Premier League Division One West club Kidsgrove Athletic on loan until the end of the season. Vale manager John Askey confirmed. Benns joined Northern Premier League Premier Division side Hyde United after arriving at Ewen Fields on the first day of the 2019–20 pre-season. Speaking in May 2018, Port Vale youth-team coach Mike Ede described Benns as a creative midfielder who "is clever, has the ability to score goals and will take shots from places where you don’t think" and who "can play off to the side or as a number 10"; as of match played 24 September 2019

Defender (1981 video game)

Defender is an arcade video game developed and released by Williams Electronics in 1981. A horizontally scrolling shoot'em up, the game is set on an unnamed planet where the player must defeat waves of invading aliens while protecting astronauts. Development was led by a pinball programmer at Williams. Defender was one of the most important titles of the golden age of video arcade games, selling over 55,000 units to become the company's best-selling game and one of the highest-grossing arcade games ever. Praise among critics focused on the game's gameplay, it is listed as one of Jarvis' best contributions to the video game industry and one of the most difficult video games. Though not the first game to scroll horizontally, it created the genre of purely horizontal scrolling shooters, it was followed by sequels and many imitations. Several ports were developed for contemporary game systems, most of them by either Atari, Inc. or its software label for non-Atari platforms, Atarisoft. Defender is a two-dimensional side-scrolling shooting game set on the surface of an unnamed planet.

The player controls a spaceship as it navigates the terrain, flying either to the right. A joystick controls the ship's elevation, five buttons control its horizontal direction and weapons; the object is to destroy alien invaders, while protecting astronauts on the landscape from abduction. Humans that are abducted return as mutants. Defeating the aliens allows the player to progress to the next level. Failing to protect the astronauts, causes the planet to explode and the level to become populated with mutants. Surviving the waves of mutants results in the restoration of the planet. Players are allotted three ships to progress through the game and are able to earn more by reaching certain scoring benchmarks. A ship is lost if a hyperspace jump goes wrong. After exhausting all ships, the game ends. Defender was Williams Electronics' first attempt at developing a new video game; the popularity of coin-operated arcade games in 1979 spurred the company to shift its focus from pinball games to arcade games.

The company chose Eugene Jarvis, who had a successful record of Williams pinball games, to head development. Larry DeMar, Sam Dicker, Paul Dussault assisted Jarvis. At the time, Williams had a small staff and the management was unfamiliar with technology used for its electronic games; as a result, the staff was afforded a large amount of creative freedom. Space was a popular setting for video games at the time, Jarvis felt the abstract setting would help obscure simple graphics that lacked realism. Jarvis spent 3–4 months developing color variations of Taito's Space Invaders and Atari's Asteroids. First inspired by Space Invaders, he created a similar game with new gameplay mechanics. After spending a few weeks on the design, the team abandoned the idea, believing it lacked enjoyment. Development shifted to emulating Atari's Asteroids, but hardware differences between Asteroids and Defender's proposed specifications were problematic. Asteroids displays vector graphics on a special monitor, while the staff planned to use pixel graphics on a conventional monitor.

The team experimented with recreating the game with pixel graphics, but abandoned it because they felt the gameplay lacked enjoyment and visual appeal. Believing their first attempts to be too derivative, the developers held brainstorming sessions. During a session, they agreed, they felt a game that allowed the player to fly off the screen would be exciting, decided to create a game world larger than the screen displayed. The game's environment was made longer than the screen, with the visible area scrolling horizontally. Expanding on the idea, they envisioned. By changing the orientation of Space Invaders' design, the ship moved up and down while flying horizontally. Large asteroids, an element from Asteroids, were added to the game world, but were removed because the staff felt it lacked enjoyment. Jarvis intended the screen to scroll only from left to right. After six months of development, the team felt, they concluded that survival was a necessary component to implement. To achieve this, they devised enemies to present a threat, the first of, the "Lander".

