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Antipodes

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For other uses, see Antipode (disambiguation).
This map shows the antipodes of each point on the Earth's surface—the points where the blue and yellow overlap are land antipodes—most land has its antipodes in the ocean. This map uses the Lambert azimuthal equal-area projection. The yellow areas can be considered to be opposite reflections of the blue areas but on the inner "surface" of the globe of the Earth
The same map, from the perspective of the Western Hemisphere. Here the blue areas can be considered to be opposite reflections of the yellow areas but on the inner "surface" of the globe of the Earth

In geography, the antipodes (/ænˈtɪpədiːz/; from Greek: ἀντίποδες,[1] from anti- "opposed" and pous "foot") of any place on Earth is the point on the Earth's surface which is diametrically opposite to it. Two points that are antipodal /ænˈtɪpədəl/ to each other are connected by a straight line running through the centre of the Earth.

In the Northern Hemisphere, "the Antipodes" is often used to refer to Australia and New Zealand, and "Antipodeans" to their inhabitants.[2] Geographically the antipodes of Britain and Ireland are in the Pacific Ocean, south of New Zealand. This gave rise to the name of the Antipodes Islands of New Zealand, which are close to the antipodes of London at about 50° S 179° E. The antipodes of Australia are in the North Atlantic Ocean, while parts of Spain, Portugal, and Morocco are antipodal to New Zealand.

All together, between 4%[3] and 27%[4] of land is antipodal to land, depending on how tidal flows are measured.[5] The largest antipodal land masses are the Malay Archipelago, antipodal to the Amazon Basin and adjoining Andean ranges; east China and Mongolia, antipodal to Chile and Argentina; and Greenland and the Canadian Arctic Archipelago, antipodal to East Antarctica.

Geography

The antipodes of any place on the Earth is the place that is diametrically opposite it, so a line drawn from the one to the other passes through the centre of the Earth and forms a true diameter. For example, the antipodes of New Zealand's lower North Island lies in Spain. Most of the Earth's land surfaces have ocean at their antipodes, this being a consequence of most land being in the land hemisphere.

An antipodal point is sometimes called an antipode, a back-formation from the plural antipodes, which in Greek is the plural of the singular antipous.

The antipodes of any place on Earth are distant from it by 180° of longitude and as many degrees to the north of the equator as the original is to the south (or vice versa); in other words, the latitudes are numerically equal, but one is north and the other south. The map shown above is based on this relationship; it shows a Lambert azimuthal equal-area projection map of the Earth, in yellow, overlaid on which is another map, in blue, shifted horizontally by 180° of longitude and inverted about the equator with respect to latitude.

Noon at the one place is midnight at the other (ignoring daylight saving and irregularly shaped time zones) and, with the exception of the tropics, the longest day at one point corresponds to the shortest day at the other, and midwinter at one point coincides with midsummer at the other. Sunrise and sunset do not quite oppose each other at antipodes due to refraction of sunlight.

Mathematical description

If the geographic coordinates (latitude and longitude) of a point on the Earth’s surface are (φ, θ), then the coordinates of the antipodal point are (−φ, θ ± 180°). This relation holds true whether the Earth is approximated as a perfect sphere or as a reference ellipsoid.

In terms of the usual way these geographic coordinates are given, this transformation can be expressed symbolically as

x° N/S y° E/W  ↦  x° S/N (180 − y)° W/E,

that is, for the latitude (the North/South coordinate) the magnitude of the angle remains the same but N is changed to S and vice versa, and for the longitude (the East/West coordinate) the angle is replaced by its supplementary angle while E is exchanged for W. For example, the antipodes of the point in China at 37° N 119° E (a few hundred kilometres from Beijing) is the point in Argentina at 37° S 61° W (a few hundred kilometres from Buenos Aires).

Etymology

The Greek word is attested in Plato's dialogue Timaeus, already referring to a spherical Earth, explaining the relativity of the terms "above" and "below":

For if there were any solid body in equipoise at the centre of the universe, there would be nothing to draw it to this extreme rather than to that, for they are all perfectly similar; and if a person were to go round the world in a circle, he would often, when standing at the antipodes of his former position, speak of the same point as above and below; for, as I was saying just now, to speak of the whole which is in the form of a globe as having one part above and another below is not like a sensible man.

— Plato[6]

The term is taken up by Aristotle (De caelo 308a.20), Strabo, Plutarch and Diogenes Laertius, and was adopted into Latin as antipodes. The Latin word changed its sense from the original "under the feet, opposite side" to "those with the feet opposite", i.e. a bahuvrihi referring to hypothetical people living on the opposite side of the Earth. Medieval illustrations imagine them in some way "inverted", with their feet growing out of their heads, pointing upward.

