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86-519: The exceptionally sparse gas of the Local Bubble is the result of supernovae that exploded within the past ten to twenty million years. Geminga , a pulsar in the constellation Gemini , was once thought to be the remnant of a single supernova that created the Local Bubble, but now multiple supernovae in subgroup B1 of the Pleiades moving group are thought to have been responsible, becoming

172-412: A journal article came the following year in a publication by Knut Lundmark , who may have coined it independently. Compared to a star's entire history, the visual appearance of a supernova is very brief, sometimes spanning several months, so that the chances of observing one with the naked eye are roughly once in a lifetime. Only a tiny fraction of the 100  billion stars in a typical galaxy have

258-453: A non-rotating star), it would no longer be able to support the bulk of its mass through electron degeneracy pressure and would begin to collapse. However, the current view is that this limit is not normally attained; increasing temperature and density inside the core ignite carbon fusion as the star approaches the limit (to within about 1%) before collapse is initiated. In contrast, for a core primarily composed of oxygen, neon and magnesium,

344-557: A one or two-letter designation. The first 26 supernovae of the year are designated with a capital letter from A to Z . Next, pairs of lower-case letters are used: aa , ab , and so on. Hence, for example, SN 2003C designates the third supernova reported in the year 2003. The last supernova of 2005, SN 2005nc, was the 367th (14 × 26 + 3 = 367). Since 2000, professional and amateur astronomers have been finding several hundred supernovae each year (572 in 2007, 261 in 2008, 390 in 2009; 231 in 2013). Historical supernovae are known simply by

430-512: A paper in the journal Nature found that observations and modelling had determined that the action of the expanding surface of the bubble had collected gas and debris and was responsible for the formation of all young, nearby stars. These new stars are typically in molecular clouds like the Taurus molecular cloud and the open star cluster Pleiades . On earth several radioactive isotopes were connected to supernovae occurring relative nearby to

516-675: A rare type of very fast supernova with unusually strong calcium lines in their spectra. Models suggest they occur when material is accreted from a helium -rich companion rather than a hydrogen -rich star. Because of helium lines in their spectra, they can resemble type Ib supernovae, but are thought to have very different progenitors. The supernovae of type II can also be sub-divided based on their spectra. While most type II supernovae show very broad emission lines which indicate expansion velocities of many thousands of kilometres per second , some, such as SN 2005gl , have relatively narrow features in their spectra. These are called type IIn, where

602-581: A remnant supershell . Other research suggests that the subgroups Lower Centaurus–Crux (LCC) and Upper Centaurus–Lupus (UCL), of the Scorpius–Centaurus association created both the local bubble and the Loop I Bubble. With LCC being responsible for the Local Bubble and UCL being responsible for the Loop I Bubble. It was found that 14 to 20 supernovae originated from LCC and UCL, which could have formed these bubbles. The Solar System has been traveling through

688-703: A stellar companion to raise its core temperature enough to ignite carbon fusion , at which point it undergoes runaway nuclear fusion, completely disrupting it. There are three avenues by which this detonation is theorised to happen: stable accretion of material from a companion, the collision of two white dwarfs, or accretion that causes ignition in a shell that then ignites the core. The dominant mechanism by which type Ia supernovae are produced remains unclear. Despite this uncertainty in how type Ia supernovae are produced, type Ia supernovae have very uniform properties and are useful standard candles over intergalactic distances. Some calibrations are required to compensate for

774-474: A supernova's spectrum contains lines of hydrogen (known as the Balmer series in the visual portion of the spectrum) it is classified Type II ; otherwise it is Type I . In each of these two types there are subdivisions according to the presence of lines from other elements or the shape of the light curve (a graph of the supernova's apparent magnitude as a function of time). Type I supernovae are subdivided on

860-449: Is a dimensionless measure of the spectrum's frequency shift. High redshift searches for supernovae usually involve the observation of supernova light curves. These are useful for standard or calibrated candles to generate Hubble diagrams and make cosmological predictions. Supernova spectroscopy, used to study the physics and environments of supernovae, is more practical at low than at high redshift. Low redshift observations also anchor

