title: Arikara

text: The Arikara faced many challenges during the first quarter of the 19th century: Reduced numbers, competition from white traders, and military pressure from the Lakota and other groups of Sioux. Alliances shifted constantly. The Arikara joined old foes the Sioux in raids on Mandan and Hidatsa Indians. Later they negotiated for peace with both village tribes.


title: Arikara

text: Due to their reduced numbers, the Arikara started to live closer to the Mandan and Hidatsa in the same area for mutual protection. They migrated gradually from present-day Nebraska and South Dakota into North Dakota. The remainder of the group was encountered in 1804 by the Lewis and Clark Expedition.


title: Arikara

text: The first Arikara delegation left for the capital, Washington, DC, in April 1805, urged by the Lewis and Clark Expedition. Chief Ankedoucharo became ill during his stay and died in Washington. The delegates blamed the whites for the chief's death. That was one reason why the Arikara for the next decades were "notoriously hostile to white Americans".


title: Arikara

text: On June 2, 1823, the Arikara attacked a group of 70 trappers led by William Henry Ashley of the Henry/Ashley Company. The trappers were camped near an Arikara village at the mouth of Grand River (north of present-day Mobridge, South Dakota). Fourteen trappers died and 10 were wounded, including Hugh Glass, memorialized in the 1954 biographical novel "Lord Grizzly" by Frederick Manfred, the 2002 historical fiction novel "The Revenant: A Novel of Revenge" by Michael Punke, and the 2015 film "The Revenant", an adaptation of Punke's book.


title: Arikara

text: Colonel Henry Leavenworth left Fort Atkinson (now in Nebraska) with 220 men. More than 700 Yankton, Yanktonai and Lakota Indians joined him in the United States' first Indian war west of the Missouri. The Arikara retreated to their fortified village. Soon the disappointed Sioux left the battlefield. The Arikara escaped at night, and angry fur traders set their empty lodges ablaze the next morning. "This was the only time in history that any of the Three Tribes fought in open warfare against the United States".


title: Arikara

text: The Bloody Hand and other Arikara chiefs signed a peace treaty with the United States (US) on July 18, 1825.


title: Arikara

text: In the winter/spring of 1833 members of the Arikara Tribe ambushed Hugh Glass, Hilain Menard and Colin Rose. "A hand-written notation made on the credit side of Menard's account book page states, 'Killed by the Rees near Fort Cass Spring 1833,'" Landry wrote in his article. "The word 'Rees' was mountaineer slang for the Arikara tribe." According to a letter written by John F. A. Sanford, an Indian agent, in a July 1833 letter to William Clark, superintendent of Indian Affairs. Landry includes the excerpt in his article."They scalped them and left part of the Scalps of each tied to poles on the grounds of the murder[.]"


title: Arikara

text: Years of indecision followed. The rootless Arikara lived near their southern "kinfolk," the Skidi Pawnee, for some years. They also tried their luck in hostile country far up on the Platte (now Nebraska), where Colonel Henry Dodge met them in 1835. Harassed by the numerous Sioux, the Arikara finally buried old enmity and befriended the Mandan and the Hidatsa in the late 1830s. The manager in the trading post Fort Clark observed in June 1838, how "the Rees, Mandans and Gros Ventres [Hidatsas] started out early" in a common bison hunt.


title: Arikara

text: Smallpox had struck the Upper Missouri tribes the year before (and would again in 1856). It decimated the Mandan. The surviving Arikara took over the almost empty Mandan village "Mitutanka" next to Fort Clark. The earth lodges stood until Yankton Sioux set them on fire in January 1839. The village was rebuilt by the Arikara, who lived there until 1861. Another Sioux attack—and the need for a trading post—made them leave the settlement for good.


title: Arikara

text: The goal of the United States in the Laramie Treaty of 1851 was to establish a permanent peace on most of the northern plains and to define tribal territories. The basic treaty area of the Arikara, the Hidatsa and the Mandan was a mutual territory north of Heart River, encircled on the east and north by the Missouri and on the west by Yellowstone River down to the mouth of Powder River. The Lakota had continued to press north after 1823, so they got treaty rights on the area along Grand River as well as other land south of Heart River.


title: Arikara

text: Peace was short-lived. As drawings collected by W. J. Hoffman of Hunkpapa Chief Running Antelope showed, in 1853 he already had killed four Arikara Indians. The next year the Three Tribes called for the U. S. Army to intervene; that request was repeated the next two decades.


title: Arikara

text: Arikara hunters were waylaid and had difficulties securing enough game and hides. A lengthy battle between an Arikara camp on hunt and several hundred Lakota took place in June 1858. The Arikara camp lost ten men, with 34 wounded.


title: Arikara

text: The Arikara built Star Village in the spring of 1862. They had to abandon it after a fierce fight with the Sioux a few months later. The Arikara crossed the Missouri and built new earth lodges and log houses near the common Mandan and Hidatsa village Like-a-Fishhook Village. The village was built outside the Three Tribes treaty area. "We, the Arikara, have been driven from our country on the other side of the Missouri River by the Sioux", declared chief White Shield in 1864.