In this sense, Antipodes first entered English in 1398 in a translation of the 13th century De Proprietatibus Rerum by Bartholomeus Anglicus, translated by John of Trevisa:

Yonde in Ethiopia ben the Antipodes, men that haue theyr fete ayenst our fete.

(In Modern English: Yonder in Ethiopia are the Antipodes, men that have their feet against our feet.)

Historical significance

Pomponius Mela, the first Roman geographer, asserted that the earth had two habitable zones, a North and South one, but that it would be impossible to get into contact with each other because of the unbearable heat at the equator.

The Terrestrial Sphere of Crates of Mallus (ca. 150 B.C.). Note the region of the antipodes in the southern half of the western hemisphere.

From the time of St Augustine, the Christian church was sceptical of the notion of the idea of the Antipodes. Augustine asserted that "it is too absurd to say that some men might have set sail from this side and, traversing the immense expanse of ocean, have propagated there a race of human beings descended from that one first man."[7]

In the Early Middle Ages, Isidore of Seville's widely read encyclopedia presented the term "antipodes" as referring to antichthones (people who lived on the opposite side of the Earth), as well as to a geographical place; these people came to play a role in medieval discussions about the shape of the Earth.[8] In 748, Pope Zachary declared belief "that beneath the earth there was another world and other men, another sun and moon", as apparently held by Vergilius of Salzburg, to be heretical.[9][10][11] The antipodes being an attribute of a spherical Earth, some authors used their perceived absurdity as an argument for a flat Earth. [citation needed] However, knowledge of the spherical Earth was widespread during the Middle Ages, only occasionally disputed on theological grounds. The medieval dispute surrounding the antipodes mainly concerned the question whether people could live on the opposite side of the earth: since the torrid clime was considered impassable, it would have been impossible to evangelize them. This posed the problem that Christ told the apostles to evangelize all mankind; with regard to the unreachable antipodes, this would have been impossible. Christ would either have appeared a second time, in the antipodes, or left them damned irredeemable. Such an argument was forwarded by the Spanish theologian Alonso Tostado as late as the 15th century and "St. Augustine doubts" was a response to Columbus's proposal to sail westwards to the Indies.[12]

The author of the Norwegian book Konungs Skuggsjá, from around 1250, discusses the existence of antipodes. He notes that (if they exist) they will see the sun in the north in the middle of the day and that they will have opposite seasons of the people living in the Northern Hemisphere.

The earliest surviving account by a European who had visited the Southern Hemisphere is that of Marco Polo (who, on his way home in 1292, sailed south of the Malay Peninsula). He noted that it was impossible to see the star Polaris from there.

The idea of dry land in the southern climes, the Terra Australis, was introduced by Ptolemy and appears on European maps as an imaginary continent from the 15th century. In spite of having been discovered relatively late by European explorers, Australia was inhabited very early in human history; the ancestors of the Indigenous Australians reached it at least 50,000 years ago.

List of antipodes

Earth

Some cities and towns which are near-antipodes in equirectangular projection. Blue labels pertain to cyan and brown labels pertain to yellow areas. Areas where cyan and yellow overlap (coloured green) are land antipodes.

Around 71% of the Earth's surface is covered by oceans, and seven-eighths of the Earth's land is confined to the land hemisphere, so the majority of locations on land do not have land-based antipodes.

The two largest human inhabited antipodal areas are located in East Asia (mainly eastern China) and South America (mainly northern Argentina and Chile). The Australian mainland is the largest landmass with its antipodes entirely in ocean, although some locations of mainland Australia and Tasmania are close to being antipodes of islands (Bermuda, Azores, Puerto Rico) in the North Atlantic Ocean. The largest landmass with antipodes entirely on land is the island of Borneo.

Cities

Exact or almost exact antipodes:

To within 100 km, with at least one major city (population of at least 1 million):

Taiwan (formerly called Formosa) is partly antipodal to the province of Formosa in Argentina.

Other major cities or capitals close to being antipodes:

Cities and geographic features

Gibraltar is approximately antipodal to Te Arai Beach about 85 km north of Auckland, New Zealand. This illustrates the old yet correct saying that the sun never sets on the British Empire; the sun still does not set on the British Commonwealth.

The northern part of New Caledonia, an overseas territory of France, is antipodal to some thinly populated desert in Mauritania, a part of the former French West Africa. Portions of Suriname, a former Dutch colony, are antipodal to Sulawesi, an Indonesian island spelled Celebes when it was part of the Netherlands East Indies. Luzon Island in the Philippines is antipodal to Eastern Bolivia. As with the British Empire, the sun set neither on the French Empire, the Dutch Empire, nor the Spanish Empire at their peaks.