946-531: Is a powerful and luminous explosion of a star . A supernova occurs during the last evolutionary stages of a massive star , or when a white dwarf is triggered into runaway nuclear fusion . The original object, called the progenitor , either collapses to a neutron star or black hole , or is completely destroyed to form a diffuse nebula . The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. The last supernova directly observed in

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1032-599: Is commonly accepted to have occurred in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny . The Australian James Kerguelen Robinson (1859–1914) was the first human born in the Antarctic, on board the sealing ship Offley in the Gulf of Morbihan (Royal Sound then), Kerguelen Island on 11 March 1859. The first human born and raised on an Antarctic island

1118-546: Is credited to the Spaniard Gabriel de Castilla , who reported seeing distant southern snow-capped mountains in 1603. The first Antarctic land discovered was the island of South Georgia , visited by the English merchant Anthony de la Roché in 1675. Although such myths and speculation about a Terra Australis ("Southern Land") date back to antiquity, the first confirmed sighting of the continent of Antarctica

1204-500: Is debated and several alternative explanations, such as tidal disruption of a star by a black hole, have been suggested. SN 2013fs was recorded three hours after the supernova event on 6 October 2013, by the Intermediate Palomar Transient Factory . This is among the earliest supernovae caught after detonation, and it is the earliest for which spectra have been obtained, beginning six hours after

1290-454: Is generated, with matter reaching velocities on the order of 5,000–20,000 km/s , or roughly 3% of the speed of light. There is also a significant increase in luminosity, reaching an absolute magnitude of −19.3 (or 5 billion times brighter than the Sun), with little variation. The model for the formation of this category of supernova is a close binary star system. The larger of the two stars

1376-549: Is much variation in this type of event, and, in many cases, there may be no supernova at all, in which case they will have a less luminous light curve than the more normal SN type Ia. Abnormally bright type Ia supernovae occur when the white dwarf already has a mass higher than the Chandrasekhar limit, possibly enhanced further by asymmetry, but the ejected material will have less than normal kinetic energy. This super-Chandrasekhar-mass scenario can occur, for example, when

1462-579: Is required. It is therefore important to discover them well before they reach their maximum. Amateur astronomers , who greatly outnumber professional astronomers, have played an important role in finding supernovae, typically by looking at some of the closer galaxies through an optical telescope and comparing them to earlier photographs. Toward the end of the 20th century, astronomers increasingly turned to computer-controlled telescopes and CCDs for hunting supernovae. While such systems are popular with amateurs, there are also professional installations such as

1548-414: Is the first to evolve off the main sequence , and it expands to form a red giant . The two stars now share a common envelope, causing their mutual orbit to shrink. The giant star then sheds most of its envelope, losing mass until it can no longer continue nuclear fusion . At this point, it becomes a white dwarf star, composed primarily of carbon and oxygen. Eventually, the secondary star also evolves off

1634-746: The 60°S latitude . The Treaty area covers Antarctica and the archipelagos of the Balleny Islands , Peter I Island , Scott Island , the South Orkney Islands , and the South Shetland Islands . However, this area does not include the Antarctic Convergence , a transition zone where the cold waters of the Southern Ocean collide with the warmer waters of the north, forming a natural border to

1720-530: The Andromeda Galaxy . A second supernova, SN 1895B , was discovered in NGC 5253 a decade later. Early work on what was originally believed to be simply a new category of novae was performed during the 1920s. These were variously called "upper-class Novae", "Hauptnovae", or "giant novae". The name "supernovae" is thought to have been coined by Walter Baade and Zwicky in lectures at Caltech in 1931. It

1806-518: The Chandrasekhar limit ; electron capture ; pair-instability ; or photodisintegration . The table below lists the known reasons for core collapse in massive stars, the types of stars in which they occur, their associated supernova type, and the remnant produced. The metallicity is the proportion of elements other than hydrogen or helium, as compared to the Sun. The initial mass is the mass of

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1892-570: The Eta Carinae Great Outburst was noted. Supernovae in M101 (1909) and M83 (1923 and 1957) were also suggested as possible type IV or type V supernovae. These types would now all be treated as peculiar type II supernovae (IIpec), of which many more examples have been discovered, although it is still debated whether SN 1961V was a true supernova following an LBV outburst or an impostor. Supernova type codes, as summarised in

