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46-556: The SMC is visible from the entire Southern Hemisphere and can be fully glimpsed low above the southern horizon from latitudes south of about 15° north . The galaxy is located across the constellation of Tucana and part of Hydrus , appearing as a faint hazy patch resembling a detached piece of the Milky Way . The SMC has an average apparent diameter of about 4.2° (8 times the Moon's) and thus covers an area of about 14 square degrees (70 times

92-573: A Human Development Index (HDI) of 0.946, the tenth-highest in the world as of the 2024 report. New Zealand is also well developed, with a nominal GDP per capita of US$ 48,072 and an HDI of 0.939, putting it at number 16 in the world in 2024. The least developed nations in the Southern Hemisphere cluster in Africa and Oceania, with Mozambique and Burundi at the lowest ends of the HDI, at 0.461 (number 183 in

138-446: A HMXRB, is at J2000 right ascension (RA) 01 15 14 declination (Dec) 73° 42′ 22″. Two additional sources detected and listed in 3A include SMC X-2 at 3A 0042-738 and SMC X-3 at 3A 0049-726. It has been proposed by astrophysicists D. S. Mathewson, V. L. Ford and N. Visvanathan that the SMC may in fact be split in two, with a smaller section of this galaxy behind

184-511: A chemist in St. Petersburg, in 1901 he studied photochemistry at Leipzig University for a year. His father was an amateur astronomer, which led to Ejnar's interest in the subject. He began making astronomical observations in Frederiksberg in 1902, and within a few years had noticed that stars with similar spectral type could have widely different absolute magnitudes . In 1909, he took a position at

230-557: A long time. In 2017, using the Dark Energy Survey plus MagLiteS data, a stellar over-density associated with the Small Magellanic Cloud was discovered, which is probably the result of interactions between the SMC and LMC. The Small Magellanic Cloud contains a large and active population of X-ray binaries . Recent star formation has led to a large population of massive stars and high-mass X-ray binaries (HMXBs) which are

276-633: A mistake, possibly a slip of the pen, putting the stars 10 times too close. He used this relationship to estimate the distance to the Small Magellanic Cloud . From 1919 to 1946, Hertzsprung worked at Leiden Observatory in the Netherlands, from 1937 as director. Among his graduate students at Leiden was Gerard Kuiper . Perhaps his greatest contribution to astronomy was the development of a classification system for stars to divide them by spectral type, stage in their development, and luminosity. He used

322-469: A type of variable star called a "cluster variable", later called a Cepheid variable after the prototype star Delta Cephei , showed a definite relationship between the variability period and the star's apparent brightness. Leavitt realized that since all the stars in the SMC are roughly the same distance from Earth, this result implied that there is similar relationship between period and absolute brightness. This important period-luminosity relation allowed

368-479: Is mostly concentrated on/around the islands of Bali , Mauritius , and Fiji . The oldest continuously inhabited city in the Southern Hemisphere is Bogor , in western Java , which was founded in 669 . Ancient texts from the Hindu kingdoms prevalent in the area definitively record 669 CE as the year when Bogor was founded. However, some evidence shows that Zanzibar , an ancient port with around 200,000 inhabitants off

414-624: Is native to Australia but is now also planted in Southern Africa and Latin America for pulp production, and increasingly, biofuel uses. One of the most notable animals to be found almost exclusively in the Southern Hemisphere is the penguin . A species is found around Isabela Island on the Galápagos archipelago in the Pacific Ocean , which straddles the equator. However, most of Isabela and

460-570: Is the half ( hemisphere ) of Earth that is south of the Equator . It contains all or parts of five continents (the whole of Antarctica , the whole of Australia , about 90% of South America , about one-third of Africa , and some islands off the continental mainland of Asia ) and four oceans (the whole Southern Ocean , the majority of the Indian Ocean , the South Atlantic Ocean , and

506-738: Is the vernal equinox and March 20 or 21 is the autumnal equinox. The South Pole is in the centre of the southern hemispherical region. Southern Hemisphere climates tend to be slightly milder than those at similar latitudes in the Northern Hemisphere , except in the Antarctic which is colder than the Arctic . This is because the Southern Hemisphere has significantly more ocean and much less land; water heats up and cools down more slowly than land. The differences are also attributed to oceanic heat transfer and differing extents of greenhouse trapping. In

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552-742: The Age of Discovery , the Southern Hemisphere was largely cut off from the cultural constructs of the Western and Eastern worlds . Some view both the West and the East as being Northern Hemisphere-centric concepts. The most widespread religions in the modern Southern Hemisphere are Christianity , prevalent in South America, Africa, Oceania, and East Timor , followed by Islam in East Africa and Indonesia , and Hinduism , which