Santa Vitória do Palmar, the most southerly town of more than 10,000 people in Brazil, is antipodal to Jeju Island, the southernmost territory of South Korea.

The Big Island of Hawaii is antipodal to the Okavango Delta in Botswana, with the island's largest city, Hilo, antipodal to Nxai Pan National Park.

Easter Island is antipodal to Desert National Park, 35 km from Jaisalmer, India.

Desolate Kerguelen Island is antipodal to an area of thinly inhabited plains on the border between the Canadian provinces of Alberta and Saskatchewan and the US state of Montana.

The Heard Island and McDonald Islands, an uninhabited Australian territory, is antipodal to an area in central Saskatchewan, including the towns of Leask and Shellbrook.

St. Paul Island and Amsterdam Island are antipodal to thinly populated parts of the eastern part of the US state of Colorado.

South Georgia Island is antipodal to the northernmost part of Sakhalin Island.

Lake Baikal is partially antipodal to the Straits of Magellan.

The Russian Antarctic research base Bellingshausen Station is antipodal to a land location in Russian Siberia.

Rottnest Island, off the coast of Western Australia, is approximately antipodal to Bermuda.

Flores Island, the westernmost island of the Azores, is nearly antipodal to Flinders Island between Tasmania and the Australian mainland.

By definition, the North Pole and the South Pole are antipodes.

As can be seen on the purple/blue map, the Pacific Ocean is so large that it stretches halfway around the world; parts of the Pacific off the coast of Peru are antipodal to parts of the same ocean off the coast of Southeast Asia.

Countries

The following countries are opposite more than one other country. (Antarctica is considered separately from any territorial claims.)

Countries No. of antipodal countries Antipodal countries
New Zealand 12 Mainland: Spain, Portugal, Morocco, UK (Gibraltar)
Chatham Islands: France
Kermadec Islands: Algeria
Niue: Niger
Tokelau: Nigeria
Cook Islands: Chad, (Penrhyn) Central African Republic, (Mangaia) Libya, (Pukapuka) Cameroon, (Nassau) Nigeria
France 12 Mainland: New Zealand (Chatham Islands)
Southern & Antarctic Lands: Canada, United States
French Guiana: Indonesia
New Caledonia: Mauritania, Western Sahara
Wallis and Futuna: Niger
French Polynesia: Sudan, Egypt, Saudi Arabia, Eritrea, Ethiopia
Brazil 9 China, Japan, South Korea, Philippines, Malaysia, Indonesia, Brunei, Palau, Federated States of Micronesia
Indonesia 8 Ecuador, Peru, Colombia, Venezuela, Brazil, Suriname, Guyana, France (French Guiana)
Peru 7 Vietnam, Cambodia, Laos, Thailand, Malaysia, Indonesia, China
United States 7 Mainland: France (Southern & Antarctic Lands)
Hawaii: Botswana, Namibia
Alaska: Antarctica
Palmyra Atoll & Kingman Reef: DR Congo
American Samoa: Niger, Nigeria
United Kingdom 7 (Falklands) China, Russia; (Gibraltar) New Zealand; (South Georgia and the South Sandwich Islands) Russia; (Pitcairn) Saudi Arabia, UAE (Bermuda) Australia
Niger 5 Samoa, Tonga, United States (American Samoa), France (Wallis and Futuna), New Zealand (Niue)
Antarctica 5 Greenland, Canada, United States, Russia, Norway
China 5 Mainland: Argentina, Chile, Uruguay, Bolivia, UK (Falkland Islands)
Malaysia 4 Ecuador, Peru, Brazil, Colombia
Argentina 4 China, Taiwan, Mongolia, Russia
Chile 4 China, Mongolia, Russia; Easter Island: India
Kiribati 4 Phoenix Islands (Orona): Nigeria; Line Islands: DR Congo, CAR, Sudan
Russia 4 Antarctica, Chile, Argentina, United Kingdom (Falklands etc.)
Australia 3 (Heard Island and McDonald Islands) Canada, (Christmas Island) Colombia, (Perth) Bermuda (UK)
Ecuador 3 Malaysia, Singapore, Indonesia
Philippines 3 Brazil, Bolivia, Paraguay
Vanuatu 3 Mauritania, Senegal, (Mere Lava) Mali
Paraguay 3 Taiwan, Japan, Philippines
Mali 3 Fiji, Vanuatu, Solomon Islands
Colombia 3 Indonesia, Malaysia, Australia (Christmas Island)
Nigeria 3 New Zealand (Tokelau, Cook Ils), United States (American Samoa), Kiribati
Canada 3 Antarctica, France (Kerguelen), Australia (Heard Island and McDonald Islands)
Taiwan 2 Paraguay, Argentina
Tonga 2 Algeria, Niger
Mongolia 2 Chile, Argentina
Tuvalu 2 Ghana, (Nanumanga, Nanumea) Ivory Coast
Fiji 2 Mali; (Rutuma) Burkina
Solomon Islands (Temoto) 2 Guinea, (Tikopia) Mali
Uruguay 2 China, South Korea
Bolivia 2 China, Philippines
Sudan 2 France (French Polynesia), Kiribati
Mauritania 2 France (New Caledonia), Vanuatu
Algeria 2 Tonga, New Zealand (Kermadec)
Central African Republic 2 Kiribati, New Zealand (Cook Ils)
Saudi Arabia 2 France (French Polynesia), UK (Pitcairn)
DR Congo 2 Kiribati, United States (Palmyra, Kingman Reef)
Japan 2 (Ryukyu) Brazil, Paraguay
South Korea 2 Uruguay, Brazil
Norway 2 (Svalbard) Antarctica, (Peter I Island) Russia