Jarvis enjoyed violent, action entertainment, wanted the game to have those elements. However, he felt. Inspired by the 1960s television show The Defenders, Jarvis titled the game Defender, reasoning that the title helped justify the violence, he added astronauts to expand on the space theme and give players something to defend while they shot enemies. The element of flying over a planetscape was added after a brainstorming session between Jarvis and Ritchie; the landscape is depicted as a line only a pixel wide because the hardware was not powerful enough to generate anything more detailed. By July, development was behind schedule and Jarvis's superior began to pressure him to finish the game in time for a then-upcoming trade show, the AMOA, in September. Jarvis spent several weeks creating the astronauts, which his boss felt should be omitted if the process didn't speed up; the pressure frustrated him to the point. Around t

United States expedition to Korea

The United States expedition to Korea, known by the Koreans as the Shinmiyangyo or the Korean Expedition, in 1871, was the first American military action in Korea. It took place predominantly around Ganghwa Island; the reason for the presence of the American land and naval force in Korea was to support an American diplomatic delegation sent to establish trade and political relations with the peninsular nation, to ascertain the fate of the merchant ship General Sherman, to establish a treaty assuring aid for shipwrecked sailors. When Korean shore batteries attacked two American warships on June 1, a punitive expedition was launched 10 days after the commanding American admiral failed to receive an official apology from the Koreans; the isolationist nature of the Joseon dynasty government and the assertiveness of the Americans led to a misunderstanding between the two parties that changed a diplomatic expedition into an armed conflict. On June 10, about 650 Americans landed and captured several forts, killing over 200 Korean troops with a loss of only three American dead.

Korea continued to refuse to negotiate with the United States until 1882. The expedition consisted of about 650 men, over 500 sailors and 100 Marines, as well as five warships: Colorado, Palos and Benicia. Embarked aboard Colorado was Rear Admiral John Rodgers Frederick F. Low, the United States Ambassador to China; the Korean forces, known as "Tiger Hunters", were led by General Eo Jae-yeon. The Americans safely made contact with the Korean inhabitants, described as "people wearing white clothes"; when they inquired about the General Sherman incident, the Koreans were reluctant to discuss the topic, ostensibly to avoid having to pay any recompense. The Americans let the Koreans know that their fleet would be exploring the area, that they meant no harm; this gesture was misinterpreted. On June 1, the Korean fortress fired at the U. S. fleet as they sailed up the Ganghwa Straits. The U. S. forces were not badly damaged due to "the bad gunnery of the oreans, whose fire, although hot for the fifteen minutes in which they maintained it, was ill-directed, without effect."

The U. S. demanded an apology within 10 days. On June 10, the Americans attacked the defended Choji Garrison on Ganghwa, along the Salee River; the Koreans were armed with outdated weapons, such as matchlock muskets but with cannons. After they were overrun, the Americans moved onto their next objective, the Deokjin Garrison; the poorly armed Korean forces were kept from effective range by American 12-pound howitzers. The American troops continued on towards the next objective, Deokjin Fort, which they found abandoned; the sailors and Marines dismantled this fortress and continued to Gwangseong Garrison, a citadel. By this time, Korean forces had regrouped there. Along the way, some Korean units tried to flank the U. S. were beaten off again due to the strategic placement of artillery on two hills. Artillery fire from ground forces and Monocacy offshore pounded the citadel in preparation for an assault by U. S. forces. A force of 546 sailors and 105 Marines grouped on the hills west of the fortress keeping cover and returning fire.

Once the bombardment stopped, the Americans charged the citadel, led by Lieutenant Hugh McKee. The slow reload time of the Korean matchlocks aided the Americans, who were armed with superior Remington rolling block carbines, in making it over the walls. McKee was the first to make it into the citadel, was fatally wounded by a shot to the groin. After him came Commander Winfield Scott Schley, who shot the Korean soldier who had killed McKee; the flag of the Korean commander, General Eo Jae-yŏn, called the "Sujagi" by Koreans, was captured by Corporal Charles Brown of Colorado's guard and Private Hugh Purvis of Alaska's guard. General Eo was killed by Private James Dougherty. While serving as the color bearer for Colorado's crew and Marines, Colorado Carpenter Cyrus Hayden planted the U. S. flag on the ramparts under heavy enemy fire. Corporal Brown, Privates Dougherty and Purvis, Carpenter Hayden received the Medal of Honor; the fighting lasted fifteen minutes. The total number of killed were three Americans.

