131-466: Stewart Island ( Māori : Rakiura , lit. ' glowing skies ', officially Stewart Island / Rakiura , formerly New Leinster ) is New Zealand 's third-largest island, located 30 kilometres (16 nautical miles) south of the South Island , across Foveaux Strait . It is a roughly triangular island with a total land area of 1,746 km (674 sq mi). Its 164-kilometre (102 mi) coastline
262-407: A by-election to fill the vacancy. The provinces have broken down because of their coming into conflict with the colonial government on many points, and especially on points of finance. Their doom was only a question of time, when it became obvious that they could not raise their own revenue; that they had to look to the general government to supply deficiencies; and that they could not borrow without
393-401: A geomagnetic storm temporarily enlarges the auroral oval. Large geomagnetic storms are most common during the peak of the 11-year sunspot cycle or during the three years after the peak. An electron spirals (gyrates) about a field line at an angle that is determined by its velocity vectors, parallel and perpendicular, respectively, to the local geomagnetic field vector B. This angle is known as
524-442: A licence was granted to Amphibian Airways to operate an air service between Invercargill and Stewart Island. In December 1950, finance was being sought for the purchase of a Grumman Widgeon amphibious aircraft . The inaugural flight to Half Moon Bay was made on 20 March 1951, with plans for a weekly service. In 1976, Stewart Island Air Services took over an amphibian air service to Stewart Island that had previously been operated by
655-432: A particle depends on the particle's pitch angle : the angle between its direction of motion and the local magnetic field. An aurora is created by processes that decrease the pitch angle of many individual electrons, freeing them from the magnetic trap and causing them to hit the atmosphere. In the case of diffuse auroras, the electron pitch angles are altered by their interaction with various plasma waves . Each interaction
786-753: A population density of 0.26 people per km. Stewart Island had a population of 408 at the 2018 New Zealand census , an increase of 30 people (7.9%) since the 2013 census , and an increase of 6 people (1.5%) since the 2006 census . There were 222 households, comprising 216 males and 195 females, giving a sex ratio of 1.11 males per female. The median age was 49.3 years (compared with 37.4 years nationally), with 54 people (13.2%) aged under 15 years, 57 (14.0%) aged 15 to 29, 204 (50.0%) aged 30 to 64, and 90 (22.1%) aged 65 or older. Ethnicities were 93.4% European/ Pākehā , 19.9% Māori , 1.5% Pasifika , 0.7% Asian , and 2.2% other ethnicities. People may identify with more than one ethnicity. The percentage of people born overseas
917-489: A possible strait. The strait was first charted by Owen Folger Smith , a New Yorker who had been in Sydney Harbour with Eber Bunker , from whom he probably learned of the eastern seal hunting . Smith charted the strait in the whaleboat of the sealing brig Union (out of New York) in 1804 and on his 1806 chart, it was called Smith's Straits. The island received its English name in honour of William W. Stewart . He
1048-493: A provincial council, and elected a superintendent who was not a member of the council. The councils elected their speaker at their first meeting after elections. The Act also created a national General Assembly consisting of the Legislative Council (appointed by the governor ) and the directly elected House of Representatives . These provinces came into effect on 17 January 1853 and the regulations defining
1179-713: A separate Crown Colony from New South Wales in May 1841. In 1846 the British Parliament passed the first New Zealand Constitution Act , which allowed for the establishment of provinces. Governor George Grey arrived in New Zealand in November 1845, and upon reading the new Constitution Act in May 1847 argued for its suspension in dispatches to the Colonial Office. Before this occurred, Grey proclaimed
1310-513: A southward component of the IMF, which can then directly connect to the high latitude geomagnetic field lines. The flow pattern of magnetospheric plasma is mainly from the magnetotail toward Earth, around Earth and back into the solar wind through the magnetopause on the day-side. In addition to moving perpendicular to Earth's magnetic field, some magnetospheric plasma travels down along Earth's magnetic field lines, gains additional energy and loses it to
1441-419: A surfer catching an ocean wave. This constantly-changing wave electric field can accelerate electrons along the field line, causing some of them to hit the atmosphere. Electrons accelerated by this mechanism tend to have a broad energy spectrum, in contrast to the sharply-peaked energy spectrum typical of electrons accelerated by quasi-static electric fields. Provinces of New Zealand The provinces of
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#17327732789491572-501: A velocity typically around 400 km/s, a density of around 5 ions/cm and a magnetic field intensity of around 2–5 nT (for comparison, Earth's surface field is typically 30,000–50,000 nT). During magnetic storms , in particular, flows can be several times faster; the interplanetary magnetic field (IMF) may also be much stronger. Joan Feynman deduced in the 1970s that the long-term averages of solar wind speed correlated with geomagnetic activity. Her work resulted from data collected by
1703-606: A weak glow (often deep red) observed around the two polar cusps, the field lines separating the ones that close through Earth from those that are swept into the tail and close remotely. Early work on the imaging of the auroras was done in 1949 by the University of Saskatchewan using the SCR-270 radar. The altitudes where auroral emissions occur were revealed by Carl Størmer and his colleagues, who used cameras to triangulate more than 12,000 auroras. They discovered that most of
1834-503: A year. Owing to an anomaly in the magnetic latitude contours, this location is well-placed for observing Aurora australis . Approximately 18,000 years ago during the Last Glacial Maximum when sea levels were over 100 metres lower than present day levels, Stewart Island and its surrounding islands were connected to the rest of New Zealand. Sea levels began to rise 7,000 years ago, eventually separating Stewart Island from
1965-535: A year. These factors combined can lead to minor cyclical changes in the detailed way that the IMF links to the magnetosphere. In turn, this affects the average probability of opening a door through which energy from the solar wind can reach Earth's inner magnetosphere and thereby enhance auroras. Recent evidence in 2021 has shown that individual separate substorms may in fact be correlated networked communities. Just as there are many types of aurora, there are many different mechanisms that accelerate auroral particles into
2096-468: Is about 85% of the area of Stewart Island / Rakiura. The area of the park excludes the township around Halfmoon Bay ( Oban ) and some roads as well as private or Māori-owned land further inland. Stewart Island covers 1,747.72 km (674.80 sq mi) including the offshore islands, the most sizeable being Ruapuke Island , Codfish Island / Whenua Hou and Taukihepa / Big South Cape Island . It had an estimated population of 460 as of June 2024, with
