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❤️ Coober Pedy 🐢

"High-quality Coober Pedy rough opal from the Dead Horse Gully area Coober Pedy () is a town in northern South Australia, north of Adelaide on the Stuart Highway. In the 2016 Census, there were 1,762 people in Coober Pedy (State Suburbs). Of these, 962 were male and 801 were female. There were 302 Aboriginal or Torres Strait Islander people that made up 17.1% of the population. The town is sometimes referred to as the "opal capital of the world" because of the quantity of precious opals that are mined there. Coober Pedy is renowned for its below-ground residences, called "dugouts", which are built in this fashion due to the scorching daytime heat. The name "Coober Pedy" comes from the local Aboriginal term kupa-piti, which means "boys' waterhole".Place Names of South Australia The first opal was found in Coober Pedy on 1 February 1915; since then the town has been supplying most of the world's gem-quality opal. Coober Pedy today relies as much on tourism as the opal mining industry to provide the community with employment and sustainability. Coober Pedy has over 70 opal fields and is the largest opal mining area in the world. Milky Way over Coober Pedy Overview Aboriginal people have a long-standing connection with the area. The first European explorer to pass near the site of Coober Pedy was Scottish-born John McDouall Stuart in 1858. The town was not established until after 1915, when opal was discovered by Wille Hutchison. Miners first moved in about 1916. By 1999, there were more than 250,000 mine shaft entrances in the area and a law discouraged large-scale mining by allowing each prospector a claim.Smith, R. Australia: Journey Through a Timeless Land. National Geographic Society, 1999. p 118. The harsh summer desert temperatures mean that many residents prefer to live in caves bored into the hillsides ("dugouts"). A standard three-bedroom cave home with lounge, kitchen, and bathroom can be excavated out of the rock in the hillside for a similar price to building a house on the surface. However, dugouts remain at a constant temperature, while surface buildings need air conditioning, especially during the summer months, when temperatures often exceed . The relative humidity rarely gets over 20% on these hot days, and the skies are usually cloud-free. The average maximum temperature is , but it can get quite cool in the winter. Coober Pedy is a very small town, about halfway between Adelaide and Alice Springs. It has become a popular stopover point and tourist destination, especially since 1987, when the sealing of the Stuart Highway was completed. Entrance to an underground motel, Coober Pedy, 2007 Coober Pedy underground motel room, 2007. The inverted umbrella in the ceiling catches loose dirt that falls down the ventilation shaft from the surface. Visitors attractions in Coober Pedy include the mines, the graveyard and the underground churches (the Serbian Orthodox Church and the Catholic Church). There are several motels offering underground accommodation, ranging from a few rooms to the entire motel being a dug-out. The hybrid Coober Pedy Solar Power Station supplies power to the off-grid area. Heritage sites Coober Pedy has a number of heritage-listed sites, including: * 13 Hutchison Street: Three-Roomed Dugout * 9 Hutchison Street: Coober Pedy Catholic Church and Presbytery Population The District Council of Coober Pedy estimates the population to be around 2,500. Approximately 60% of the people are of European extraction, migrating from southern and eastern Europe after the Second World War. In all, there are more than 45 nationalities represented. Media Coober Pedy is home to the Coober Pedy Regional Times, a free community publication released fortnightly since 15 March 2001. Under a previous name, it had begun as a newsletter called the Coober Pedy Times, which was first issued in August 1982, itself continuing from a publication known as "Opal Chips". After some financial difficulties, the Times was bought by its editor, Margaret McKay, in 2006 and now includes online versions. Sport and recreation The local golf course – mostly played at night with glowing balls, to avoid daytime heat – is completely free of grass, and golfers take a small piece of "turf" around to use for teeing off. As a result of correspondence between the two clubs, the Coober Pedy golf club is the only club in the world to enjoy reciprocal rights at The Royal and Ancient Golf Club of St Andrews. The town also has an Australian rules football club, the Coober Pedy