Countries matching up with just one other country are Morocco, Spain, Portugal (all with New Zealand); Chad, Libya, Cameroon (with the Cook Islands of New Zealand); Egypt, Eritrea, Ethiopia (with French Polynesia); Senegal (Vanuatu); UAE (Pitcairn); Ghana, Ivory Coast (Tuvalu); Burkina Faso (Rotuma in Fiji); Guinea (Solomon Islands); India (Easter Island); Laos, Cambodia, Vietnam, and Thailand (all with Peru); Singapore (Ecuador); Brunei, Palau, Micronesia (all with Brazil); Venezuela, Suriname (Indonesia).

Of these, the larger countries which are entirely antipodal to land are the Philippines, Malaysia, Taiwan, Fiji, Vanuatu, Brunei, and Samoa. Chile was as well prior to its expansion into the Atacama with the War of the Pacific.

Other bodies

Wikimedia Commons has media related to Antipodes maps.

See also

References

  1. ^ Antipodes, Liddell and Scott, "A Greek-English Lexicon", at Perseus.
  2. ^ Compact Oxford English Dictionary, 2008, "Antipodes" Access date: 2010-02-21.
  3. ^ J. W. Gregory (1912) The Making of the Earth, p 138
  4. ^ Simpson, J.J.; Taflove, Allen, "Two-dimensional FDTD model of antipodal ELF propagation and Schumann resonance of the Earth," Antennas and Wireless Propagation Letters, IEEE , vol.1, no.1, pp.53,56, 2002
  5. ^ Běhounková, M., G. Tobie, G. Choblet, and O. Čadek (2010), Coupling mantle convection and tidal dissipation: Applications to Enceladus and Earth-like planets, J. Geophys. Res., 115, E09011, doi:10.1029/2009JE003564.
  6. ^ Plato, Timaeus 63a, translated by Benjamin Jowett, (Indianapolis: Bobbs Merrill, 1949).[1]
  7. ^ De Civitate Dei, Book XVI, Chapter 9 — Whether We are to Believe in the Antipodes, translated by Rev. Marcus Dods, D.D.; from the Christian Classics Ethereal Library at Calvin College
  8. ^ Stevens, Wesley M. (1980), "The Figure of the Earth in Isidore's "De natura rerum"", Isis, 71 (2): 274, JSTOR 230175
  9. ^ Hasse, Wolfgang; Reinhold, Meyer, eds. (1993), The Classical Tradition and the Americas, Berlin: Walter de Gruyter, ISBN 3-11-011572-7 {{citation}}: Invalid |ref=harv (help)
  10. ^ Moretti, Gabriella (1993), The Other World and the 'Antipodes'. The Myth of Unknown Countries between Antiquity and the Renaissance, p. 265. In Hasse & Reinhold (1993, pp.241–84). {{citation}}: Invalid |ref=harv (help)CS1 maint: postscript (link)
  11. ^ Loughlin, James (1907), Antipodes in The Catholic Encyclopedia {{citation}}: Invalid |ref=harv (help)
  12. ^ Ferdinand Columbus (1543). The Life of the Admiral Chrispher Columbus (Translation by Benjamin Keen ed.). London, The Folio Society, 1960. p. 62.
  13. ^ If the earth were a sandwich, the show with zefrank
  14. ^ Mark Price, Antipodes: The Ingenious and Exhilarating Expedition of El Lider and La Campana, Longacre Press, Dunedin 2009 ISBN 978 1 877460 36 4
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