2227-563: Is composed of Anglem Complex diorites, minor gabbro and granite, and many pegmatites. The Freshwater Valley Fault in between is mainly alluvium and volcanic sediments. In January 2019, Stewart Island was accredited as a Dark Sky Sanctuary by the International Dark-Sky Association . This designation is given for sites in very remote locations to increase awareness of their dark sky characteristics and promote long-term conservation. The application for accreditation
2358-403: Is deeply indented by Paterson Inlet (east), Port Pegasus (south), and Mason Bay (west). The island is generally hilly (rising to 980 metres or 3,220 feet at Mount Anglem ) and densely forested. Flightless birds , including penguins, thrive because there are few introduced predators. Almost all the island is owned by the New Zealand government, and over 80 per cent of the island is set aside as
2489-443: Is essentially wave-particle scattering ; the electron energy after interacting with the wave is similar to its energy before interaction, but the direction of motion is altered. If the final direction of motion after scattering is close to the field line (specifically, if it falls within the loss cone ) then the electron will hit the atmosphere. Diffuse auroras are caused by the collective effect of many such scattered electrons hitting
2620-444: Is generally accompanied by decreasing peak emission heights of about 8 km for blue and green emissions and above average solar wind speeds ( c. 500 km/s ). In addition, the aurora and associated currents produce a strong radio emission around 150 kHz known as auroral kilometric radiation (AKR), discovered in 1972. Ionospheric absorption makes AKR only observable from space. X-ray emissions, originating from
2751-514: Is hilly and, like most of New Zealand, Stewart Island has an Oceanic climate . The north is dominated by the swampy valley of the Freshwater River . The river rises close to the northwestern coast and flows southeastwards into the large indentation of Paterson Inlet . The highest peak is Mount Anglem (980 metres (3,220 ft)), close to the northern coast. It is one of a rim of ridges that surround Freshwater Valley. The southern half
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#17327732789492882-520: Is induced within the conductor. The strength of the current depends on a) the rate of relative motion, b) the strength of the magnetic field, c) the number of conductors ganged together and d) the distance between the conductor and the magnetic field, while the direction of flow is dependent upon the direction of relative motion. Dynamos make use of this basic process ("the dynamo effect "), any and all conductors, solid or otherwise are so affected, including plasmas and other fluids. The IMF originates on
3013-484: Is more effectively transferred by the temporary magnetic connection between the field lines of the solar wind and those of the magnetosphere. Unsurprisingly this process is known as magnetic reconnection . As already mentioned, it happens most readily when the interplanetary field is directed southward, in a similar direction to the geomagnetic field in the inner regions of both the north magnetic pole and south magnetic pole . Auroras are more frequent and brighter during
3144-586: Is more uniformly undulating, rising to a ridge that runs south from the valley of the Rakeahua River , which also flows into Paterson Inlet. The southernmost point in this ridge is Mount Allen , at 750 metres (2,460 ft). Notable twin rock formations in this region are known as Gog and Magog. In the southeast the land is somewhat lower, and is drained by the valleys of the Toitoi River , Lords River , and Heron River . South West Cape on this island
3275-407: Is regularly derived from ground data and serves as a general measure of auroral activity. Kristian Birkeland deduced that the currents flowed in the east–west directions along the auroral arc, and such currents, flowing from the dayside toward (approximately) midnight were later named "auroral electrojets" (see also Birkeland currents ). Ionosphere can contribute to the formation of auroral arcs via
3406-451: Is similarly preserved. Stewart Island is the sole remaining breeding place of the critically endangered southern New Zealand dotterel . The South Island giant moa ( Dinornis robustus ) occurred on the island, subfossil remains having been retrieved in its dunes. As the island has always been sparsely populated and there has never been very much logging, much of the original wildlife is intact, including species that have been devastated on
3537-674: Is the southernmost point of the main islands of New Zealand. Mason Bay, on the west side, is notable as a long sandy beach on an island where beaches are typically far more rugged. One suggestion is that the bay was formed in the aftershock of a meteorite impact in the Tasman Sea ; however, no evidence has been found to support such a claim. Three large and many small islands lie around the coast. Notable among these are Ruapuke Island , in Foveaux Strait 32 kilometres (20 mi) northeast of Oban; Codfish Island / Whenua Hou , close to
3668-522: Is why there is a color differential with altitude; at high altitudes oxygen red dominates, then oxygen green and nitrogen blue/purple/red, then finally nitrogen blue/purple/red when collisions prevent oxygen from emitting anything. Green is the most common colour. Then comes pink, a mixture of light green and red, followed by pure red, then yellow (a mixture of red and green), and finally, pure blue. Precipitating protons generally produce optical emissions as incident hydrogen atoms after gaining electrons from
3799-524: The Arctic and Antarctic ). Auroras display dynamic patterns of brilliant lights that appear as curtains, rays, spirals, or dynamic flickers covering the entire sky. Auroras are the result of disturbances in the Earth's magnetosphere caused by the solar wind . Major disturbances result from enhancements in the speed of the solar wind from coronal holes and coronal mass ejections . These disturbances alter
3930-538: The Awarua took place on 10 March 1885, and a weekly service to Steward Island commenced. A government subsidy was required to support the service, but it brought economic benefit by supporting the development of the fishing industry based on Stewart Island and increased the number of visitors. Many different vessels were used by the Bluff Harbour Board on the Foveaux Strait ferry service in the first half of
4061-536: The Colony of New Zealand existed as a form of sub-national government . Initially established in 1846 when New Zealand was a Crown colony without responsible government , two provinces ( New Ulster and New Munster ) were first created. Each province had its own legislative council and governor. With the passing of the New Zealand Constitution Act 1852 the provinces were recreated around
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4192-481: The Explorer 33 spacecraft. The solar wind and magnetosphere consist of plasma (ionized gas), which conducts electricity. It is well known (since Michael Faraday 's work around 1830) that when an electrical conductor is placed within a magnetic field while relative motion occurs in a direction that the conductor cuts across (or is cut by ), rather than along , the lines of the magnetic field, an electric current