1978-664: The Katzman Automatic Imaging Telescope . The Supernova Early Warning System (SNEWS) project uses a network of neutrino detectors to give early warning of a supernova in the Milky Way galaxy. Neutrinos are subatomic particles that are produced in great quantities by a supernova, and they are not significantly absorbed by the interstellar gas and dust of the galactic disk. Supernova searches fall into two classes: those focused on relatively nearby events and those looking farther away. Because of

2064-670: The Local Interstellar Cloud , which might be related to the formation of the Local Bubble. Launched in February ;2003 and active until April 2008, a small space observatory called Cosmic Hot Interstellar Plasma Spectrometer (CHIPS or CHIPSat) examined the hot gas within the Local Bubble. The Local Bubble was also the region of interest for the Extreme Ultraviolet Explorer mission (1992–2001), which examined hot EUV sources within

2150-535: The Milky Way was Kepler's Supernova in 1604, appearing not long after Tycho's Supernova in 1572, both of which were visible to the naked eye . The remnants of more recent supernovae have been found, and observations of supernovae in other galaxies suggest they occur in the Milky Way on average about three times every century. A supernova in the Milky Way would almost certainly be observable through modern astronomical telescopes. The most recent naked-eye supernova

2236-672: The Southern Hemisphere , of which 5.5 percent (14 million km ) is the surface area of the Antarctica continent itself. All of the land and ice shelves south of 60°S latitude are administered under the Antarctic Treaty System . Biogeographically , the Antarctic realm is one of eight biogeographic realms on Earth's land surface. Climate change in Antarctica is particularly important because

2322-674: The Sun . The Loop I Bubble contains the star Antares (also known as α Sco, or Alpha Scorpii), as shown on the diagram above right. Several tunnels connect the cavities of the Local Bubble with the Loop ;I Bubble, called the "Lupus Tunnel". Other bubbles which are adjacent to the Local Bubble are the Loop II Bubble and the Loop III Bubble . In 2019, researchers found interstellar iron in Antarctica which they relate to

2408-413: The expansion of the universe , the distance to a remote object with a known emission spectrum can be estimated by measuring its Doppler shift (or redshift ); on average, more-distant objects recede with greater velocity than those nearby, and so have a higher redshift. Thus the search is split between high redshift and low redshift, with the boundary falling around a redshift range of z=0.1–0.3, where z

2494-428: The galactic plane , becoming somewhat egg-shaped or elliptical, and may widen above and below the galactic plane, becoming shaped like an hourglass. It abuts other bubbles of less dense interstellar medium (ISM), including, in particular, the Loop I Bubble. The Loop I Bubble was cleared, heated and maintained by supernovae and stellar winds in the Scorpius–Centaurus association , some 500 light years from

2580-533: The plural form supernovae ( /- v iː / ) or supernovas and is often abbreviated as SN or SNe. It is derived from the Latin word nova , meaning ' new ' , which refers to what appears to be a temporary new bright star. Adding the prefix "super-" distinguishes supernovae from ordinary novae, which are far less luminous. The word supernova was coined by Walter Baade and Fritz Zwicky , who began using it in astrophysics lectures in 1931. Its first use in

2666-487: The speed of light . This drives an expanding shock wave into the surrounding interstellar medium , sweeping up an expanding shell of gas and dust observed as a supernova remnant. Supernovae are a major source of elements in the interstellar medium from oxygen to rubidium . The expanding shock waves of supernovae can trigger the formation of new stars . Supernovae are a major source of cosmic rays . They might also produce gravitational waves . The word supernova has

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2752-431: The "n" stands for "narrow". A few supernovae, such as SN 1987K and SN 1993J , appear to change types: they show lines of hydrogen at early times, but, over a period of weeks to months, become dominated by lines of helium. The term "type IIb" is used to describe the combination of features normally associated with types II and Ib. Type II supernovae with normal spectra dominated by broad hydrogen lines that remain for

2838-669: The Antarctic Convergence area, while the Isla Grande de Tierra del Fuego , Falkland Islands , Isla de los Estados , Hornos Island with Cape Horn , Diego Ramírez Islands , Campbell Island , Macquarie Island , Amsterdam and Saint Paul Islands, Crozet Islands , Prince Edward Islands , Gough Island , and Tristan da Cunha group remain north of the Convergence and thus outside the Antarctic region. A variety of animals live in Antarctica for at least some of