Saints, established in 2004 and compete in the Far North Football League (formerly the Woomera & Districts Football League). Due to the town's isolation, to play matches the Saints must make round trips of over to Roxby Downs, where the rest of the league's teams are located. The town has a drive- in theatre. It opened in 1965, but became less popular after 1980 with the arrival of television to the town, and ceased regular operation in 1984. It was re-opened in 1996. Climate Coober Pedy has a hot desert climate (Köppen climate classification BWh). Typical of a desert climate, diurnal ranges are wider than in most places, with an annual average high of and an annual average low of just . Summer temperatures range from in the shade, with occasional dust storms. The annual rainfall in the area is low and amongst the lowest in Australia, at around .Coober Pedy Visitor Information Centre > Climate Accessed 13 July 2014.CooberPedy.com.au > Coober Pedy weather Accessed 15 July 2014. Precipitation is well-distributed through the year, although the lowest amounts are recorded in the winter months. Extremes of annual rainfall since 1921 range from in 1929 to in 1973. Coober Pedy was flooded when of rainfall was recorded in 24 hours (which is over three-quarters of the mean annual rainfall) on 10 April 2014. Terrain Coober Pedy – sunset on the breakways Coober Pedy is situated on the edge of the erosional scarp of the Stuart Ranges, on beds of sand and siltstone deep and topped with a stony, treeless desert. Very little plant life exists in town due to the region's low rainfall, high cost of water, sandstone and lack of topsoil. Transport The mail truck to Oodnadatta, 2007 The town is served by daily coach services from Adelaide by Greyhound Australia. The Ghan train serves the town through the Manguri Siding, from Coober Pedy, which is served by trains once weekly in each direction. Passengers on The Ghan are not usually allowed to disembark at Manguri unless they have prearranged transport, due to the siding's isolation and the extremely cold temperatures at night. Coober Pedy is a gateway to the outback communities of Oodnadatta and William Creek, which are both located on the Oodnadatta Track. There is a twice-a-week mail run from Coober Pedy to these communities and other outback homesteads. It carries the mail, general freight and passengers. Regional Express also has direct flights to Adelaide, from Coober Pedy Airport. Minerals Opalised mollusc shell from a Coober Pedy mine In May 2009, South Australian Premier Mike Rann opened the $1.15 billion Prominent Hill Mine, south east of Coober Pedy. The copper-gold mine is operated by OZ Minerals. In August 2010 Rann opened the Cairn Hill iron ore/copper/gold mine operated by IMX Resources near Coober Pedy. It was the first new iron ore mining area opened in South Australia since the 19th century. Due to low iron ore prices, the Cairn Hill mine was closed in June 2014.Cairn Hill iron ore miner IMX Resources to close South Australian office, focus on Tanzanian exploration The Advertiser, 3 September 2014. Accessed 4 September 2014. It was sold to Cu-River Mining who reopened the mine in 2016. Oil reserves In 2013, a potentially significant tight oil (oil trapped in oil-bearing shales) resource was found near the outskirts of Coober Pedy in the Arckaringa Basin. This resource was estimated to hold between of oil, providing the potential for Australia to become a net oil exporter. In popular culture An underground jewellery shop in Coober Pedy Both the town and its hinterland, for different reasons, are photogenic and have attracted film makers. The town itself was the setting for: * Fire in the Stone (1984) * Opal Dream (2006) * Until the End of the World (1991) Its environment has also attracted movie producers, with parts of these movies filmed in the area: * Mad Max 3: Beyond Thunderdome (1985) * Ground Zero (1987) * The Blood of Heroes (1989) * The Adventures of Priscilla – Queen of the Desert (1994) * The Chronicles of Riddick: Pitch Black (2000) * Red Planet (2000) * Kangaroo Jack (2003) * Science Fiction Volume One: The Osiris Child (2016) The town is featured in the 2016 racing game Forza Horizon 3 and is the location of the Horizon Outback Festival. A YouTube video was made by Tom Scott about how he went to the town to see the water, but his plan failed and became a lesson in citations, research and truth. In philately A rare exhibition cachet, signed by Coober Pedy Postmaster Alfred P. North, was discovered in Memphis, Tennessee on 3 February 2016. To date, it is the only known example of this cachet in the world. See also * Kupa Piti Kungka Tjuta References External links * * Official website from The District Council of Coober Pedy & the Coober Pedy Retail Business & Tourism Association * Photographs of Coober Pedy in 1994, National Library of Australia Category:Far North (South Australia) Category:Mining towns in South Australia Category:Underground cities Category:Opals "