4323-612: The Mount Cook Group . In 1980, Stewart Island Air Services rebranded as Southern Air. By 1980, a sealed airstrip had been built at Ryan's Creek above Oban, and services from Invercargill were provided using Nomad and Britten-Norman Islander aircraft. Southern Air rebranded to Stewart Island Flights in 2020. In 1998 a Southern Air Cessna ditched into Foveaux Strait on a trip from Stewart Island to Invercargill after losing power to both engines, resulting in five deaths. Oban has mainly sealed main roads, and some gravel roads on
4454-626: The Rakiura National Park . Stewart Island's economy depends on fishing and summer tourism . Its permanent population was recorded at 408 people in the 2018 census , most of whom live in the settlement of Oban on the eastern side of the island. Ferries connect the settlement to Bluff in the South Island. Stewart Island is part of the Southland District for local government purposes. Archaeology indicates that
4585-613: The Shetland Islands settled in the early 1870s. This was unsuccessful, and the settlers left within one to two years, most for sawmilling villages elsewhere on the island. Geologically, Stewart Island is made up of rocks from the Median Batholith. The island is mostly composed of granite, particularly the southern two thirds of the island. The northern third (north of the Freshwater Valley Fault)
4716-467: The feedback instability under high ionospheric resistance conditions, observed at night time and in dark Winter hemisphere. Earth is constantly immersed in the solar wind , a flow of magnetized hot plasma (a gas of free electrons and positive ions) emitted by the Sun in all directions, a result of the two-million-degree temperature of the Sun's outermost layer, the corona . The solar wind reaches Earth with
4847-411: The mesosphere in presence of electron precipitation . Horse-collar auroras (HCA) are auroral features in which the auroral ellipse shifts poleward during the dawn and dusk portions and the polar cap becomes teardrop-shaped. They form during periods when the interplanetary magnetic field (IMF) is permanently northward, when the IMF clock angle is small. Their formation is associated with the closure of
4978-455: The "pitch angle" of the particle. The distance, or radius, of the electron from the field line at any time is known as its Larmor radius. The pitch angle increases as the electron travels to a region of greater field strength nearer to the atmosphere. Thus, it is possible for some particles to return, or mirror, if the angle becomes 90° before entering the atmosphere to collide with the denser molecules there. Other particles that do not mirror enter
5109-512: The 1880s (e.g. Otago) or 2006 (Tasman). Some of the names persist in other contexts as well, such as health administration districts: Northland , Waitemata , Auckland †, Counties Manukau , Waikato , Bay of Plenty , Lakes (Rotorua/Taupo) , Hawke's Bay †, MidCentral (Manawatu) , Tairawhiti (Gisborne) , Taranaki , Whanganui , Wairarapa , Hutt Valley , Capital and Coast (Wellington) †, Nelson (Marlborough) †, West Coast †, Canterbury †, South Canterbury and Southern (Otago) †. Some of
5240-409: The 1960s by many research teams using rockets and satellites to traverse the auroral zone. The main findings have been that auroral arcs and other bright forms are due to electrons that have been accelerated during the final few 10,000 km or so of their plunge into the atmosphere. These electrons often, but not always, exhibit a peak in their energy distribution, and are preferentially aligned along
5371-463: The 20th century, including the Southland and Theresa Ward , MV. Tamatea , and the steamer Orewa . Demands for a daily service across Foveaux were published in 1937. The twin screw steamer Wairua took over the Foveaux Strait ferry service in 1944. By 1959, the ferry service was operating with annual losses of £7,464. The steamer Wairua was 46 years old by that time, and a new replacement vessel
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5502-590: The Abolition of Provinces Act 1875, during the Premiership of Harry Atkinson . For the purposes of the Act, the provinces formally ceased to exist on 1 January 1877. Upon the abolition of the provinces, they took the legal status of provincial districts, which had no administrative functions. Local government was vested in elected borough and county councils. The Counties Bill of 1876 created 63 counties out of
5633-670: The General Assembly passed the New Provinces Act 1858. This Act allowed any district of between 500 thousand and 3 million acres (2,000–12,000 km ) of land with a European population of no fewer than 1,000 people to petition for separation provided that at least 60% of electors agreed. As a result, Hawke's Bay Province separated from Wellington on 1 November 1858; Marlborough Province from Nelson on 1 November 1859; and Southland Province from Otago on 1 April 1861. New Plymouth also changed its name to Taranaki under
5764-515: The Roman goddess of the dawn, Aurora , who travelled from east to west announcing the coming of the Sun . Ancient Greek poets used the corresponding name " Eos " metaphorically to refer to dawn, often mentioning its play of colours across the otherwise dark sky (e.g., "rosy-fingered dawn"). The words borealis and australis are derived from the names of the ancient gods of the north wind ( Boreas ) and
5895-524: The Sun, linked to the sunspots , and its field lines (lines of force) are dragged out by the solar wind. That alone would tend to line them up in the Sun-Earth direction, but the rotation of the Sun angles them at Earth by about 45 degrees forming a spiral in the ecliptic plane, known as the Parker spiral . The field lines passing Earth are therefore usually linked to those near the western edge ("limb") of
6026-588: The amount of acceleration imparted to the precipitating particles. Most of the planets in the Solar System , some natural satellites , brown dwarfs , and even comets also host auroras. The term aurora borealis was coined by Galileo in 1619, from the Roman Aurora, goddess of the dawn , and the Greek Boreas, god of the cold north wind . The word aurora is derived from the name of
6157-461: The analogue switch off on 28 April 2013. Oban has ADSL broadband and phone services delivering speeds up to 24 Mbit/s download. Aurora An aurora ( pl. aurorae or auroras ), also commonly known as the northern lights ( aurora borealis ) or southern lights ( aurora australis ), is a natural light display in Earth 's sky, predominantly seen in high-latitude regions (around
6288-486: The atmosphere and contribute to the auroral display over a range of altitudes. Other types of auroras have been observed from space; for example, "poleward arcs" stretching sunward across the polar cap, the related "theta aurora", and "dayside arcs" near noon. These are relatively infrequent and poorly understood. Other interesting effects occur such as pulsating aurora, "black aurora" and their rarer companion "anti-black aurora" and subvisual red arcs. In addition to all these,
6419-423: The atmosphere in the auroral zones. The cusps of the magnetosphere, separating geomagnetic field lines that close through Earth from those that close remotely allow a small amount of solar wind to directly reach the top of the atmosphere, producing an auroral glow. On 26 February 2008, THEMIS probes were able to determine, for the first time, the triggering event for the onset of magnetospheric substorms . Two of