598-569: The Göttingen Observatory under director Karl Schwarzschild . In 1911 Hertzsprung developed the Hertzsprung–Russell diagram , independently developed in 1913 by Henry Norris Russell . In 1913 Hertzsprung determined the distances to several Cepheid variable stars by parallax , and was thus able to calibrate the relationship, discovered by Henrietta Leavitt , between Cepheid period and luminosity . In this determination he made

644-475: The Norte Chico civilization and Casma–Sechin culture from the northern coast of Peru. These civilizations built cities, pyramids, and plazas in the coastal river valleys of northern Peru with some ruins dating back to 3600 BCE . Easter Island , located about 3,500 kilometres from Chile and French Polynesia , is considered to be the most remote place on Earth to have been permanently inhabited by humans before

690-644: The South Pacific Ocean ), as well as New Zealand and most of the Pacific Islands in Oceania . Its surface is 80.9% water, compared with 60.7% water in the Northern Hemisphere , and it contains 32.7% of Earth's land. Owing to the tilt of Earth's rotation relative to the Sun and the ecliptic plane , summer is from December to February (inclusive) and winter is from June to August (inclusive). September 22 or 23

736-479: The constellation Tucana : 4U 0115-73 (3U 0115-73, 2A 0116-737, SMC X-1). Uhuru observed the SMC on January 1, 12, 13, 16, and 17, 1971, and detected one source located at 01149-7342, which was then designated SMC X-1. Some X-ray counts were also received on January 14, 15, 18, and 19, 1971. The third Ariel 5 catalog (3A) also contains this early X-ray source within Tucana: 3A 0116-736 (2A 0116-737, SMC X-1). The SMC X-1,

782-745: The Age of Discovery. It was settled by a Polynesian group known as the Rapa Nui . Areas of the Southern Hemisphere that had no contact with humans before the Age of Discovery include Christmas Island and Mauritius (in the Indian Ocean ), the Galápagos Islands , Juan Fernández Islands and Lord Howe Island (in the South Pacific), the Falkland Islands and Tristan da Cunha (in the South Atlantic ) and

828-559: The Cape Clouds, a name that was retained for several centuries. During the circumnavigation of the Earth by Ferdinand Magellan in 1519–1522, they were described by Antonio Pigafetta as dim clusters of stars. In Johann Bayer 's celestial atlas Uranometria , published in 1603, he named the smaller cloud, Nubecula Minor. In Latin , Nubecula means a little cloud. Between 1834 and 1838, John Frederick William Herschel made observations of

874-571: The Magellanic clouds have long been included in the lore of native inhabitants, including south sea islanders and indigenous Australians . Persian astronomer Al Sufi mentions them in his Book of Fixed Stars , repeating a quote by the polymath Ibn Qutaybah , but had not observed them himself. European sailors may have first noticed the clouds during the Middle Ages when they were used for navigation. Portuguese and Dutch sailors called them

920-582: The Moon moves from right to left during solar eclipses. The Coriolis effect causes cyclones and tropical storms to spin clockwise in the Southern Hemisphere, as opposed to anticlockwise in the Northern Hemisphere. The southern temperate zone , a subsection of the Southern Hemisphere, is nearly all oceanic. The Sagittarius constellation that includes the galactic centre is a southern constellation as well as both Magellanic Clouds . This, combined with clearer skies, makes for excellent viewing of

966-627: The Moon's). Since its surface brightness is very low, this deep-sky object is best seen on clear moonless nights and away from city lights . The SMC forms a pair with the Large Magellanic Cloud (LMC), which lies 20° to the east, and, like the LMC, is a member of the Local Group . It is currently a satellite of the Milky Way, but is likely a former satellite of the LMC. In the southern hemisphere,

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1012-420: The SMC performed with NASA's Rossi X-ray Timing Explorer (RXTE) see X-ray pulsars in outburst at more than 10 erg/s and have counted 50 by the end of 2008. The ROSAT and ASCA missions detected many faint X-ray point sources, but the typical positional uncertainties frequently made positive identification difficult. Recent studies using XMM-Newton and Chandra have now cataloged several hundred X-ray sources in

1058-480: The SMC. The Be-star equatorial disk provides a reservoir of matter that can be accreted onto the neutron star during periastron passage (most known systems have large orbital eccentricity) or during large-scale disk ejection episodes. This scenario leads to strings of X-ray outbursts with typical X-ray luminosities L x  = 10–10  erg /s, spaced at the orbital period, plus infrequent giant outbursts of greater duration and luminosity. Monitoring surveys of