title: Arikara

text: Like a Fishhook Village was not safe from devastation, strikes or raids for horses (and neither was the nearby trading post Fort Berthold II). Just before the end of 1862, some Sioux burned a part of the village. The affiliation of the Sioux is not always clear: Lakota, Yanktonai and "refugee" Santee Sioux from the Minnesota uprising sometimes attacked the Three Tribes. As always in intertribal warfare, there were interludes with peace - and conflicts with other Indian foes, as for example the Assiniboine.


title: Arikara

text: In 1869, the Three Tribes asked the United States for guns as protection against hostile Sioux, and they finally received 300 pieces.


title: Arikara

text: The Three Tribes sold a part of their southern treaty land, more or less already annexed by the Lakota, to the United States on April 12, 1870. At the same time, they got treaty on the area where Like a Fishhook Village was located.


title: Arikara

text: In June 1874, Colonel George Armstrong Custer in Fort Abraham Lincoln (now North Dakota) received an order to delay his Black Hills Expedition and stop a large war party of Lakota on its way to attack Like a Fishhook Village. "The Rees and Mandans should be protected same as white settlers", read the order from General Phil Sheridan. Custer failed and the Lakota killed five Arikara and one Mandan.


title: Arikara

text: During the Great Sioux War of 1876, some Arikara served as scouts for Custer in the Little Bighorn Campaign. The Arikara "supplied some of the most faithful and effective Indian scouts" for the Army during the war against the bands of Lakota roaming other peoples' territories in 1876-1877. "For tribes subject to Sioux pressure for decades, the combination of revenge and self-defense would constitute a powerful motivation" for joining the whites in actions like that. Custer's favorite scout, an Arikara known as Bloody Knife, fell during the Battle of the Little Bighorn in the Crow Indian Reservation (now Montana) in 1876.


title: Arikara

text: "Mandans, Arickarees and Gros Ventres" were among the first Indian children to arrive at Hampton Institute, a historically black college, in Virginia for schooling, in 1878.


title: Arikara

text: The Fort Berthold Indian Reservation got a new shape and size by agreement in 1886 (ratified in 1891). In 1910, the Three Tribes gave their consent to sale of land, so the reservation was reduced once more. The Arikara drifted away from Like a Fishhook Village. They raised and branded cattle instead of hunting buffalo. With the Dawes Act and "allotment in severalty" passed as another attempt at assimilation to European-American culture, each Arikara family was allotted a homestead of 160 acres in the early 1890s. The Arikara Indians were considered citizens of the United States—and no more tribal village dwellers.


title: Arikara

text: In the 2015 film "The Revenant", Arikara warriors act as major antagonists in the early part of the film. Trappers refer to them both by their proper name and as Ree, and the 1823 attack on Andrew Henry's trapping expedition is accurate. Furthermore, the production was noted for its efforts to reproduce Pawnee and Arikara speech as accurately as possible.


title: Therapy

text: A therapy or medical treatment (often abbreviated tx, Tx, or T) is the attempted remediation of a health problem, usually following a medical diagnosis.


title: Therapy

text: As a rule, each therapy has indications and contraindications. There are many different types of therapy. Not all therapies are effective. Many therapies can produce unwanted adverse effects.


title: Therapy

text: "Medical treatment" and "therapy" are generally considered synonyms. However, in the context of mental health, the term "therapy" may refer specifically to psychotherapy.


title: Therapy

text: Before the creating of therapy as a formal procedure, people told stories to one another to inform and assist about the world. The term "healing through words" was used over 3,500 years ago in Greek and Egyptian writing. The term psychotherapy was invented in the 19th century, and psychoanalysis was founded by Sigmund Freud under a decade later.


title: Therapy

text: The words care, therapy, treatment, and intervention overlap in a semantic field, and thus they can be synonymous depending on context. Moving rightward through that order, the connotative level of holism decreases and the level of specificity (to concrete instances) increases. Thus, in health care contexts (where its senses are always noncount), the word "care" tends to imply a broad idea of everything done to protect or improve someone's health (for example, as in the terms "preventive care" and "primary care", which connote ongoing action), although it sometimes implies a narrower idea (for example, in the simplest cases of wound care or postanesthesia care, a few particular steps are sufficient, and the patient's interaction with that provider is soon finished). In contrast, the word "intervention" tends to be specific and concrete, and thus the word is often countable; for example, one instance of cardiac catheterization is one intervention performed, and coronary care (noncount) can require a series of interventions (count). At the extreme, the piling on of such countable interventions amounts to interventionism, a flawed model of care lacking holistic circumspection—merely treating discrete problems (in billable increments) rather than maintaining health. "Therapy" and "treatment", in the middle of the semantic field, can connote either the holism of "care" or the discreteness of "intervention", with context conveying the intent in each use. Accordingly, they can be used in both noncount and count senses (for example, "therapy for chronic kidney disease can involve several dialysis treatments per week").


title: Therapy

text: The words "aceology" and "iamatology" are obscure and obsolete synonyms referring to the study of therapies.


title: Therapy

text: The English word "therapy" comes via Latin "therapīa" from and literally means "curing" or "healing".