❤️ Alexander Henry the elder 🐢

"Alexander Henry 'The Elder' (August 1739 – 4 April 1824) was one of the leading pioneers of the British-Canadian fur trade, following the British Conquest of New France; a partner in the North West Company; and a founding member and vice-chairman of the Beaver Club. In 1763–64, he lived and hunted with Wawatam of the Ojibwa, who had adopted him as a brother. "Blessed with as many lives as a cat," he recounted his time with the Ojibwa and subsequent explorations in his Travels and Adventures in Canada and the Indian Territories between the years 1760 and 1776 (published New York, 1809), which he dedicated to his friend Sir Joseph Banks. The book is considered an adventure classic and one of the best descriptions of Native Indian life at this time. An "easy and dignified" raconteur, in 1776 Henry was invited to give an account of his journeys at the Royal Society in London and at Versailles to Queen Marie Antoinette. In the 1780s, Henry introduced John Jacob Astor into the Canadian fur trade; subsequently Astor would stay as Henry's guest during his annual visits to Montreal. Early life Alexander Henry was born at New Brunswick, New Jersey to an educated merchant family related to Matthew Henry.Pioneers in Canada (2009), by Sir Harry Johnston He was the eldest son of John Henry (d. 1766), a merchant whose father, Alexander Henry (d. 1744), had emigrated to British North America from the West of England to seek his fortune.Red River Ancestry He received a good education and afterward took an apprenticeship in business. From the age of twenty, Henry was working as a merchant out of Albany, New York. He made a lucrative but hazardous living supplying the British army during the French and Indian War (the North American front of the Seven Years' War). In 1760, following Wolfes victory at the Battle of the Plains of Abraham, Henry was placed in charge of three loaded supply bateaux, which followed Lord Amhersts advance along Lake Ontario to Montreal. Henry was the first Englishman known to have visited the area of Milwaukee, in 1760. In early 1761, at Les Cèdres, Henry met former fur trader Jean-Baptiste Leduc, who acquainted him with the rich possibilities of trading at Michilimackinac and around Lake Superior. That spring at Montreal, he secured a fur-trade pass from Major-General Thomas Gage - the second Englishman (by only a few days) to do so. Henry wrote, "proposing to avail myself of the new market, which was thus thrown open to British adventure, I... procured a quantity of goods" and set out on the Ottawa River to Fort Michilimackinac. As he was "altogether a stranger to the commerce in which (he) was engaging," he stopped while still in Canada to hire a guide, Etienne-Charles Campion, an experienced voyageur. Michilimackinac and the Ojibwa Indians In 1761, as they travelled west, Henry was repeatedly warned by the Indians they encountered not to risk his life among the Ojibwe, who remained fiercely loyal to the French. By the time Henry took the warnings seriously, he did not have enough supplies to turn back. He disguised himself as a voyageur and let Campion pass for the proprietor. No one was fooled. When he arrived among the Ojibwe at Michilimackinac, Henry found himself surrounded by sixty of their warriors, "each with his tomahawk in one hand, and scalping knife in the other."Travels and adventures in Canada and the Indian territories, between the years 1760 and 1776 (New York, 1809), by Alexander Henry The imposingly tall war chief Mihnehwehna/Minweweh coldly reminded him that the English may have conquered the French, but they had not conquered the Ojibwe. On taking New France, the English had neglected to make peace with their Indian allies. Having put to use all of his diplomatic skills for which he would become well known, Henry "inwardly endured the tortures of suspense," before Mineweh declared that he admired Henry's bravery for entering their lands. He said since Henry did not come intending to make war, he could "sleep tranquilly" among them. That winter of 1761–62, a minor Ojibwa chief, Wawatam, adopted Henry as a brother. Henry's ability to make friends with both the