6550-456: The atmosphere. Electron aurora in Earth's auroral zone (i.e. commonly visible aurora) can be split into two main categories with different immediate causes: diffuse and discrete aurora. Diffuse aurora appear relatively structureless to an observer on the ground, with indistinct edges and amorphous forms. Discrete aurora are structured into distinct features with well-defined edges such as arcs, rays and coronas; they also tend to be much brighter than
6681-447: The atmosphere. Proton auroras are usually observed at lower latitudes. Bright auroras are generally associated with Birkeland currents (Schield et al., 1969; Zmuda and Armstrong, 1973 ), which flow down into the ionosphere on one side of the pole and out on the other. In between, some of the current connects directly through the ionospheric E layer (125 km); the rest ("region 2") detours, leaving again through field lines closer to
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#17327732789496812-439: The atmosphere. The process is mediated by the plasma waves, which become stronger during periods of high geomagnetic activity , leading to increased diffuse aurora at those times. In the case of discrete auroras, the trapped electrons are accelerated toward Earth by electric fields that form at an altitude of about 4000–12000 km in the "auroral acceleration region". The electric fields point away from Earth (i.e. upward) along
6943-732: The aurora borealis and changes simultaneously with changes in the northern auroral zone. The aurora australis is visible from high southern latitudes in Antarctica , the Southern Cone , South Africa , Australasia and under exceptional circumstances as far north as Uruguay . The aurora borealis is visible from areas around the Arctic such as Alaska , Canada , Iceland , Greenland , the Faroe Islands , Scandinavia , Finland , Scotland , and Russia . A geomagnetic storm causes
7074-518: The auroral oval to active displays along the darkside and after 1–3 hours they gradually change back. Changes in auroras over time are commonly visualized using keograms . At shorter time scales, auroras can change their appearances and intensity, sometimes so slowly as to be difficult to notice, and at other times rapidly down to the sub-second scale. The phenomenon of pulsating auroras is an example of intensity variations over short timescales, typically with periods of 2–20 seconds. This type of aurora
7205-726: The auroral ovals (north and south) to expand, bringing the aurora to lower latitudes. On rare occasions, the aurora borealis can be seen as far south as the Mediterranean and the southern states of the US while the aurora australis can be seen as far north as New Caledonia and the Pilbara region in Western Australia . During the Carrington Event , the greatest geomagnetic storm ever observed, auroras were seen even in
7336-412: The background magnetic field (comparable to the electron inertial length or ion gyroradius ), Alfvén waves develop a significant electric field parallel to the background magnetic field. This electric field can accelerate electrons to keV energies, significant to produce auroral arcs. If the electrons have a speed close to that of the wave's phase velocity, they are accelerated in a manner analogous to
7467-418: The boundaries of the provinces were gazetted on 28 February. Electoral regulations were gazetted on 5 March. As with general elections, elections were open to males 21 years or older who owned freehold property worth £50 a year. The first provincial elections were held at the same time as the 1853 general elections . While Governor George Grey had issued the writs for the provincial and general elections at
7598-447: The chief executive of Real Journeys stated: "Not only are Stewart Island ferries completely unsubsidised but the Foveaux Strait is an extremely expensive piece of water to operate on commercially". Stewart Island Flights provides air services across Foveaux Strait between Invercargill Airport and Ryan's Creek Aerodrome on Stewart Island. Their aircraft also land on the sand at Mason Bay, Doughboy Bay, and West Ruggedy Beach. In 1950,
7729-465: The collision of particles precipitated into the atmosphere. Both incoming electrons and protons may be involved. Excitation energy is lost within the atmosphere by the emission of a photon, or by collision with another atom or molecule: Oxygen is unusual in terms of its return to ground state: it can take 0.7 seconds to emit the 557.7 nm green light and up to two minutes for the red 630.0 nm emission. Collisions with other atoms or molecules absorb
7860-507: The colony becoming liable. Almost as soon as they were founded, New Zealand's provinces were the subject of protracted political debate. Two factions emerged in the General Assembly : "Centralists", favouring a strong central government and "Provincialists", favouring strong regional governments. The Centralist members of the General Assembly regarded the provinces as inherently self-interested, and prone to pork-barrel politics. In
7991-478: The company Stewart Island Marine, and launched in April 1999. The new vessel was a catamaran capable of taking 100 passengers, one third more than the vessel it replaced. In 2004, after operating the business for 14 years, Stewart Island Marine sold the ferry service to Stewart Island Experience — a joint venture between two private individuals and the tourism company Real Journeys . A third vessel seating 160 passengers
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#17327732789498122-591: The construction of railways, for example, three of the provinces had constructed railways (as was the case in Australia) to different track gauges , with Canterbury Provincial Railways being built to "broad" gauge, Southland's railways being built to "standard" gauge. As a result, the Public Works Act of 1870 standardised the gauge to be used, and Otago's first railway, the Port Chalmers railway ,
8253-601: The counties were replaced by enlarged district councils . The Department of Lands and Survey split the country into the Land Districts of Auckland (North), Auckland (South), Hawkes Bay, Gisborne, Taranaki, Wellington, Canterbury, Marlborough, Nelson, Westland, Otago and Southland. The New Zealand Rugby Union was formed in 1892 with foundation members principally being provinces: Auckland †, Hawke's Bay †, Taranaki †, Manawatu , Wanganui , Wairarapa , Wellington †, Nelson †, Marlborough † and South Canterbury . At
8384-468: The currents are the direct result of electron acceleration into the atmosphere by wave/particle interactions. Ionospheric resistance has a complex nature, and leads to a secondary Hall current flow. By a strange twist of physics, the magnetic disturbance on the ground due to the main current almost cancels out, so most of the observed effect of auroras is due to a secondary current, the auroral electrojet . An auroral electrojet index (measured in nanotesla)
8515-416: The diffuse aurora. In both cases, the electrons that eventually cause the aurora start out as electrons trapped by the magnetic field in Earth's magnetosphere . These trapped particles bounce back and forth along magnetic field lines and are prevented from hitting the atmosphere by the magnetic mirror formed by the increasing magnetic field strength closer to Earth. The magnetic mirror's ability to trap