title: Therapy

text: Therapy comes in different forms. These include, cognitive behavioral therapy, dialectical behavior therapy, mindful based cognitive therapy, physical therapy, etc. Therapists are here for use and used daily by many people. Therapist are trained to provide treatment to an individual or group. Therapy was invented in the 1800s and the founder was Franz Mesmer, the "Father of Western Psychotherapy". Sigmund Freud then comes into play and shows us the understanding depth of all the different types included in therapy. Therapy is used in many ways to shape and help reform a person. This type of treatment allows individuals to regain gain goals lost or wanting to accomplish. Many individuals come into therapy looking for ways to cope with issues and to receive an emotional release. For example, healing from trauma, in need of support, emotional issues, and many more. Allowing yourself to express your thoughts and feelings go a long way in therapy recovery, this is called the therapeutic process.


title: Therapy

text: Levels of care classify health care into categories of chronology, priority, or intensity, as follows:


title: Therapy

text: Treatment decisions often follow formal or informal algorithmic guidelines. Treatment options can often be ranked or prioritized into lines of therapy: first-line therapy, second-line therapy, third-line therapy, and so on. First-line therapy (sometimes referred to as induction therapy, primary therapy, or front-line therapy) is the first therapy that will be tried. Its priority over other options is usually either: (1) formally recommended on the basis of clinical trial evidence for its best-available combination of efficacy, safety, and tolerability or (2) chosen based on the clinical experience of the physician. If a first-line therapy either fails to resolve the issue or produces intolerable side effects, additional (second-line) therapies may be substituted or added to the treatment regimen, followed by third-line therapies, and so on.


title: Therapy

text: An example of a context in which the formalization of treatment algorithms and the ranking of lines of therapy is very extensive is chemotherapy regimens. Because of the great difficulty in successfully treating some forms of cancer, one line after another may be tried. In oncology the count of therapy lines may reach 10 or even 20.


title: Therapy

text: Often multiple therapies may be tried simultaneously (combination therapy or polytherapy). Thus combination chemotherapy is also called polychemotherapy, whereas chemotherapy with one agent at a time is called single-agent therapy or monotherapy.


title: Therapy

text: Adjuvant therapy is therapy given in addition to the primary, main, or initial treatment, but simultaneously (as opposed to second-line therapy). Neoadjuvant therapy is therapy that is begun before the main therapy. Thus one can consider surgical excision of a tumor as the first-line therapy for a certain type and stage of cancer even though radiotherapy is used before it; the radiotherapy is neoadjuvant (chronologically first but not primary in the sense of the main event). Premedication is conceptually not far from this, but the words are not interchangeable; cytotoxic drugs to put a tumor "on the ropes" before surgery delivers the "knockout punch" are called neoadjuvant chemotherapy, not premedication, whereas things like anesthetics or prophylactic antibiotics before dental surgery are called premedication.


title: Therapy

text: Step therapy or stepladder therapy is a specific type of prioritization by lines of therapy. It is controversial in American health care because unlike conventional decision-making about what constitutes first-line, second-line, and third-line therapy, which in the U.S. reflects safety and efficacy first and cost only according to the patient's wishes, step therapy attempts to mix cost containment by someone other than the patient (third-party payers) into the algorithm. Therapy freedom and the negotiation between individual and group rights are involved.


title: Mike Mills (director)

text: Michael Chadbourne Mills is an American film and music video director, writer and graphic designer. He is best known for his independent films, "Beginners" (2010), "20th Century Women" (2016), and "C'mon, C'mon" (2021). Mills received an Academy Award for Best Original Screenplay nomination for "20th Century Women".


title: Mike Mills (director)

text: Michael Chadbourne Mills was born in Berkeley, California, the son of Janet L. Dowd, a draftsperson, and Paul Chadbourne Mills, an art historian and museum director.


title: Mike Mills (director)

text: Mike Mills has created music videos for acts including Moby, Yoko Ono and Air. Air named the fifth song on their album "Talkie Walkie" after Mills.


title: Mike Mills (director)

text: He has also worked as a graphic designer on promotional material and album covers for such acts as Beastie Boys, Beck, Sonic Youth, They Might Be Giants, and Ol' Dirty Bastard. In addition he has created graphics for X-Girl, Marc Jacobs, and produces his own line of posters and fabrics called Humans by Mike Mills.


title: Mike Mills (director)

text: Mills played guitar and performed background vocals with the short-lived indie rock band Butter 08 along with Yuka Honda and Miho Hatori of Cibo Matto, Russell Simins of the Jon Spencer Blues Explosion, and Rick Lee of Skeleton Key. The band released one self-titled album in 1996 on the now defunct Grand Royal record label.


title: Mike Mills (director)

text: "Thumbsucker" (2005) was his feature-film directorial debut, for which he also created the film posters. In 2007, Mills filmed the feature-length documentary "Does Your Soul Have A Cold?", which explored the issues around the introduction of anti-depressants to Japanese culture. The film premiered at SXSW Festival and was part of IFC's documentary film series. He followed this up with "Beginners" in 2010.


title: Mike Mills (director)

text: His next feature film was "20th Century Women", starring Annette Bening, Greta Gerwig, Elle Fanning and Billy Crudup. The film had its world premiere at the New York Film Festival, and was released on December 28, 2016, by A24.