2924-734: The South Georgia and the South Sandwich Islands Marine Protection Area created in 2012. The latter exceeds the surface area of another vast protected territory, the Greenland National Park 's 972,000 km (375,000 sq mi). (While the Ross Sea Marine Protection Area established in 2016 is still larger at 1.55 million km , its protection is set to expire in 35 years. ) To protect

3010-562: The West Antarctic, the ocean has warmed by 1 °C (1.8 °F) since 1955. The fresh, 1100-1500 billion tons (GT) per year of meltwater from the ice dilutes the saline Antarctic bottom water , weakening the lower cell of the Southern Ocean overturning circulation (SOOC). According to some research, a full collapse of the SOOC may occur a between 1.7 °C (3.1 °F) and 3 °C (5.4 °F) of global warming, although

3096-615: The actual explosion. The star is located in a spiral galaxy named NGC 7610 , 160 million light-years away in the constellation of Pegasus. The supernova SN 2016gkg was detected by amateur astronomer Victor Buso from Rosario , Argentina, on 20 September 2016. It was the first time that the initial "shock breakout" from an optical supernova had been observed. The progenitor star has been identified in Hubble Space Telescope images from before its collapse. Astronomer Alex Filippenko noted: "Observations of stars in

3182-678: The area, all Antarctic ships over 500 tonnes are subject to mandatory regulations under the Polar Code , adopted by the International Maritime Organization (in force since 1 January 2017). Climate change caused by greenhouse gas emissions from human activities occurs everywhere on Earth, and while Antarctica is less vulnerable to it than any other continent, climate change in Antarctica has been observed. Since 1959, there has been an average temperature increase of >0.05 °C/decade since 1957 across

3268-688: The basis of their spectra, with type Ia showing a strong ionised silicon absorption line. Type I supernovae without this strong line are classified as type Ib and Ic, with type Ib showing strong neutral helium lines and type Ic lacking them. Historically, the light curves of type I supernovae were seen as all broadly similar, too much so to make useful distinctions. While variations in light curves have been studied, classification continues to be made on spectral grounds rather than light-curve shape. A small number of type Ia supernovae exhibit unusual features, such as non-standard luminosity or broadened light curves, and these are typically categorised by referring to

3354-430: The bubble. Sources beyond the edge of the bubble were identified but attenuated by the denser interstellar medium. In 2019, the first 3D map of the Local Bubble has been reported using the observations of diffuse interstellar bands. In 2020, the shape of the dusty envelope surrounding the Local Bubble was retrieved and modeled from 3D maps of the dust density obtained from stellar extinction data. In January 2022,

3440-543: The capacity to become a supernova, the ability being restricted to those having high mass and those in rare kinds of binary star systems with at least one white dwarf . The earliest record of a possible supernova, known as HB9, was likely viewed by an unknown prehistoric people of the Indian subcontinent and recorded on a rock carving in the Burzahama region of Kashmir , dated to 4500 ± 1000  BC . Later, SN 185

3526-402: The collapsing white dwarf will typically form a neutron star . In this case, only a fraction of the star's mass will be ejected during the collapse. Within a few seconds of the collapse process, a substantial fraction of the matter in the white dwarf undergoes nuclear fusion, releasing enough energy (1– 2 × 10   J ) to unbind the star in a supernova. An outwardly expanding shock wave

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3612-588: The continent of Antarctica , the Kerguelen Plateau , and other island territories located on the Antarctic Plate or south of the Antarctic Convergence . The Antarctic region includes the ice shelves , waters, and all the island territories in the Southern Ocean situated south of the Antarctic Convergence , a zone approximately 32 to 48 km (20 to 30 mi) wide and varying in latitude seasonally. The region covers some 20 percent of

3698-496: The continent, although it had been uneven. West Antarctica warmed by over 0.1 °C/decade from the 1950s to the 2000s, and the exposed Antarctic Peninsula has warmed by 3 °C (5.4 °F) since the mid-20th century. The colder, stabler East Antarctica had been experiencing cooling until the 2000s. Around Antarctica, the Southern Ocean has absorbed more oceanic heat than any other ocean, and has seen strong warming at depths below 2,000 m (6,600 ft). Around