French and their allied Indians greatly facilitated his trading activities. Between 1762 and 1763, Henry did business at Sault Ste Marie, where he formed friendships with Jean Baptiste Cadotte, Sr. (father of Michel Cadotte) and Sir Robert Davers. However, when they returned to Michilimackinac, Chief Pontiac had already invoked his Indian uprising against British posts in the North West. The Ojibwa warriors famously attacked Fort Michilimackinac. Danvers was killed and Henry, after hiding for a time in the house of Charles Michel de Langlade, was captured by the Ojibwe. On June 6, Henry and three other English prisoners were taken by canoe toward Beaver Island. As they reached Waugoshance Point, an Ottawa appeared and spoke with them, luring them close to land. Many Ottawa sprang from cover and charged the canoe, forcibly removing the four English prisoners, who were taken back to Mackinac. During the ensuing division of the spoils from the fort, Henry ended up as a possession of the Ojibwe leader Minavavana. Fortunately Wawatam intervened and spirited Henry away to his own lodge.Cleland, Charles E., Rites of Conquest: The History and Culture of Michigan's Native Americans (The University of Michigan Press, 1992) p.139 Several days later, when Henry was threatened again, Wawatam came to his rescue and hid him in Mackinac Island's Skull Cave overnight. He lived with the Wawatam and his family for nearly a year, following them on their seasonal moves to hunting and fishing territories in lower Michigan. Henry's experiences during this winter of 1763–64, described in his memoirs, are a valuable primary source into Native American life during the fur trade era. They returned to Michilimackinac in the spring of 1764 to trade their furs, but some of the Ojibwas from Saginaw Bay plotted to kill Henry and Wawatam permitted him to go to Sault Ste Marie to seek the protection of Cadotte. He was still not safe as another Ojibwa chief, Madjeckewiss, followed him there with some of his warriors intent on killing him, and it took Cadotte's diplomatic skills to dissuade them. Soon after this, at last Sir William Johnson held a peace conference at Fort Niagara and both Henry and the Ojibwas attended. Eager to return to Michilimackinac to recover his property, Henry accompanied the expedition of Colonel John Bradstreet from Niagara to Detroit, and from there he went with Captain William Howard's troops who reoccupied Michilimackinac in September, 1764."Biographical sketch of the late Alexander Henry, esq.," Canadian Magazine and Literary Repository (Montreal), 2 (January–June 1824) Lake Superior and the Canadian North West A Canadian fur trader in 1777 In 1765, Henry acquired a license to trade in the Lake Superior region. Combining British capital with French Canadian experience, he formed a partnership with Cadot. For the next few years Henry was able to maintain a complete monopoly over the Lake Superior trade and without competition he was able to charge exorbitant prices.The Grand Portage Story There he also came into contact with the Frontiersman Robert Rogers, though Henry reported that Rogers never paid him for certain services rendered. In 1767–68 he wintered on the Michipicoten River and entered into a partnership with Sir William Johnson, the Duke of Gloucester and others, forming a company to mine silver found in copper ore on the shores of Lake Superior. The expenses involved made the venture unprofitable and the company wound up its affairs in 1774.Mich. Pioneer Coll. The papers of Sir William Johnson, ed. James Sullivan et al. (14v., Albany, N.Y., 1921–65) In 1775, Henry took four large and twelve small canoes to explore the territory northwest of Lake Superior. Henry, Cadot, Peter Pond, the brothers Thomas and Joseph Frobisher then began to challenge the Hudson's Bay Company. Their group, with forty men, stopped at Cumberland House and afterwards built a trading post on Amisk Lake, the first post to be built north of the Saskatchewan River.Encyclopedia of Saskatchewan In 1776, Henry set off by foot to Fort à la Corne, following the Saskatchewan River, and having satisfied his curiosity secured some furs from the Assiniboines. He then purchased 12,000 additional beaver skins from a trip up the Churchill River from the Chipewyans, and some of his last packs were forcibly acquired from Robert Longmoor, an agent for the Hudson's Bay Company. Laden with furs, Henry returned to Montreal and gave the governor, Sir Guy Carleton, a large map of the western region through which he had travelled. England and France Henry's imagination