title: Mike Mills (director)

text: He has released some of his art/documentary photography works with the two books, "Gas Book 11" (2003) and "Humans" (2006). In 2009, the Berlin-based culture magazine 032c devoted an issue to Mills. For the occasion Mills was interviewed by Nick Currie, best known for his work as Momus, in a piece called "Getting Through the New Depression".


title: Mike Mills (director)

text: In 2019, he directed the short film "I Am Easy to Find" starring Alicia Vikander, which accompanied the album of the same name by The National.


title: Mike Mills (director)

text: Mills' latest directorial feature film starring Joaquin Phoenix, titled "C'mon C'mon", had its world premiere on 2 September 2021 at Telluride Film Festival.


title: Mike Mills (director)

text: Mills' mother died of brain cancer in 1999. Six months after she died, his father Paul came out as gay at the age of 75 and after 45 years of marriage. Five years later, his father died of cancer.


title: Mike Mills (director)

text: Mills is married to fellow artist and film director Miranda July, with whom he has a child, born in February 2012.


title: MoSCoW method

text: The MoSCoW method is a prioritization technique used in management, business analysis, project management, and software development to reach a common understanding with stakeholders on the importance they place on the delivery of each requirement; it is also known as "MoSCoW prioritization" or "MoSCoW analysis".


title: MoSCoW method

text: The term "MOSCOW" itself is an acronym derived from the first letter of each of four prioritization categories:


title: MoSCoW method

text: The interstitial "O"s are added to make the word pronounceable. While the "O"s are usually in lower-case to indicate that they do not stand for anything, the all-capitals "MOSCOW" is also used.


title: MoSCoW method

text: This prioritization method was developed by Dai Clegg in 1994 for use in rapid application development (RAD). It was first used extensively with the dynamic systems development method (DSDM) from 2002.


title: MoSCoW method

text: MoSCoW is often used with timeboxing, where a deadline is fixed so that the focus must be on the most important requirements, and is commonly used in agile software development approaches such as Scrum, rapid application development (RAD), and DSDM.


title: MoSCoW method

text: All requirements are important, however to deliver the greatest and most immediate business benefits early the requirements must be prioritized. Developers will initially try to deliver all the "Must have", "Should have" and "Could have" requirements but the "Should" and "Could" requirements will be the first to be removed if the delivery timescale looks threatened.


title: MoSCoW method

text: The plain English meaning of the prioritization categories has value in getting customers to better understand the impact of setting a priority, compared to alternatives like "High", "Medium" and "Low".


title: MoSCoW method

text: Sometimes W is used to mean "wish" (or "would"), i.e. still possible but unlikely to be included (and less likely than "could"). This is then distinguished from X for "excluded" for items which are explicitly not included.


title: MoSCoW method

text: In new product development, particularly those following agile software development approaches, there is always more to do than there is time or funding to permit (hence the need for prioritization).


title: MoSCoW method

text: For example, should a team have too many potential epics (i.e., high-level stories) for the next release of their product, they could use the "MoSCoW method" to select which epics are "Must have", which "Should have", and so on; the minimum viable product (or MVP) would be all those epics marked as "Must have". Oftentimes, a team will find that, even after identifying their MVP, they have too much work for their expected capacity. In such cases, the team could then use the "MoSCoW method" to select which features (or stories, if that is the subset of epics in their organisation) are "Must have", "Should have", and so on; the minimum marketable features (or MMF) would be all those marked as "Must have". If there is sufficient capacity after selecting the MVP or MMF, the team could then plan to include "Should have" and even "Could have" items too.


title: The Sunday Times

text: The Sunday Times is a British newspaper whose circulation makes it the largest in Britain's quality press market category. It was founded in 1821 as The New Observer. It is published by Times Newspapers Ltd, a subsidiary of News UK, which is owned by News Corp. Times Newspapers also publishes "The Times". The two papers were founded independently and have been under common ownership since 1966. They were bought by News International in 1981.


title: The Sunday Times

text: "The Sunday Times" has a circulation of just over 650,000, which exceeds that of its main rivals, including "The" "Sunday Telegraph" and "The" "Observer", combined. While some other national newspapers moved to a tabloid format in the early 2000s, "The Sunday Times" has retained the larger broadsheet format and has said that it would continue to do so. As of December 2019, it sells 75% more copies than its sister paper, "The Times", which is published from Monday to Saturday.


title: The Sunday Times

text: The paper began publication on 18 February 1821 as "The New Observer", but from 21 April its title was changed to the "Independent Observer". Its founder, Henry White, chose the name in an apparent attempt to take advantage of the success of the "Observer", which had been founded in 1791, although there was no connection between the two papers. On 20 October 1822 it was reborn as "The Sunday Times", although it had no relationship with "The Times". In January 1823, White sold the paper to Daniel Whittle Harvey, a radical politician.


title: The Sunday Times

text: Under its new owner, "The Sunday Times" notched up several firsts: a wood engraving it published of the coronation of Queen Victoria in 1838 was the largest illustration to have appeared in a British newspaper. In 1841, it became one of the first papers to serialise a novel: William Harrison Ainsworth's "Old St Paul's".