3784-454: The core against its own gravity; passing this threshold is the cause of all types of supernova except type Ia. The collapse may cause violent expulsion of the outer layers of the star resulting in a supernova. However, if the release of gravitational potential energy is insufficient, the star may instead collapse into a black hole or neutron star with little radiated energy. Core collapse can be caused by several different mechanisms: exceeding

3870-400: The distance to their host galaxies. A second model for the formation of type Ia supernovae involves the merger of two white dwarf stars, with the combined mass momentarily exceeding the Chandrasekhar limit. This is sometimes referred to as the double-degenerate model, as both stars are degenerate white dwarfs. Due to the possible combinations of mass and chemical composition of the pair there

3956-401: The earliest example showing similar features. For example, the sub-luminous SN 2008ha is often referred to as SN 2002cx -like or class Ia-2002cx. A small proportion of type Ic supernovae show highly broadened and blended emission lines which are taken to indicate very high expansion velocities for the ejecta. These have been classified as type Ic-BL or Ic-bl. Calcium-rich supernovae are

4042-411: The event sufficiently for it to go unnoticed. The situation for Cassiopeia A is less clear; infrared light echoes have been detected showing that it was not in a region of especially high extinction. SN's identification With the development of the astronomical telescope , observation and discovery of fainter and more distant supernovae became possible. The first such observation was of SN 1885A in

4128-558: The extra mass is supported by differential rotation . There is no formal sub-classification for non-standard type Ia supernovae. It has been proposed that a group of sub-luminous supernovae that occur when helium accretes onto a white dwarf should be classified as type Iax . This type of supernova may not always completely destroy the white dwarf progenitor and could leave behind a zombie star . One specific type of supernova originates from exploding white dwarfs, like type Ia, but contains hydrogen lines in their spectra, possibly because

4214-451: The first moments they begin exploding provide information that cannot be directly obtained in any other way." The James Webb Space Telescope (JWST) has significantly advanced our understanding of supernovae by identifying around 80 new instances through its JWST Advanced Deep Extragalactic Survey (JADES) program. This includes the most distant spectroscopically confirmed supernova at a redshift of 3.6, indicating its explosion occurred when

4300-613: The fishing vessels, as well as satellite surveillance. The islands situated between 60°S latitude parallel to the south and the Antarctic Convergence to the north and their respective 200-nautical-mile (370 km) exclusive economic zones fall under the national jurisdiction of the countries that possess them: South Georgia and the South Sandwich Islands (United Kingdom), Bouvet Island (Norway), and Heard and McDonald Islands (Australia). Kerguelen Islands (France; also an EU Overseas territory) are situated in

4386-752: The full effects are expected to occur over multiple centuries; these include less precipitation in the Southern Hemisphere but more in the Northern Hemisphere , an eventual decline of fisheries in the Southern Ocean and a potential collapse of certain marine ecosystems . While many Antarctic species remain undiscovered, there are documented increases in Antarctic flora , and large fauna such as penguins are already having difficulty retaining suitable habitat. On ice-free land, permafrost thaws release greenhouse gases and formerly frozen pollution. The first recorded sighting of Antarctica

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4472-439: The gradual change in properties or different frequencies of abnormal luminosity supernovae at high redshift, and for small variations in brightness identified by light curve shape or spectrum. There are several means by which a supernova of this type can form, but they share a common underlying mechanism. If a carbon - oxygen white dwarf accreted enough matter to reach the Chandrasekhar limit of about 1.44 solar masses (for

4558-453: The harsh climate was a major contributor towards species richness, but multiple correlations have been found with area, temperature, remoteness of islands, and food chain stability. For example, herbivorous insects are poor in number due to low plant richness, and likewise, indigenous bird numbers are related to insects, which are a major food source. The Antarctic hosts the world's largest protected area comprising 1.07 million km ,

4644-564: The increasing number of discoveries has regularly led to the additional use of three-letter designations. After zz comes aaa, then aab, aac, and so on. For example, the last supernova retained in the Asiago Supernova Catalogue ; when it was terminated on 31 December 2017 bears the designation SN 2017jzp. Astronomers classify supernovae according to their light curves and the absorption lines of different chemical elements that appear in their spectra . If