was caught by the rich potential of the Northwest Territories and he sailed to England in the autumn of 1776 with a proposal for the Hudson's Bay Company. Bearing a Letter of introduction from Luc de la Corne to his brother Abbé Joseph-Marie de La Corne de Chaptes, Henry next went to France where he was met with "a most flattering reception".Travels & Adventures in Canada and the Indian Territories Between the Years 1760 and 1776 Through the influence of the Abbé, Henry was received by Marie-Antoinette at the French Court. Though a natural raconteur who was used to winning friends with ease, it was a great sadness to Henry for the rest of his days that he was met with nothing other than condescension from the young queen and her court.Introduction to Travels & Adventures in Canada and the Indian Territories Between the Years 1760 and 1776 Henry returned to British North America in 1777 in partnership with Jean-Baptiste Blondeau, trading at the Michipicoten River and Sault Ste Marie; all the time working closely with his old friend Cadot. Between 1778 and 1781 he visited England three times, developing friendships with Sir Joseph Banks and Daniel Solander. Having discussed the possibility at Banks' residence on Soho Square with him and Solander, on his last trip to England, Henry delivered a detailed plan to Banks for an expedition to find an overland route to the Pacific Ocean. This had seemed possible when they had studied Captain Cook's recent findings, but as it was, Cook had made a mistake so the planned expedition came to nothing. Montreal, the Chinese Fur Trade and the Cuyahoga Purchase Henry had made a prominent name for himself, and from 1781 he settled in Montreal as a general merchant. He was still very much attached to the fur trade with occasional trips made to Detroit or Michilimackinac, and particularly the latter when he sustained heavy losses following the conclusion of the American Revolution. In 1785, Henry with seventeen of the other most prominent fur traders was a founding member of the Beaver Club at Montreal. During the mid-1780s Henry encouraged a friend in New York, William Edgar (1736–1820), to enter the trade in furs with China. Fascinated by the prospects offered by the Pacific coast, Henry passed on his ideas, which he called "my favorite plan," to New York merchant John Jacob Astor. He introduced Astor into the Canadian trade and Astor was Henry's guest during his annual visits to Montreal. In the 1790s, Henry and Astor assisted Simon McTavish and the North West Company in organizing shipments of furs to China. In 1792, a fur trade partnership between John Forsyth, Jacob Jordan and Alexander Ellice attempted to entice Henry and Peter Pond to join them in opposition to the North West Company. During the 1790s, Henry and another close friend, John Askin, were interested in land speculation in Ohio. One of their ventures, known as the Cuyahoga Purchase, came to naught when the Ohio Indians from whom the land had been acquired at the end of the Northwest Indian War refused to bring forth their land claims at the Treaty of Greenville. The deeds which had been obtained by Henry and his associates were considered invalid, causing Henry to moan, "We have lost a fortune of at least one million of dollars."Alexander Henry to William Edgar, 11 Aug. 1784–22 Oct. 1787 (typescripts) Later Years at Montreal The portrait of Alexander Henry (1739–1824) from his 1809 book Nelson's Column, Montreal. Erected in 1809, Henry was one of the principal donators. In 1792, Henry and his nephew Alexander Henry the younger together obtained one share in the North West Company for six years. In 1796 he sold his interest to William Hallowell (1771–1838), but continued to buy furs from traders and export them to England. When one of his uninsured shipments was captured by the French in 1801, he suffered a serious financial crisis. In order to repair his fortunes, Henry became a commission merchant and auctioneer in partnership with William Lindsay. Plagued by ill health, he worked hard at a job he did not find satisfying. Despite these reverses of fortune, Henry maintained a secure place in Montreal's mercantile society. He served as a captain in the militia and from 1794 to 1821 as justice of the peace. He lavishly entertained leading merchants in his home, regularly signed petitions and memorials, and attended parties. He was particularly active in the Beaver Club, reactivated in 1807, of which he was the senior member and on its creation, the vice-chairman. In 1806, he was one of the principal donators to the building