1104-408: The Southern Hemisphere include Bali , Buenos Aires , Cape Town , Easter Island , Lima , Rio de Janeiro , Sydney and Tahiti . According to a 2017 report, the most popular Southern Hemisphere " bucket list " destinations among Australians were Antarctica , New Zealand , the Galápagos Islands , South Africa and Peru . Quito, Ecuador is the closest major city to the equatorial line on

1150-745: The Southern Hemisphere include São Paulo , where the B3 (stock exchange) is headquartered, along with Sydney, home to the Australian Securities Exchange , Jakarta, the seat of the Indonesia Stock Exchange , Johannesburg , home to the Johannesburg Stock Exchange , and Buenos Aires, headquarters of the Buenos Aires Stock Exchange , the oldest stock market in the Southern Hemisphere. Common tourist destinations in

1196-514: The Southern Hemisphere, the Sun passes from east to west through the north, although north of the Tropic of Capricorn the mean Sun can be directly overhead or due south at midday. The Sun follows a right-to-left trajectory through the northern sky unlike the left-to-right motion of the Sun when seen from the Northern Hemisphere as it passes through the southern sky. Sun-cast shadows turn anticlockwise throughout

1242-512: The coast of Tanzania , may be older than Bogor. A Greco-Roman text written between 1 and 100 CE , the Periplus of the Erythraean Sea , mentioned the island of Menuthias ( Ancient Greek : Μενουθιάς) as a trading port on the east African coast, which is probably the small Tanzanian island of Unguja on which Zanzibar is located. The oldest monumental civilizations in the Southern Hemisphere are

1288-569: The continent of Antarctica . Entirely — Partly — Entirely — Partly — Entirely — Mostly — Partly — Entirely — Ejnar Hertzsprung Ejnar Hertzsprung ( Danish: [ˈɑjnɐ ˈhɛɐ̯tsˌpʁɔŋ] ; 8 October 1873 – 21 October 1967) was a Danish chemist and astronomer. Hertzsprung was born in Frederiksberg , Denmark, the son of Severin and Henriette. He studied chemical engineering at Copenhagen Polytechnic Institute , graduating in 1898. After spending two years working as

1334-521: The day and sundials have the hours increasing in the anticlockwise direction. During solar eclipses viewed from a point to the south of the Tropic of Capricorn, the Moon moves from left to right on the disc of the Sun (see, for example, photos with timings of the solar eclipse of November 13, 2012 ), while viewed from a point to the north of the Tropic of Cancer (i.e., in the Northern Hemisphere),

1380-522: The direction of Solon Bailey , the 24-inch (610 mm) telescope at this site was used to survey photographically both the Large and Small Magellanic Clouds. Henrietta Swan Leavitt , an astronomer at the Harvard College Observatory , used the plates from Arequipa to study the variations in relative luminosity of stars in the SMC. In 1908, the results of her study were published, which showed that

1426-524: The direction of the SMC, of which perhaps half are considered likely HMXBs, and the remainder a mix of foreground stars, and background AGN. No X-rays above background were observed from the Magellanic Clouds during the September 20, 1966, Nike-Tomahawk flight. Balloon observation from Mildura, Australia, on October 24, 1967, of the SMC set an upper limit of X-ray detection. An X-ray astronomy instrument

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1472-416: The distance to any other cepheid variable to be estimated in terms of the distance to the SMC. She hoped a few Cepheid variables could be found close enough to Earth so that their parallax , and hence distance from Earth, could be measured. This soon happened, allowing Cepheid variables to be used as standard candles , facilitating many astronomical discoveries. Using this period-luminosity relation, in 1913

1518-422: The distance to the SMC was first estimated by Ejnar Hertzsprung . First he measured thirteen nearby cepheid variables to find the absolute magnitude of a variable with a period of one day. By comparing this to the periodicity of the variables as measured by Leavitt, he was able to estimate a distance of 10,000 parsecs (30,000 light years) between the Sun and the SMC. This later proved to be a gross underestimate of

1564-573: The earlier classification system developed by Antonia Maury in his work. The so-called "Hertzsprung–Russell Diagram" has been used ever since as a classification system to explain stellar types and stellar evolution . He also discovered two asteroids , one of which is 1627 Ivar , an Amor asteroid . His wife Henrietta (1881–1956) was a daughter of the Dutch astronomer Jacobus Kapteyn . Hertzsprung died in Roskilde in 1967. The asteroid 1693 Hertzsprung

1610-507: The largest country by land area in the Southern Hemisphere, while more than 150 million live in Java , the most populous island in the world. The most populous country in the Southern Hemisphere is Indonesia , with 275 million people (roughly 30 million of whom live north of the Equator on the northern portions of the islands of Sumatra , Borneo , and Sulawesi , as well as most of North Maluku , while