4730-431: The life of the decline are classified on the basis of their light curves. The most common type shows a distinctive "plateau" in the light curve shortly after peak brightness where the visual luminosity stays relatively constant for several months before the decline resumes. These are called type II-P referring to the plateau. Less common are type II-L supernovae that lack a distinct plateau. The "L" signifies "linear" although

4816-437: The light curve is extremely consistent across normal type Ia supernovae, having a maximum absolute magnitude of about −19.3. This is because typical type Ia supernovae arise from a consistent type of progenitor star by gradual mass acquisition, and explode when they acquire a consistent typical mass, giving rise to very similar supernova conditions and behaviour. This allows them to be used as a secondary standard candle to measure

4902-487: The light curve is not actually a straight line. Supernovae that do not fit into the normal classifications are designated peculiar, or "pec". Zwicky defined additional supernovae types based on a very few examples that did not cleanly fit the parameters for type I or type II supernovae. SN 1961i in NGC 4303 was the prototype and only member of the type III supernova class, noted for its broad light curve maximum and broad hydrogen Balmer lines that were slow to develop in

4988-463: The low-distance end of the Hubble curve , which is a plot of distance versus redshift for visible galaxies. As survey programmes rapidly increase the number of detected supernovae, collated collections of observations (light decay curves, astrometry, pre-supernova observations, spectroscopy) have been assembled. The Pantheon data set, assembled in 2018, detailed 1048 supernovae. In 2021, this data set

5074-492: The main sequence to form a red giant. Matter from the giant is accreted by the white dwarf, causing the latter to increase in mass. The exact details of initiation and of the heavy elements produced in the catastrophic event remain unclear. Type Ia supernovae produce a characteristic light curve—the graph of luminosity as a function of time—after the event. This luminosity is generated by the radioactive decay of nickel -56 through cobalt -56 to iron -56. The peak luminosity of

5160-420: The melting of the Antarctic ice sheet has a high potential to add to the global sea level rise . Further, this melting also disrupts the flow of Southern Ocean overturning circulation , which would have significant effects on the local climate and marine ecosystem functioning.There is no permanent country in Antarctica . As defined by the Antarctic Treaty System , the Antarctic region is everything south of

5246-469: The most distant supernovae observed in 2003 appeared dimmer than expected. This supports the view that the expansion of the universe is accelerating . Techniques were developed for reconstructing supernovae events that have no written records of being observed. The date of the Cassiopeia A supernova event was determined from light echoes off nebulae , while the age of supernova remnant RX J0852.0-4622

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5332-607: The most popular destinations being the Antarctic Peninsula area (especially the South Shetland Islands ) and South Georgia Island . In December 2009, the growth of tourism , with consequences for both the ecology and the safety of the travellers in its great and remote wilderness, was noted at a conference in New Zealand by experts from signatories to the Antarctic Treaty . The definitive results of

5418-564: The naked eye, had a notable influence on the development of astronomy in Europe because they were used to argue against the Aristotelian idea that the universe beyond the Moon and planets was static and unchanging. Johannes Kepler began observing SN 1604 at its peak on 17 October 1604, and continued to make estimates of its brightness until it faded from naked eye view a year later. It was

5504-529: The newly ejected material. Antarctic The Antarctic ( / æ n ˈ t ɑːr t ɪ k / or / æ n ˈ t ɑːr k t ɪ k / , American English also / æ n t ˈ ɑːr t ɪ k / or / æ n t ˈ ɑːr k t ɪ k / ; commonly / æ ˈ n ɑːr t ɪ k / ) is a polar region around Earth 's South Pole , opposite the Arctic region around the North Pole . The Antarctic comprises

5590-586: The region currently occupied by the Local Bubble for the last five to ten million years. Its current location lies in the Local Interstellar Cloud (LIC), a minor region of denser material within the Bubble. The LIC formed where the Local Bubble and the Loop I Bubble met. The gas within the LIC has a density of approximately 0.3 atoms per cubic centimeter. The Local Bubble is not spherical, but seems to be narrower in

5676-640: The region. Because the Convergence changes seasonally, the Convention for the Conservation of Antarctic Marine Living Resources approximates the Convergence line by joining specified points along parallels of latitude and meridians of longitude . The implementation of the convention is managed through an international commission headquartered in Hobart , Australia, by an efficient system of annual fishing quotas, licenses, and international inspectors on