of Nelson's Column, Montreal. In 1812, he was appointed vendue master and King's Auctioneer for the district of Montreal, working in partnership with his nephew Norman Bethune, who lived with him at 14 Rue Saint-Urbain. He remained close to his old friends, and Isaac Todd, who Henry enjoyed teasing, returned again to Montreal from his native Ireland to be close to Henry and McGill. In 1809, Henry had written to Askin, "There is only us four old friends (James McGill, Isaac Todd, Joseph Frobisher, and himself) alive, all the new North westards are a parcel of boys and upstarts, who were not born in our time, and supposes they know much more of the Indian trade than any before them." To recapture his exciting past, he wrote a memoir of his life which he published in New York that year and dedicated to his English friend, Sir Joseph Banks. Travels and Adventures in Canada and the Indian Territories, between the years 1760 and 1776 has become a Canadian adventure classic and is still considered as one of the best descriptions of Native Indian life at the time of Henry's travels. "A middle-sized man, easy yet dignified", Henry was known among the Indians and the French as "the handsome Englishman." He never recovered the wealth he had amassed during the height of the fur trade, but is remembered for his accomplishments in society and as one of the most important business leaders who turned Montreal into an innovative centre of business expansion. At age 85, he died at his home on Notre-Dame Street, Montreal, "esteemed by all who knew him". Family Mrs Julia (born Calcutt) Kittson Henry (1756–1835) As was the custom with early fur traders, Henry had taken a 'country wife', a Native Indian whose sister was in the same way married to Simon McTavish. By her he was said to have fathered several children, but only one daughter is recorded.The Veil surrounding Alexander Henry's Mixed Blood Sons In 1785, having by then returned to society at Montreal, he married Julia Calcutt Kittson (1756–1835), "a woman of considerable personal fortitude". She was a native of Limavady and the widow of an Anglo-Irish army officer, John George Kittson (d. 1779), whose home was in Co. Cork but had seen considerable service in North America. Mrs Julia Henry was the godparent with Sir Isaac Brock of William McGillivray's youngest daughter. It is open to debate whether Julia and Alexander met in Canada, England or Ireland around 1780, but they were the parents of several children, two of whom were born before they were married. Henry was step-father to two Kittsons, and the father of six known children, *Martha Henry (1777–1849), natural daughter by Henry's country wife.Genealogical notes on Henrys, Hallowells and Bethunes At Albany, New York, 1798, she married William Hallowell (1771–1838), who had purchased his partnership into the North West Company from Henry that year. Their daughter, Elizabeth, married John Bethune, Dean of Montreal. *Mary Kittson, Henry's stepdaughter, married to John Cates, brother of Lt. Samuel Cates of the King's Royal Rifle Corps whose wife (Mary Tucker) was the sister of Mrs George Kittson.London Gazette, 1790 *George Kittson (1779–1832), Henry's stepson, married Anne Tucker and was the father of several children including Norman Kittson. Their daughter, Margaret, married Henry's business partner in later life, Norman Bethune (1789–1848), son of Rev. John Bethune. Another son, William Henry Kittson, married a sister of Chief Justice Sir William Collis Meredith. Meredith's former business partner at Montreal, Strachan Bethune, was the grandson of George Kittson's sister, Martha (Henry) Hallowell. *Julia Henry (b.1780), died unmarried. *William Henry (1784–1864), was a fur trader with the North West Company and later a surveyor and civil engineer at Montreal. He carried several scars from knife wounds received in quarrels with various Indians, and in the Rocky Mountains he had his scalp torn off by a Grizzly bear before being rescued by an Indian. He was inducted into the Beaver Club in 1817. He was married to Jane Doe Felton, sister of The Hon. William Bowman Felton. They had several children including Charles Henry (1832–1897), who ran away from home at the age of thirteen to lead an adventurous life on the seas which included being shipwrecked on one of the islands off Hawaii, for a brief period, where he was married to a native. *Alexander Henry (1785–1812), not be confused with his first cousin Alexander Henry the younger. He also worked for the North West Company, but was "barbarously murdered" by Native Indians at Fort Nelson