title: The Sunday Times

text: The paper was bought in 1887 by Alice Anne Cornwell who had made a fortune in mining in Australia and floating the Midas Mine Company of the London Stock Exchange. She bought the paper to promote her new company, The British and Australasian Mining Investment Company, and as a gift to her lover Frederick Stannard (‘Phil’) Robinson. Robinson was installed as editor and the two were later married in 1894.


title: The Sunday Times

text: She then sold it in 1893 to Frederick Beer, who already owned "Observer". Beer appointed his wife, Rachel Sassoon Beer, as editor. She was already editor of "Observer" – the first woman to run a national newspaper – and continued to edit both titles until 1901.


title: The Sunday Times

text: There was a further change of ownership in 1903, and then in 1915 the paper was bought by William Berry and his brother, Gomer Berry, later ennobled as Lord Camrose and Viscount Kemsley respectively. Under their ownership, "The Sunday Times" continued its reputation for innovation: on 23 November 1930, it became the first Sunday newspaper to publish a 40-page issue and on 21 January 1940, news replaced advertising on the front page.


title: The Sunday Times

text: In 1943, the Kemsley Newspapers Group was established, with "The Sunday Times" becoming its flagship paper. At this time, Kemsley was the largest newspaper group in Britain.


title: The Sunday Times

text: On 12 November 1945, Ian Fleming, who later created James Bond, joined the paper as foreign manager (foreign editor) and special writer. The following month, circulation reached 500,000. On 28 September 1958, the paper launched a separate Review section, becoming the first newspaper to publish two sections regularly.


title: The Sunday Times

text: In 1959, the Kemsley group was bought by Lord Thomson, and in October 1960 circulation reached one million for the first time. In another first, on 4 February 1962 the editor, Denis Hamilton, launched "The Sunday Times Magazine". (At the insistence of newsagents, worried at the impact on sales of standalone magazines, it was initially called the "colour section" and did not take the name "The Sunday Times Magazine" until 9 August 1964.) The cover picture of the first issue was of Jean Shrimpton wearing a Mary Quant outfit and was taken by David Bailey. The magazine got off to a slow start, but the advertising soon began to pick up, and, over time, other newspapers launched magazines of their own.


title: The Sunday Times

text: In 1963, the Insight investigative team was established under Clive Irving. On 27 September 1964, the "Business" section was launched, making "The Sunday Times" Britain's first regular three-section newspaper. In September 1966, Thomson bought "The Times", to form Times Newspapers Ltd (TNL). It was the first time both "The Sunday Times" and "The Times" had been brought under the same ownership.


title: The Sunday Times

text: Harold Evans, editor from 1967 until 1981, established "The Sunday Times" as a leading campaigning and investigative newspaper. On 19 May 1968, the paper published its first major campaigning report on the drug Thalidomide, which had been reported by the Australian doctor William McBride in "The Lancet" in 1961 as associated with birth defects, and quickly withdrawn. The newspaper published a four-page Insight investigation, entitled "The Thalidomide File", in the "Weekly Review" section. A compensation settlement for the UK victims was eventually reached with Distillers Company (now part of Diageo), which had distributed the drug in the UK.


title: The Sunday Times

text: TNL was plagued by a series of industrial disputes at its plant at Gray's Inn Road in London, with the print unions resisting attempts to replace the old-fashioned hot-metal and labour-intensive Linotype method with technology that would allow the papers to be composed digitally. Thomson offered to invest millions of pounds to buy out obstructive practices and overmanning, but the unions rejected every proposal. As a result, publication of "The Sunday Times" and other titles in the group was suspended in November 1978. It did not resume until November 1979.


title: The Sunday Times

text: Although journalists at "The Times" had been on full pay during the suspension, they went on strike demanding more money after production was resumed. Kenneth Thomson, the head of the company, felt betrayed and decided to sell. Evans tried to organise a management buyout of "The Sunday Times", but Thomson decided instead to sell to Rupert Murdoch, who he thought had a better chance of dealing with the trade unions.


title: The Sunday Times

text: Murdoch's News International acquired the group in February 1981. Murdoch, an Australian who in 1985 became a naturalised American citizen, already owned "The Sun" and the "News of the World", but the Conservative government decided not to refer the deal to the Monopolies and Mergers Commission, citing a clause in the Fair Trading Act that exempted uneconomic businesses from referral. The Thomson Corporation had threatened to close the papers down if they were not taken over by someone else within an allotted time, and it was feared that any legal delay to Murdoch's takeover might lead to the two titles' demise. In return, Murdoch provided legally binding guarantees to preserve the titles' editorial independence.


title: The Sunday Times

text: Evans was appointed editor of "The Times" in February 1981 and was replaced at "The Sunday Times" by Frank Giles. In 1983, the newspaper bought the serialisation rights to publish the faked "Hitler Diaries", thinking them to be genuine after they were authenticated by the own newspaper's own independent director, Hugh Trevor-Roper, the historian and author of "The Last Days of Hitler".