8646-404: The dune aurora phenomenon was discovered by Finnish citizen scientists . It consists of regularly-spaced, parallel stripes of brighter emission in the green diffuse aurora which give the impression of sand dunes. The phenomenon is believed to be caused by the modulation of atomic oxygen density by a large-scale atmospheric wave travelling horizontally in a waveguide through an inversion layer in
8777-424: The early 1930s and with a checklist by botanist Leonard Cockayne populated it with all the local indigenous plants. She gave the land and her house to the government in 1940, and today Moturau Moana is New Zealand's southernmost public garden. There are many species of birds on Stewart Island that have been able to continue to thrive because of the absence of the stoats, ferrets, and weasels that humans brought to
8908-458: The electric field increases the kinetic energy of all of the electrons transiting downward through the acceleration region by the same amount. This accelerates electrons starting from the magnetosphere with initially low energies (tens of eV or less) to energies required to create an aurora (100s of eV or greater), allowing that large source of particles to contribute to creating auroral light. The accelerated electrons carry an electric current along
9039-454: The equator and closing through the "partial ring current" carried by magnetically trapped plasma. The ionosphere is an ohmic conductor , so some consider that such currents require a driving voltage, which an, as yet unspecified, dynamo mechanism can supply. Electric field probes in orbit above the polar cap suggest voltages of the order of 40,000 volts, rising up to more than 200,000 volts during intense magnetic storms. In another interpretation,
9170-490: The excitation energy and prevent emission; this process is called collisional quenching . Because the highest parts of the atmosphere contain a higher percentage of oxygen and lower particle densities, such collisions are rare enough to allow time for oxygen to emit red light. Collisions become more frequent progressing down into the atmosphere due to increasing density, so that red emissions do not have time to happen, and eventually, even green light emissions are prevented. This
9301-596: The ferry service is operated by the tourism company RealNZ (formerly Real Journeys). The first scheduled service across Foveaux Strait began in 1877 for weekly mail delivery, but soon also carried passengers and general cargo. A larger vessel, the Bluff Harbour Board tug P.S. Awarua , took over the service in 1885. The Awarua arrived in Bluff on 4 January 1885, after a delivery voyage lasting more than 6 months since leaving dock in London. A trial excursion to Stewart Island on
9432-465: The five probes, positioned approximately one third the distance to the Moon, measured events suggesting a magnetic reconnection event 96 seconds prior to auroral intensification. Geomagnetic storms that ignite auroras may occur more often during the months around the equinoxes . It is not well understood, but geomagnetic storms may vary with Earth's seasons. Two factors to consider are the tilt of both
9563-483: The great fish Te Ika a Māui , the North Island . Rakiura is the commonly known Māori name. It is usually translated as "Glowing Skies", a reference to the aurora australis , the southern lights that are a phenomenon of southern latitudes. For some, Rakiura is the abbreviated version of Te Rakiura a Te Rakitamau, translated as "great blush of Rakitamau", in reference to the latter's embarrassment when refused
9694-443: The hand in marriage of not one but two daughters of an island chief. According to Māori legend, a chief on the island named Te Rakitamau was married to a young woman who became terminally ill and implored him to marry her cousin after she died. Te Rakitamau paddled across Te Moana Tapokopoko a Tawhiki ( Foveaux Strait ) to the South Island where the cousin lived, only to discover she had recently married. He blushed with embarrassment; so
9825-626: The inland areas. Almost all the island is owned by the New Zealand government and over 80 per cent of the island is set aside as the Rakiura National Park , New Zealand's newest national park. Many of the small offshore islands, including the Snares, are also protected. The ferry journey across Foveaux Strait between Bluff Harbour on the South Island and Oban in Stewart Island is about 39 km (21 nmi) long. The present high speed catamaran service typically takes one hour. As of 2024,
9956-430: The intense phase of the solar cycle when coronal mass ejections increase the intensity of the solar wind. Earth's magnetosphere is shaped by the impact of the solar wind on Earth's magnetic field. This forms an obstacle to the flow, diverting it, at an average distance of about 70,000 km (11 Earth radii or Re), producing a bow shock 12,000 km to 15,000 km (1.9 to 2.4 Re) further upstream. The width of
10087-401: The interaction of the solar wind with Earth's magnetosphere . The varying intensity of the solar wind produces effects of different magnitudes but includes one or more of the following physical scenarios. The details of these phenomena are not fully understood. However, it is clear that the prime source of auroral particles is the solar wind feeding the magnetosphere, the reservoir containing
10218-466: The island was called Te Ura o Te Rakitamau. Margaret Cameron-Ash claims that James Cook established the insularity of Stewart Island during his first Pacific voyage in 1770 but decided to hide his discovery for reasons of military and colonial policy. However, G. A. Mawer argues that Cook was simply unsure whether it was an island because his focus was on finding the southern extent of New Zealand, and conditions were unfavourable for more closely exploring
10349-484: The island was established as one of the three Provinces of New Zealand and was named New Leinster . However, the province existed on paper only and was abolished after only five years. With the passing of the New Zealand Constitution Act 1846 , the island became part of New Munster , which entirely included the South Island. When New Munster was abolished in 1853, Stewart Island became part of Otago Province until 1861, when Southland Province split from Otago. In 1876,
10480-533: The island was settled in the 14th century, shortly after the Māori settled in the South Island . The original Māori name, Te Punga o Te Waka a Māui , positions the island firmly at the heart of Māori mythology. Translated as "The Anchor Stone of Māui’s Canoe", it refers to the part played by the island in the legend of Māui and his crew, who from their canoe Te Waka a Māui (the South Island), caught and raised
10611-452: The large colonies of sooty shearwaters on the offshore Muttonbird Islands are subject to muttonbirding , a sustainable harvesting programme managed by Rakiura Māori. Meanwhile, a small population of kākāpō , a flightless parrot which is very close to extinction, was found on Stewart Island in 1977 and the birds subsequently moved to smaller islands such as Codfish Island / Whenua Hou for protection from feral cats. The South Island saddleback
10742-509: The light is produced between 90 and 150 km (56 and 93 mi) above the ground, while extending at times to more than 1,000 km (620 mi). According to Clark (2007), there are five main forms that can be seen from the ground, from least to most visible: Brekke (1994) also described some auroras as "curtains". The similarity to curtains is often enhanced by folds within the arcs. Arcs can fragment or break up into separate, at times rapidly changing, often rayed features that may fill