near Port Nelson, Manitoba. *Robert Henry (born after 1785-), wintering partner of the North West Company and director of the Commercial Bank of the Midland District at Cobourg. He was inducted into the Beaver Club in 1815. He married Christine Bethune (1787–1865), daughter of Rev John Bethune.John Bethune of Glengarry *John Henry (1786–1787), died an infant. His godparents were Mrs Isaac Todd and Mrs John Gregory, wives of two of the earliest and most prominent partners of the North West Company. External links *Alexander Henry and the Grand Portage Story at the NPS *Henry's story of capture at Fort Michilimackinac *The Veil surrounding Alexander Henry's Mixed Blood Sons References Category:1739 births Category:1824 deaths Category:American fur traders Category:Canadian fur traders Category:Pedlars (fur trade) Category:Writers from Montreal Category:Writers from New Brunswick, New Jersey Category:Captives of Native Americans Category:Writers of captivity narratives Category:Persons of National Historic Significance (Canada) Category:19th- century Canadian non-fiction writers Category:Canadian justices of the peace "

❤️ Starspot 🐢

"Starspots are stellar phenomena, so-named by analogy with sunspots. Spots as small as sunspots have not been detected on other stars, as they would cause undetectably small fluctuations in brightness. The commonly observed starspots are in general much larger than those on the Sun: up to about 30% of the stellar surface may be covered, corresponding to starspots 100 times larger than those on the Sun. Detection and measurements To detect and measure the extent of starspots one uses several types of methods. *For rapidly rotating stars – Doppler imaging and Zeeman-Doppler imaging.Cameron 2008 With the Zeeman-Doppler imaging technique the direction of the magnetic field on stars can be determined since spectral lines are split according to the Zeeman effect, revealing the direction and magnitude of the field. *For slowly rotating stars – Line Depth Ratio (LDR). Here one measures two different spectral lines, one sensitive to temperature and one which is not. Since starspots have a lower temperature than their surroundings the temperature-sensitive line changes its depth. From the difference between these two lines the temperature and size of the spot can be calculated, with a temperature accuracy of 10K. *For eclipsing binary stars – Eclipse mapping produces images and maps of spots on both stars.Cameron 2008. Eclipse movies show spots on two imaged binaries *For stars with transiting extrasolar planets – Light curve variations. Temperature Observed starspots have a temperature which is in general 500–2000 kelvins cooler than the stellar photosphere. This temperature difference could give rise to a brightness variation up to 0.6 magnitudes between the spot and the surrounding surface. There also seems to be a relation between the spot temperature and the temperature for the stellar photosphere, indicating that starspots behave similarly for different types of stars (observed in G–K dwarfs). Lifetimes The lifetime for a starspot depends on its size. *For small spots the lifetime is proportional to their size, similar to spots on the Sun.Berdyugina 5.3 Lifetimes *For large spots the sizes depend on the differential rotation of the star, but there are some indications that large spots which give rise to light variations can survive for many years even in stars with differential rotation. Activity cycles The distribution of starspots across the stellar surface varies analogous to the solar case, but differs for different types of stars, e.g., depending on whether the star is a binary or not. The same type of activity cycles that are found for the Sun can be seen for other stars, corresponding to the solar (2 times) 11-year cycle. Some stars have longer cycles, possibly analogous to the Maunder minima for the Sun. =Flip-flop cycles= Another activity cycle is the so-called flip-flop cycle, which implies that the activity on either hemisphere shifts from one side to the other. The same phenomena can be seen on the Sun, with periods of 3.8 and 3.65 years for the northern and southern hemispheres. Flip-flop phenomena are observed for both binary RS CVn stars and single stars although the extent of the cycles are different between binary and singular stars. Notes References * (explains how Doppler imaging works) * * K. G. Strassmeier (1997), Aktive Sterne. Laboratorien der solaren Astrophysik, Springer, Further reading * Category:Stellar phenomena "

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