title: The Sunday Times

text: Under Andrew Neil, editor from 1983 until 1994, "The Sunday Times" took a strongly Thatcherite slant that contrasted with the traditional paternalistic conservatism expounded by Peregrine Worsthorne at the rival "Sunday Telegraph". It also built on its reputation for investigations. Its scoops included the revelation in 1986 that Israel had manufactured more than 100 nuclear warheads and the publication in 1992 of extracts from Andrew Morton's book, "Diana: Her True Story in Her Own Words". In the early 1990s, the paper courted controversy with a series of articles in which it rejected the role of HIV in causing AIDS.


title: The Sunday Times

text: In January 1986, after the announcement of a strike by print workers, production of "The Sunday Times", along with other newspapers in the group, was shifted to a new plant in Wapping, and the strikers were dismissed. The plant, which allowed journalists to input copy directly, was activated with the help of the Electrical, Electronic, Telecommunications and Plumbing Union (EETPU). The print unions posted pickets and organised demonstrations outside the new plant to try to dissuade journalists and others from working there, in what became known as the Wapping Dispute. The demonstrations sometimes turned violent. The protest ended in failure in February 1987.


title: The Sunday Times

text: During Neil's editorship, a number of new sections were added: the annual "The Sunday Times" Rich List and the Funday Times, in 1989, (the latter stopped appearing in print and was relaunched as a standalone website in March 2006, but was later closed); Style & Travel, News Review and Arts in 1990, and Culture in 1992. In September 1994, Style and Travel became two separate sections.


title: The Sunday Times

text: During Neil's time as editor, "The Sunday Times" backed a campaign to prove that HIV was not a cause of AIDS. In 1990, "The Sunday Times" serialized a book by an American conservative who rejected the scientific consensus on the causes of AIDS and argued that AIDS could not spread to heterosexuals. Articles and editorials in "The Sunday Times" cast doubt on the scientific consensus, described HIV as a "politically correct virus" about which there was a "conspiracy of silence," disputed that AIDS was spreading in Africa, claimed that tests for HIV were invalid, described the HIV/AIDS treatment drug AZT as harmful, and characterized the WHO as an "Empire-building AIDS [organisation]." The pseudoscientific coverage of HIV/AIDS in "the Sunday Times" led the scientific journal "Nature" to monitor the newspaper's coverage and to publish letters rebutting "Sunday Times" articles which "the Sunday Times" refused to publish. In response to this, "the Sunday Times" published an article headlined "AIDS - why we won’t be silenced", which claimed that "Nature" engaged in censorship and "sinister intent". In his 1996 book, "Full Disclosure", Neil wrote that the HIV/AIDS denialism "deserved publication to encourage debate." That same year, he wrote that "the Sunday Times" had been vindicated in its coverage, "The Sunday Times was one of a handful of newspapers, perhaps the most prominent, which argued that heterosexual Aids was a myth. The figures are now in and this newspaper stands totally vindicated... The history of Aids is one of the great scandals of our time. I do not blame doctors and the Aids lobby for warning that everybody might be at risk in the early days, when ignorance was rife and reliable evidence scant." He criticized the "AIDS establishment" and said "Aids had become an industry, a job-creation scheme for the caring classes."


title: The Sunday Times

text: John Witherow, who became editor at the end of 1994 (after several months as acting editor), continued the newspaper's expansion. A website was launched in 1996 and new print sections added: Home in 2001, and Driving in 2002, which in 2006 was renamed InGear. (It reverted to the name Driving from 7 October 2012, to coincide with the launch of a new standalone website, Sunday Times Driving.) Technology coverage was expanded in 2000 with the weekly colour magazine Doors, and in 2003 The Month, an editorial section presented as an interactive CD-Rom. Magazine partworks were regular additions, among them 1000 Makers of Music, published over six weeks in 1997.


title: The Sunday Times

text: John Witherow oversaw a rise in circulation to 1.3 million and reconfirmed "The Sunday Times's" reputation for publishing hard-hitting news stories – such as Cash for Questions in 1994 and Cash for Honours in 2006, and revelations of corruption at Fifa in 2010. The newspaper's foreign coverage has been especially strong, and its reporters, Marie Colvin, Jon Swain, Hala Jaber, Mark Franchetti and Christina Lamb have dominated the Foreign Reporter of the Year category at the British Press Awards since 2000. Colvin, who worked for the paper from 1985, was killed in February 2012 by Syrian forces while covering the siege of Homs during that country's civil war.


title: The Sunday Times

text: In common with other newspapers, "The Sunday Times" has been hit by a fall in circulation, which has declined from a peak of 1.3 million to just over 710,000. It has a number of digital-only subscribers, which numbered 99,017 by January 2019.


title: The Sunday Times

text: During January 2013, Martin Ivens became 'acting' editor of "The Sunday Times" in succession to John Witherow, who became the 'acting' editor of "The Times" at the same time. The independent directors rejected a permanent position for Ivens as editor to avoid any possible merger of "The Sunday Times" and daily "Times" titles.


title: The Sunday Times

text: "The Sunday Times" has its own website. It previously shared an online presence with "The Times", but in May 2010 they both launched their own sites to reflect their distinct brand identities. Since July 2010, the sites are charging for access.