10873-762: The local direction of the magnetic field. Electrons mainly responsible for diffuse and pulsating auroras have, in contrast, a smoothly falling energy distribution, and an angular (pitch-angle) distribution favouring directions perpendicular to the local magnetic field. Pulsations were discovered to originate at or close to the equatorial crossing point of auroral zone magnetic field lines. Protons are also associated with auroras, both discrete and diffuse. Auroras result from emissions of photons in Earth's upper atmosphere , above 80 km (50 mi), from ionized nitrogen atoms regaining an electron, and oxygen atoms and nitrogen based molecules returning from an excited state to ground state . They are ionized or excited by
11004-417: The lowland areas with mānuka shrubland at higher elevations. The trees are thought to have become established here since the last ice age from seeds brought across the strait by seabirds, which would explain why the beech trees that are so common in New Zealand, but whose seeds are dispersed by the wind rather than birds, are not found on Stewart Island. Noeline Baker purchased land near Halfmoon Bay in
11135-426: The magnetic field line. Electrons moving downward through these fields gain a substantial amount of energy (on the order of a few keV ) in the direction along the magnetic field line toward Earth. This field-aligned acceleration decreases the pitch angle for all of the electrons passing through the region, causing many of them to hit the upper atmosphere. In contrast to the scattering process leading to diffuse auroras,
11266-432: The magnetic field lines (a Birkeland current ). Since the electric field points in the same direction as the current, there is a net conversion of electromagnetic energy into particle energy in the auroral acceleration region (an electric load ). The energy to power this load is eventually supplied by the magnetized solar wind flowing around the obstacle of Earth's magnetic field, although exactly how that power flows through
11397-422: The magnetic flux at the top of the dayside magnetosphere by the double lobe reconnection (DLR). There are approximately 8 HCA events per month, with no seasonal dependence, and that the IMF must be within 30 degrees of northwards. Conjugate auroras are nearly exact mirror-image auroras found at conjugate points in the northern and southern hemispheres on the same geomagnetic field lines. These generally happen at
11528-413: The magnetosphere abreast of Earth is typically 190,000 km (30 Re), and on the night side a long "magnetotail" of stretched field lines extends to great distances (> 200 Re). The high latitude magnetosphere is filled with plasma as the solar wind passes Earth. The flow of plasma into the magnetosphere increases with additional turbulence, density, and speed in the solar wind. This flow is favoured by
11659-490: The magnetosphere is still an active area of research. While the energy to power the aurora is ultimately derived from the solar wind, the electrons themselves do not travel directly from the solar wind into Earth's auroral zone; magnetic field lines from these regions do not connect to the solar wind, so there is no direct access for solar wind electrons. Some auroral features are also created by electrons accelerated by dispersive Alfvén waves . At small wavelengths transverse to
11790-414: The main islands. There are even more species of birds, including huge colonies of sooty shearwater and other seabirds, on The Snares and the other smaller islands offshore. The birds of Stewart Island include weka , kākā , albatross , the flightless Stewart Island kiwi , silvereyes , fantails , and kererū . The endangered yellow-eyed penguin has a significant number of breeding sites here, while
11921-442: The mainland post-colonisation. However, although habitats and wildlife were not threatened by invasive species historically, now there are populations of brushtail possums , feral cats, hedgehogs and three species of rats, but no mustelids or mice. There is a large population of white-tailed deer , which were introduced to coastal areas and are hunted for meat and sport. There is also a small population of red deer , confined to
12052-425: The mainland. The only town is Oban , on Halfmoon Bay . A previous settlement, Port Pegasus , once boasted several stores and a post office, and was located on the southern coast of the island. It is now uninhabited, and is accessible only by boat or by an arduous hike through the island. Another site of former settlement is at Port William , a four-hour walk around the north coast from Oban, where immigrants from
12183-857: The names of former provinces and current regions have a tendency to be preceded by "the". Thus, for example, we have Auckland , Canterbury , Hawke's Bay , Marlborough and Wellington , but the Waikato , the Manawatu , the Bay of Plenty , and the West Coast . The current regions of New Zealand and most of their councils came about in 1989: Northland , Auckland †, Waikato , Bay of Plenty , Gisborne , Hawke's Bay †, Taranaki †, Manawatu-Whanganui , Wellington †, Tasman , Nelson †, Marlborough †, West Coast †, Canterbury †, Otago † and Southland †. Another usage of words associated with
12314-433: The noon direction and 23° away in the midnight direction. The peak equatorward extent of the oval is displaced slightly from geographic midnight. It is centered about 3–5° nightward of the magnetic pole, so that auroral arcs reach furthest toward the equator when the magnetic pole in question is in between the observer and the Sun , which is called magnetic midnight . Early evidence for a geomagnetic connection comes from
12445-430: The northwest shore; and Big South Cape Island , off the southwestern tip. The Tītī / Muttonbird Islands group is between Stewart Island and Ruapuke Island, around Big South Cape Island, and off the southeastern coast. Other islands of interest include Bench Island, Native Island, and Ulva Island , all close to the mouth of Paterson Inlet , and Pearl Island, Anchorage Island , and Noble Island, close to Port Pegasus in
12576-780: The old provinces. The former boundaries of the provinces served as administrative areas for the education boards set up under the Education Act of 1877 and for the offices of several Government Departments, including the Department of Lands and Survey . Upon abolition, various responsibilities were delegated to boards. For example, the Education Act 1877 created the Education Boards for Auckland, Hamilton, Hawkes Bay, Taranaki, Wanganui, Wellington, Nelson, Westland, Southland, Canterbury and Otago districts. In 1989
12707-510: The opposite order. Until about 1963, it was thought that these changes are due to the rotation of the Earth under a pattern fixed with respect to the Sun. Later, it was found by comparing all-sky films of auroras from different places (collected during the International Geophysical Year ) that they often undergo global changes in a process called auroral substorm . They change in a few minutes from quiet arcs all along