1656-589: The main part of the SMC (as seen from Earth perspective), and separated by about 30,000 ly. They suggest the reason for this is due to a past interaction with the LMC that split the SMC, and that the two sections are still moving apart. They dubbed this smaller remnant the Mini Magellanic Cloud. In 2023, it was reported that the SMC is indeed two separate structures with distinct stellar and gaseous chemical compositions, separated by around 5 kiloparsecs. Southern Hemisphere The Southern Hemisphere

1702-401: The night sky from the Southern Hemisphere with brighter and more numerous stars. Forests in the Southern Hemisphere have special features which set them apart from those in the Northern Hemisphere. Both Chile and Australia share, for example, unique beech species or Nothofagus , and New Zealand has members of the closely related genera Lophozonia and Fuscospora . The eucalyptus

1748-476: The planet, and Ushuaia, Argentina claims the title of world's southernmost city. Cape Town, Christchurch , Hobart , Punta Arenas and Ushuaia are officially acknowledged as the five international Antarctic gateway cities that serve as primary entry points for travel to the Antarctic region. Among the most developed nations in the Southern Hemisphere is Australia, with a nominal GDP per capita of US$ 63,487 and

1794-464: The relics of the short-lived upper end of the initial mass function . The young stellar population and the majority of the known X-ray binaries are concentrated in the SMC's Bar. HMXB pulsars are rotating neutron stars in binary systems with Be-type ( spectral type 09-B2, luminosity classes V–III) or supergiant stellar companions. Most HMXBs are of the Be type which account for 70% in the Milky Way and 98% in

1840-659: The rest of the archipelago is located in the Southern Hemisphere, and it is deemed by the International Hydrographic Organization as being wholly within the South Pacific Ocean, rather than the North Pacific. More than 850 million people live in the Southern Hemisphere, representing around 10–12% of the total global human population. Of those 850 million people, more than 203 million live in Brazil ,

1886-1040: The rest of the population lives in the Southern Hemisphere). Portuguese is the most spoken language in the Southern Hemisphere, with over 230 million speakers in six countries – mostly in Brazil, but also in Angola , Mozambique , East Timor , and small parts of Equatorial Guinea and São Tomé and Príncipe that lie south of the Equator . Among the largest metropolitan areas in the Southern Hemisphere are Jakarta (34 million people), São Paulo (22 million), Kinshasa-Brazzaville (19 million), Buenos Aires (16 million), Rio de Janeiro (12 million), Johannesburg , Lima (11 million each), Surabaya (10 million), Bandung (9 million), Luanda (8 million), Dar es Salaam , Santiago (7 million each), Belo Horizonte , Semarang (6 million each), Sydney , Melbourne and Cape Town (5 million each). Important financial and commercial centres in

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1932-579: The southern skies with his 14-inch (36 cm) reflector from the Royal Observatory . While observing the Nubecula Minor, he described it as a cloudy mass of light with an oval shape and a bright center. Within the area of this cloud he catalogued a concentration of 37 nebulae and clusters. In 1891, Harvard College Observatory opened an observing station at Arequipa in Peru . Between 1893 and 1906, under

1978-530: The true distance, but it did demonstrate the potential usefulness of this technique. Announced in 2006, measurements with the Hubble Space Telescope suggest that either the Large and Small Magellanic Clouds may be moving too fast to be orbiting the Milky Way , or that the Milky Way Galaxy is more massive than was thought. The SMC contains a central bar structure, and astronomers speculate that it

2024-529: The world) and 0.420 (number 187 in the world), respectively. The nominal GDPs per capita of these two countries do not go above US$ 650, a tiny fraction of the incomes enjoyed by Australians and New Zealanders. The Southern Hemisphere has long been secondary in the global distribution of demographic, economic and political power, as it has less land than the Northern Hemisphere. In recent times, however, countries such as Australia have made greater efforts to economically engage with those from their hemisphere. Before

2070-424: Was carried aboard a Thor missile launched from Johnston Atoll on September 24, 1970, at 12:54 UTC for altitudes above 300 km, to search for the Small Magellanic Cloud. The SMC was detected with an X-ray luminosity of 5 × 10 erg/s in the range 1.5–12 keV, and 2.5 × 10 erg/s in the range 5–50 keV for an apparently extended source. The fourth Uhuru catalog lists an early X-ray source within

2116-494: Was once a barred spiral galaxy that was disrupted by the Milky Way to become somewhat irregular . There is a bridge of gas connecting the Small Magellanic Cloud with the Large Magellanic Cloud (LMC), which is evidence of tidal interaction between the galaxies. This bridge of gas is a star-forming site. The Magellanic Clouds have a common envelope of neutral hydrogen, indicating they have been gravitationally bound for

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