title: The Sunday Times

text: An iPad edition was launched in December 2010, and an Android version in August 2011. Since July 2012, the digital version of the paper has been available on Apple's Newsstand platform, allowing automated downloading of the news section. With over 500 MB of content every week, it is the biggest newspaper app in the world.


title: The Sunday Times

text: "The Sunday Times" iPad app was named newspaper app of the year at the 2011 Newspaper Awards and has twice been ranked best newspaper or magazine app in the world by iMonitor. Various subscription packages exist, giving access to both the print and digital versions of the paper.


title: The Sunday Times

text: On 2 October 2012, "The Sunday Times" launched Sunday Times Driving, a separate classified advertising site for premium vehicles that also includes editorial content from the newspaper as well as specially commissioned articles. It can be accessed without cost.


title: The Sunday Times

text: This 164-page monthly magazine is sold separately from the newspaper and is Britain's best-selling travel magazine. The first issue of "The Sunday Times Travel Magazine" was in 2003, and it includes news, features and insider guides.


title: The Sunday Times

text: In July 2011, "The Sunday Times" was implicated in the wider News International phone hacking scandal, which primarily involved the "News of the World", a Murdoch tabloid newspaper published in the UK from 1843 to 2011. Former British prime minister Gordon Brown accused "The Sunday Times" of employing "known criminals" to impersonate him and obtain his private financial records. Brown's bank reported that an investigator employed by "The Sunday Times" repeatedly impersonated Brown to gain access to his bank account records. "The Sunday Times" vigorously denied these accusations and said that the story was in the public interest and that it had followed the Press Complaints Commission code on using subterfuge.


title: The Sunday Times

text: The Irish edition of "The Sunday Times" was launched on a small scale on 1993 with just two staff: Alan Ruddock and John Burns (who started as financial correspondent for the newspaper and is at present acting associate editor). It used the slogan "The English just don't get it". It is now the third biggest-selling newspaper in Ireland measured in terms of full-price cover sales (Source: ABC Jan–June 2012). Circulation had grown steadily to over 127,000 in the two decades before 2012, but has declined since and currently stands at 60,352 (Jan to Jun 2018).


title: The Sunday Times

text: The paper is heavily editionalised, with extensive Irish coverage of politics, general news, business, personal finance, sport, culture and lifestyle. The office employs 25 people. The paper also has a number of well-known freelance columnists including Brenda Power, Liam Fay, Matt Cooper, Damien Kiberd, Jill Kerby and Stephen Price. However, it ended collaboration with Kevin Myers after he had published a controversial column. The Irish edition has had four editors since it was set up: Alan Ruddock from 1993 until 1996, Rory Godson from 1996 until 2000, Fiona McHugh from 2000 to 2005, and from 2005 until 2020 Frank Fitzgibbon. John Burns is acting editor of the Irish Edition from 2020.


title: The Sunday Times

text: For more than 20 years the paper has published a separate Scottish edition, which has been edited since January 2012 by Jason Allardyce. While most of the articles that run in the English edition appear in the Scottish edition, its staff also produces about a dozen Scottish news stories, including a front-page article, most weeks. The edition also contains a weekly "Scottish Focus" feature and Scottish commentary, and covers Scottish sport in addition to providing Scottish television schedules. The Scottish issue is the biggest-selling quality newspaper in the market, outselling both "Scotland on Sunday" and the "Sunday Herald".


title: Astrobiology

text: Astrobiology, and the related field of exobiology, is an interdisciplinary scientific field that studies the origins, early evolution, distribution, and future of life in the universe. Astrobiology is the multidisciplinary field that investigates the deterministic conditions and contingent events with which life arises, distributes, and evolves in the universe.


title: Astrobiology

text: Astrobiology makes use of molecular biology, biophysics, biochemistry, chemistry, astronomy, physical cosmology, exoplanetology, geology, paleontology, and ichnology to investigate the possibility of life on other worlds and help recognize biospheres that might be different from that on Earth. The origin and early evolution of life is an inseparable part of the discipline of astrobiology. Astrobiology concerns itself with interpretation of existing scientific data, and although speculation is entertained to give context, astrobiology concerns itself primarily with hypotheses that fit firmly into existing scientific theories.


title: Astrobiology

text: This interdisciplinary field encompasses research on the origin of planetary systems, origins of organic compounds in space, rock-water-carbon interactions, abiogenesis on Earth, planetary habitability, research on biosignatures for life detection, and studies on the potential for life to adapt to challenges on Earth and in outer space.


title: Astrobiology

text: Biochemistry may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the Universe was only 10–17 million years old. According to the panspermia hypothesis, microscopic life—distributed by meteoroids, asteroids and other small Solar System bodies—may exist throughout the universe. According to research published in August 2015, very large galaxies may be more favorable to the creation and development of habitable planets than such smaller galaxies as the Milky Way. Nonetheless, Earth is the only place in the universe known to harbor life. Estimates of habitable zones around other stars, sometimes referred to as "Goldilocks zones", along with the discovery of thousands of extrasolar planets and new insights into extreme habitats here on Earth, suggest that there may be many more habitable places in the universe than considered possible until very recently.