12838-532: The outskirts. The only ferry/barge link to the South Island for vehicles is to Bluff. Stewart Island is able to receive most AM and FM radio stations broadcast in the Southland region. Television services are available via satellite using Sky or Freeview . Analogue terrestrial television services could be received on Stewart Island from the Hedgehope television transmitter located in the South Island prior to
12969-456: The particles associated with auroras, have also been detected. Aurora noise , similar to a crackling noise, begins about 70 m (230 ft) above Earth's surface and is caused by charged particles in an inversion layer of the atmosphere formed during a cold night. The charged particles discharge when particles from the Sun hit the inversion layer, creating the noise. In 2016, more than fifty citizen science observations described what
13100-610: The present day regions , for example, the Manawatū-Whanganui region is largely in the Wellington provincial district. The districts are represented by teams in rugby union 's ITM Cup and Heartland Championship , both of which replaced the National Provincial Championship in 2006, although the term "provincial" is still used in connection with rugby for the present 29 unions whether founded in
13231-571: The provinces became known as provincial districts . Their principal legacy is the use of some provincial boundaries to determine the geographical boundaries for anniversary day public holidays . Following the Treaty of Waitangi in 1840, New Zealand became a British colony, initially as part of New South Wales . The Royal Charter of November 1840 stated that the islands of New Zealand were "designated and known respectively" as: These names were of geographic significance only. New Zealand became
13362-633: The provinces were abolished altogether. For most of the twentieth century, "Stewart Island" was the official name, and the most commonly used. The name was officially altered to Stewart Island/Rakiura by the Ngāi Tahu Claims Settlement Act 1998 , one of many such changes under the Ngāi Tahu treaty settlement. Rabbits were introduced to the island in 1943 which later became a pest after rapid multiplication. Stewart Island has an area of 1,680 square kilometres (650 sq mi). Its terrain
13493-439: The provinces were separated from the central government for the first time. New Ulster and New Munster had their own seals. New provinces were formed by the New Zealand Constitution Act 1852 . This Act established a quasi-federal system of government and divided the country into the six provinces of Auckland , New Plymouth , Wellington , Nelson , Canterbury , and Otago . Each province elected its own legislature known as
13624-576: The provincial boundaries on 10 March 1848: Each province had a Lieutenant-Governor , appointed by the Governor-in-Chief. The 1846 Constitution Act was suspended in early 1848, with the only operative provisions relating to the reform of the provinces. News of the suspension did not reach New Zealand until 23 March 1848, when the immigrant ship John Wickliffe arrived in Port Chalmers to begin European settlement of Otago. In addition,
13755-593: The radiation zones and temporarily magnetically trapped particles confined by the geomagnetic field, coupled with particle acceleration processes. The immediate cause of the ionization and excitation of atmospheric constituents leading to auroral emissions was discovered in 1960, when a pioneering rocket flight from Fort Churchill in Canada revealed a flux of electrons entering the atmosphere from above. Since then an extensive collection of measurements has been acquired painstakingly and with steadily improving resolution since
13886-431: The ribbon). The processes that cause STEVE are also associated with a picket-fence aurora, although the latter can be seen without STEVE. It is an aurora because it is caused by precipitation of electrons in the atmosphere but it appears outside the auroral oval, closer to the equator than typical auroras. When the picket-fence aurora appears with STEVE, it is below. First reported in 2020, and confirmed in 2021,
14017-606: The rules governing commercial activities. For example, every transport service operated solely on Great Barrier Island , the Chatham Islands , or Stewart Island is exempt from the Transport Act of 1962. Although the clay soil is not very fertile, the high rainfall and warm weather mean that the island is densely forested throughout. Native plants include the world's southernmost dense forest of podocarps (southern conifers) and hardwoods such as rātā and kāmahi in
14148-433: The same Act. Stewart Island / Rakiura, which had since 1853 not been part of any province, was annexed to the province of Southland on 10 November 1863. Provinces established under this act elected their superintendents in a different way. Members of the provincial council would elect a suitable person listed on the electoral roll as superintendent by a majority. If such a person was an elected member, this would result in
14279-405: The same time, the provincial councils met before the general assembly met, in May 1854. The New Zealand Constitution Amendment Act 1857 provided for the appointment of a deputy superintendent. The Constitution Act provided for the creation of additional provinces, and when the spread of European settlements between the original centres of the provincial governments and the outlying settlers grew,
14410-513: The service would be withdrawn. Private operators would be invited to operate a service. The Wairua continued on the Stewart Island ferry service until September 1985, when she was sold for service in Fiji. Private operators provided a replacement ferry service to Stewart Island after the government service ended in 1985. A new ferry for the Stewart Island service was built in Invercargill for
14541-509: The six planned settlements or "colonies". By 1873 the number of provinces had increased to nine, but they had become less isolated from each other and demands for centralised government arose. In 1875 the New Zealand Parliament decided to abolish the provincial governments, and they came to an end in November 1876. They were superseded by counties , which were later replaced by territorial authorities . Following abolition,
14672-416: The solar and Earth's axis to the ecliptic plane. As Earth orbits throughout a year, it experiences an interplanetary magnetic field (IMF) from different latitudes of the Sun, which is tilted at 8 degrees. Similarly, the 23-degree tilt of Earth's axis about which the geomagnetic pole rotates with a diurnal variation changes the daily average angle that the geomagnetic field presents to the incident IMF throughout
14803-460: The south wind ( Auster ) in Greco-Roman mythology . Auroras are most commonly observed in the "auroral zone", a band approximately 6° (~660 km) wide in latitude centered on 67° north and south. The region that currently displays an aurora is called the "auroral oval". The oval is displaced by the solar wind, pushing it about 15° away from the geomagnetic pole (not the geographic pole) in
14934-474: The southwest. Further offshore The Snares are oceanic islands, a volcano and some smaller islets, that were never connected to the larger Stewart Island. Stewart Island has a temperate climate. However, one travel guide mentions "frequent downpours that make 'boots and waterproof clothing mandatory", and another guide says that rainfall in Oban, the principal settlement, is 1,600 to 1,800 mm (63 to 71 in)