5762-491: The second supernova to be observed in a generation, after Tycho Brahe observed SN 1572 in Cassiopeia . There is some evidence that the youngest known supernova in our galaxy, G1.9+0.3 , occurred in the late 19th century, considerably more recently than Cassiopeia A from around 1680. Neither was noted at the time. In the case of G1.9+0.3, high extinction from dust along the plane of the galactic disk could have dimmed

5848-585: The solar system. The most common source is found in deep sea ferromanganese crusts . Such nodules are constantly growing and deposits iron, manganese and other elements. Samples are divided into layers which are dated for example with Beryllium-10 . Some of these layers have higher concentrations of radioactive isotopes. The isotope most commonly associated with supernovae on earth is Iron-60 from deep sea sediments , Antarctic snow, and lunar soil . Other isotopes are Manganese-53 and Plutonium-244 from deep sea materials. Supernova-originated Aluminium-26 , which

5934-467: The southernmost. In late 1977, Silvia Morella de Palma, who was then seven months pregnant, was airlifted to Esperanza Base , in order to complete her pregnancy in the base. The airlift was a part of the Argentine solutions to the sovereignty dispute over territory in Antarctica. Emilio was automatically granted Argentine citizenship by the government since his parents were both Argentine citizens, and he

6020-452: The spectrum. SN 1961f in NGC 3003 was the prototype and only member of the type IV class, with a light curve similar to a type II-P supernova, with hydrogen absorption lines but weak hydrogen emission lines . The type V class was coined for SN 1961V in NGC 1058 , an unusual faint supernova or supernova impostor with a slow rise to brightness, a maximum lasting many months, and an unusual emission spectrum. The similarity of SN 1961V to

6106-514: The star prior to the supernova event, given in multiples of the Sun's mass, although the mass at the time of the supernova may be much lower. Type IIn supernovae are not listed in the table. They can be produced by various types of core collapse in different progenitor stars, possibly even by type Ia white dwarf ignitions, although it seems that most will be from iron core collapse in luminous supergiants or hypergiants (including LBVs). The narrow spectral lines for which they are named occur because

6192-469: The supernova is expanding into a small dense cloud of circumstellar material. It appears that a significant proportion of supposed type IIn supernovae are supernova impostors, massive eruptions of LBV-like stars similar to the Great Eruption of Eta Carinae . In these events, material previously ejected from the star creates the narrow absorption lines and causes a shock wave through interaction with

6278-409: The table above, are taxonomic : the type number is based on the light observed from the supernova, not necessarily its cause. For example, type Ia supernovae are produced by runaway fusion ignited on degenerate white dwarf progenitors, while the spectrally similar type Ib/c are produced from massive stripped progenitor stars by core collapse. A white dwarf star may accumulate sufficient material from

6364-820: The universe was merely 1.8 billion years old. These findings offer crucial insights into the early universe's stellar evolution and the frequency of supernovae during its formative years. Because supernovae are relatively rare events within a galaxy, occurring about three times a century in the Milky Way, obtaining a good sample of supernovae to study requires regular monitoring of many galaxies. Today, amateur and professional astronomers are finding several hundred every year, some when near maximum brightness, others on old astronomical photographs or plates. Supernovae in other galaxies cannot be predicted with any meaningful accuracy. Normally, when they are discovered, they are already in progress. To use supernovae as standard candles for measuring distance, observation of their peak luminosity

6450-484: The white dwarf is surrounded by an envelope of hydrogen-rich circumstellar material . These supernovae have been dubbed type Ia/IIn , type Ian , type IIa and type IIan . The quadruple star HD 74438 , belonging to the open cluster IC 2391 the Vela constellation , has been predicted to become a non-standard type Ia supernova. Very massive stars can undergo core collapse when nuclear fusion becomes unable to sustain

6536-460: The year they occurred: SN 185, SN 1006, SN 1054, SN 1572 (called Tycho's Nova ) and SN 1604 ( Kepler's Star ). Since 1885 the additional letter notation has been used, even if there was only one supernova discovered that year (for example, SN 1885A, SN 1907A, etc.); this last happened with SN 1947A. SN , for SuperNova, is a standard prefix. Until 1987, two-letter designations were rarely needed; since 1988, they have been needed every year. Since 2016,