S. Marine Corps Private Denis Hanrahan. 10 Americans were wounded and 20 Koreans were captured, several of whom were wounded. Five Korean forts were taken with dozens of various small cannons; the Korean deputy commander was among the wounded. The U. S. hoped to use the captives as a bargaining chip to meet with local officials, but the Koreans refused, calling the captives cowards and "Low was told that he was welcome to keep the wounded prisoners". Following the military operations of June 10–12, the United States Asiatic Squadron stayed at anchorage off Jakyak Island until July 3, when they left for China; the United States was not able to achieve its objectives diplomatically, as the Koreans refused to negotiate. In fact, these events led the regent Daewon-gun to strengthen his policy of isolation and issue a national proclamation against appeasing foreigners. However, there were no further attacks on foreign ships. In 1876, Korea e

Leucocoprinus fragilissimus

Leucocoprinus fragilissimus known as the fragile dapperling, is a species of gilled mushroom in the family Agaricaceae. The species was first documented by French mycologist Narcisse Théophile Patouillard in 1900; the cap of the fruit body is up to 4.5 cm wide, bell-shaped when young and growing to convex in maturity. It has a pale yellow colour that fades with age, white gills; the narrow stalk is between 1 and 3 mm thick and fragile. Leucocoprinus magnicystidiosus is a similar mushroom, with larger cheilocystidia. Like all Leucocoprinus species, L. fragilissimus is a saprotroph, living on decayed plant matter. It grows solitarily or sparsely in wooded areas; the species is found in southern North America, South America, southern Europe, Africa and eastern Asia and New Zealand. The toxicity of this mushroom is unknown

Dave Van Horne

Dave Van Horne is a Major League Baseball announcer. Van Horne has been the lead play-by-play announcer for the Miami Marlins Radio Network since 2001. After graduating from Wilson Borough High School in 1957, Van Horne entered the drama department at the Richmond Professional Institute in Richmond, Virginia. While at the school he began hosting a Top 40 program at a local radio station, which led to his dropping out of school and starting a full-time broadcasting career in Roanoke, where he began calling high school football and basketball; this led in turn to Van Horne calling baseball for the Richmond Braves, the Class AAA affiliate of the Atlanta Braves, beginning in 1966. He was hired by the Expos for their inaugural season in 1969. Van Horne is well known for his "El Presidente, El Perfecto!" call, made when Montreal Expos pitcher Dennis Martínez completed his perfect game against the Los Angeles Dodgers on July 28, 1991. With the Expos, his sign-in phrase "Thanks Duke and hi again, everybody.

Glad to have you aboard for today's game...", home run call "up, up and away" projected his enthusiasm and excitement. In 2000, as the Expos had not secured an English radio or television contract, Van Horne broadcast the season over the Internet. With the Expos broadcast situation still unsettled for the 2001 season, Van Horne left at the end of 2000 to broadcast for the Marlins. Since 2001, Van Horne has broadcast games for the Marlins. During his time in Florida he called the 2003 World Series championship. Coincidentally enough, Van Horne broadcast the last Expos home game in Montreal from the Marlins' broadcast booth on September 29, 2004—a 9–1 win for Florida. After the game was over, Van Horne joined the Expos television crew for a special post-game show. Van Horne was named the 1996 recipient of the Jack Graney Award by the Canadian Baseball Hall of Fame for "A lifetime of media achievement", he was inducted into the Canadian Baseball Hall of Fame on June 21, 2014, along with former Montreal Expos general manager Murray Cook and third baseman Tim Wallach.

Van Horne is the 2011 recipient of the Ford C. Frick Award from the National Baseball Hall of Fame, he received the award on July 2011 in Cooperstown, New York. Montreal newspaper interview on memories of Expos Ottawa Sun article on the final Expos home series