15065-402: The statistics of auroral observations. Elias Loomis (1860), and later Hermann Fritz (1881) and Sophus Tromholt (1881) in more detail, established that the aurora appeared mainly in the auroral zone. In northern latitudes , the effect is known as the aurora borealis or the northern lights. The southern counterpart, the aurora australis or the southern lights, has features almost identical to
15196-409: The time of the equinoxes , when there is little difference in the orientation of the north and south geomagnetic poles to the sun. Attempts were made to image conjugate auroras by aircraft from Alaska and New Zealand in 1967, 1968, 1970, and 1971, with some success. A full understanding of the physical processes which lead to different types of auroras is still incomplete, but the basic cause involves
15327-544: The time, three major South Island Provincial Unions – Canterbury †, Otago † and Southland † – resisted the central authority of the NZRU. Some current Provincial Anniversary Days are still public holidays in New Zealand : Auckland†, Taranaki†, Hawkes' Bay†, Wellington†, Marlborough†, Nelson†, Canterbury†, Canterbury (South), Westland†, Otago†, Southland† and Chatham Islands. † indicates it reflects an original province. The provincial districts had different boundaries from
15458-402: The trajectories of charged particles in the magnetospheric plasma . These particles, mainly electrons and protons , precipitate into the upper atmosphere ( thermosphere / exosphere ). The resulting ionization and excitation of atmospheric constituents emit light of varying colour and complexity. The form of the aurora, occurring within bands around both polar regions, is also dependent on
15589-414: The tropics. Auroras seen within the auroral oval may be directly overhead. From farther away, they illuminate the poleward horizon as a greenish glow, or sometimes a faint red, as if the Sun were rising from an unusual direction. Auroras also occur poleward of the auroral zone as either diffuse patches or arcs, which can be subvisual. Auroras are occasionally seen in latitudes below the auroral zone, when
15720-406: The visible Sun at any time. The solar wind and the magnetosphere, being two electrically conducting fluids in relative motion, should be able in principle to generate electric currents by dynamo action and impart energy from the flow of the solar wind. However, this process is hampered by the fact that plasmas conduct readily along magnetic field lines, but less readily perpendicular to them. Energy
15851-506: The whole sky. These are also known as discrete auroras , which are at times bright enough to read a newspaper by at night. These forms are consistent with auroras being shaped by Earth's magnetic field. The appearances of arcs, rays, curtains, and coronas are determined by the shapes of the luminous parts of the atmosphere and a viewer's position . Auroras change with time. Over the night they begin with glows and progress toward coronas, although they may not reach them. They tend to fade in
15982-548: Was 16.9, compared with 27.1% nationally. Although some people chose not to answer the census's question about religious affiliation, 67.6% had no religion, 23.5% were Christian , 0.7% were Buddhist and 2.9% had other religions. Of those at least 15 years old, 84 (23.7%) people had a bachelor's or higher degree, and 63 (17.8%) people had no formal qualifications. The median income was $ 33,500, compared with $ 31,800 nationally. 57 people (16.1%) earned over $ 70,000 compared to 17.2% nationally. The employment status of those at least 15
16113-527: Was added to the service in December 2004. However, within two weeks of beginning service, the vessel was sold to Fullers Northland for service in the Bay of Islands , after Fullers suffered the loss of a vessel. Real Journeys bought out their partners to take complete control of the Stewart Island ferry service in May 2005. In 2015, responding to proposals for subsidised travel to Stewart Island for senior citizens,
16244-456: Was built to the new "standard" narrow gauge. Colonial Treasurer (and later Premier) Julius Vogel launched his Great Public Works policy of immigration and public works schemes of the 1870s, borrowing the massive sum of 10 million pounds, to develop significant infrastructure of roads, railways, and communications, all administered by the central government. This diminished the power of the provinces greatly. The provinces were finally abolished by
16375-534: Was first officer on the Pegasus , which visited in 1809, and he charted the large south-eastern harbour that now bears the ship's name ( Port Pegasus ) and determined the northern points of the island, proving that it was an island. In 1824, he initiated plans in England to establish a timber, flax and trading settlement at Stewart Island and sailed there in 1826, with it becoming known as Stewart's Island . In 1841,
16506-405: Was made by Venture Southland, an agency responsible for the region's economic and community development initiatives and tourism promotion, with the aim of attracting more visitors, particularly in the winter period. Rakiura National Park is the 14th of New Zealand's national parks and was officially opened on 9 March 2002. The park covers close to 1,400 square kilometres (540 sq mi), which
16637-789: Was part of the Otago Province . In local government today, Stewart Island is represented by one councilor on the Southland District Council . There is a Stewart Island/Rakiura Community Board to serve as the link between the community and the District Council. At the Southland Regional Council , it is part of the Invercargill-Rakiura ward. Stewart Island shares with some other islands a certain relaxation in some of
16768-528: Was planned. In the interim, the government ship Matai replaced the Wairua . By 1960, a new vessel to take over the Foveaux Strait service was under construction in Auckland. It was the largest ship to be constructed in New Zealand at that time, and was also named Wairua . The delivery voyage to Bluff was completed on 19 December 1961, and her first crossing of Foveaux Strait was on 20 December. The new Wairua
16899-483: Was that 207 (58.5%) people were employed full-time, 54 (15.3%) were part-time, and 3 (0.8%) were unemployed. Fishing has been, historically, the most important element of the economy of Stewart Island, and while it remains important, tourism has become the main source of income for islanders. There has also been some farming and forestry. From 1841 to 1853, Stewart Island was governed as New Leinster Province , then as part of New Munster Province . From 1853 onwards, it
17030-416: Was the first vessel in New Zealand to be fitted with anti-roll capabilities. The service to Stewart Island was twice a week during winter, and three times a week during summer. By 1985, the accumulated losses in operating the Wairua on the Foveaux Strait service over the previous 10 years totalled $ 6 million. The Minister of Transport , Richard Prebble , announced that the losses could not continue, and that
17161-424: Was to them an unknown type of aurora which they named " STEVE ", for "Strong Thermal Emission Velocity Enhancement". STEVE is not an aurora but is caused by a 25 km (16 mi) wide ribbon of hot plasma at an altitude of 450 km (280 mi), with a temperature of 3,000 °C (3,270 K; 5,430 °F) and flowing at a speed of 6 km/s (3.7 mi/s) (compared to 10 m/s (33 ft/s) outside
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