6622-413: The year, including: Most of the Antarctica continent is permanently covered by ice and snow, leaving less than 1 percent of the land exposed. There are only two species of flowering plant, Antarctic hair grass and Antarctic pearlwort , but a range of mosses , liverworts , lichens and macrofungi . Biodiversity among terrestrial flora and fauna is low on the islands: studies have theorized that

6708-897: The younger peak might have created the pulsar PSR B1706-16 and turned Zeta Ophiuchi into a runaway star . Both originated from UCL and were released by a supernova 1.78 ± 0.21 Million years ago. Another explanation for the older peak is that it was produced by one supernova in the Tucana-Horologium association 7-9 Million years ago. Solar System   → Local Interstellar Cloud   → Local Bubble   → Gould Belt   → Orion Arm   → Milky Way   → Milky Way subgroup   → Local Group → Local Sheet → Virgo Supercluster → Laniakea Supercluster   → Local Hole   → Observable universe   → Universe Each arrow ( → ) may be read as "within" or "part of". Supernova A supernova ( pl. : supernovae or supernovas )

6794-532: Was SN 1987A , which was the explosion of a blue supergiant star in the Large Magellanic Cloud , a satellite galaxy of the Milky Way. Theoretical studies indicate that most supernovae are triggered by one of two basic mechanisms: the sudden re-ignition of nuclear fusion in a white dwarf , or the sudden gravitational collapse of a massive star's core . Supernovae can expel several solar masses of material at speeds up to several percent of

6880-661: Was Solveig Gunbjørg Jacobsen born on 8 October 1913 in Grytviken , South Georgia. Emilio Marcos Palma (born 7 January 1978) is an Argentine man who was the first documented person born on the continent of Antarctica at the Esperanza Base . His father, Captain Jorge Palma, was head of the Argentine Army detachment at the base. While ten people have been born in Antarctica since, Palma's birthplace remains

6966-449: Was born in the claimed Argentine Antarctica . Palma can be considered to be the first native Antarctican. The Antarctic region had no indigenous population when first discovered, and its present inhabitants comprise a few thousand transient scientific and other personnel working on tours of duty at the several dozen research stations maintained by various countries. However, the region is visited by more than 40,000 tourists annually,

7052-561: Was documented by Chinese astronomers in 185 AD. The brightest recorded supernova was SN 1006 , which was observed in AD 1006 in the constellation of Lupus . This event was described by observers in China, Japan, Iraq, Egypt and Europe. The widely observed supernova SN 1054 produced the Crab Nebula . Supernovae SN 1572 and SN 1604 , the latest Milky Way supernovae to be observed with

7138-464: Was estimated from temperature measurements and the gamma ray emissions from the radioactive decay of titanium-44 . The most luminous supernova ever recorded is ASASSN-15lh , at a distance of 3.82 gigalight-years . It was first detected in June 2015 and peaked at 570 billion  L ☉ , which is twice the bolometric luminosity of any other known supernova. The nature of this supernova

7224-495: Was expanded to 1701 light curves for 1550 supernovae taken from 18 different surveys, a 50% increase in under 3 years. Supernova discoveries are reported to the International Astronomical Union 's Central Bureau for Astronomical Telegrams , which sends out a circular with the name it assigns to that supernova. The name is formed from the prefix SN , followed by the year of discovery, suffixed with

7310-477: Was expected from cosmic ray studies, was not confirmed. Iron-60 and Manganese-53 have a peak 1.7–3.2 Million years ago and Iron-60 has a second peak 6.5–8.7 Million years ago. The older peak likely originated when the solar system moved through the Orion-Eridanus superbubble and the younger peak was generated when the solar system entered the local bubble 4.5 Million years ago. One of the supernovae creating

7396-503: Was used, as "super-Novae", in a journal paper published by Knut Lundmark in 1933, and in a 1934 paper by Baade and Zwicky. By 1938, the hyphen was no longer used and the modern name was in use. American astronomers Rudolph Minkowski and Fritz Zwicky developed the modern supernova classification scheme beginning in 1941. During the 1960s, astronomers found that the maximum intensities of supernovae could be used as standard candles , hence indicators of astronomical distances. Some of

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