title: Astrobiology

text: Current studies on the planet Mars by the "Curiosity" and "Perseverance" rovers are searching for evidence of ancient life as well as plains related to ancient rivers or lakes that may have been habitable. The search for evidence of habitability, taphonomy (related to fossils), and organic molecules on the planet Mars is now a primary NASA and ESA objective.


title: Astrobiology

text: Even if extraterrestrial life is never discovered, the interdisciplinary nature of astrobiology, and the cosmic and evolutionary perspectives engendered by it, may still result in a range of benefits here on Earth.


title: Astrobiology

text: The term was first proposed by the Russian (Soviet) astronomer Gavriil Tikhov in 1953. "Astrobiology" is etymologically derived from the Greek , "astron", "constellation, star"; , "bios", "life"; and , "-logia", "study". The synonyms of astrobiology are diverse; however, the synonyms were structured in relation to the most important sciences implied in its development: astronomy and biology. A close synonym is "exobiology" from the Greek , "external"; Βίος, "bios", "life"; and λογία, -logia, "study". The term exobiology was coined by molecular biologist and Nobel Prize winner Joshua Lederberg. Exobiology is considered to have a narrow scope limited to search of life external to Earth, whereas subject area of astrobiology is wider and investigates the link between life and the universe, which includes the search for extraterrestrial life, but also includes the study of life on Earth, its origin, evolution and limits.


title: Astrobiology

text: Another term used in the past is xenobiology, ("biology of the foreigners") a word used in 1954 by science fiction writer Robert Heinlein in his work "The Star Beast". The term xenobiology is now used in a more specialized sense, to mean "biology based on foreign chemistry", whether of extraterrestrial or terrestrial (possibly synthetic) origin. Since alternate chemistry analogs to some life-processes have been created in the laboratory, xenobiology is now considered as an extant subject.


title: Astrobiology

text: While it is an emerging and developing field, the question of whether life exists elsewhere in the universe is a verifiable hypothesis and thus a valid line of scientific inquiry. Though once considered outside the mainstream of scientific inquiry, astrobiology has become a formalized field of study. Planetary scientist David Grinspoon calls astrobiology a field of natural philosophy, grounding speculation on the unknown, in known scientific theory. NASA's interest in exobiology first began with the development of the U.S. Space Program. In 1959, NASA funded its first exobiology project, and in 1960, NASA founded an Exobiology Program, which is now one of four main elements of NASA's current Astrobiology Program. In 1971, NASA funded the search for extraterrestrial intelligence (SETI) to search radio frequencies of the electromagnetic spectrum for interstellar communications transmitted by extraterrestrial life outside the Solar System. NASA's Viking missions to Mars, launched in 1976, included three biology experiments designed to look for metabolism of present life on Mars.


title: Astrobiology

text: Advancements in the fields of astrobiology, observational astronomy and discovery of large varieties of extremophiles with extraordinary capability to thrive in the harshest environments on Earth, have led to speculation that life may possibly be thriving on many of the extraterrestrial bodies in the universe. A particular focus of current astrobiology research is the search for life on Mars due to this planet's proximity to Earth and geological history. There is a growing body of evidence to suggest that Mars has previously had a considerable amount of water on its surface, water being considered an essential precursor to the development of carbon-based life.


title: Astrobiology

text: Missions specifically designed to search for current life on Mars were the Viking program and Beagle 2 probes. The Viking results were inconclusive, and Beagle 2 failed minutes after landing. A future mission with a strong astrobiology role would have been the Jupiter Icy Moons Orbiter, designed to study the frozen moons of Jupiter—some of which may have liquid water—had it not been cancelled. In late 2008, the Phoenix lander probed the environment for past and present planetary habitability of microbial life on Mars, and researched the history of water there.


title: Astrobiology

text: The European Space Agency's astrobiology roadmap from 2016, identified five main research topics, and specifies several key scientific objectives for each topic. The five research topics are: 1) Origin and evolution of planetary systems; 2) Origins of organic compounds in space; 3) Rock-water-carbon interactions, organic synthesis on Earth, and steps to life; 4) Life and habitability; 5) Biosignatures as facilitating life detection.


title: Astrobiology

text: In November 2011, NASA launched the Mars Science Laboratory mission carrying the "Curiosity" rover, which landed on Mars at Gale Crater in August 2012. The "Curiosity" rover is currently probing the environment for past and present planetary habitability of microbial life on Mars. On 9 December 2013, NASA reported that, based on evidence from "Curiosity" studying Aeolis Palus, Gale Crater contained an ancient freshwater lake which could have been a hospitable environment for microbial life.


title: Astrobiology

text: The European Space Agency is currently collaborating with the Russian Federal Space Agency (Roscosmos) and developing the ExoMars astrobiology rover, which was scheduled to be launched in July 2020, but was postponed to 2022. Meanwhile, NASA launched the Mars 2020 astrobiology rover and sample cacher for a later return to Earth.


title: Astrobiology

text: When looking for life on other planets like Earth, some simplifying assumptions are useful to reduce the size of the task of the astrobiologist. One is the informed assumption that the vast majority of life forms in our galaxy are based on carbon chemistries, as are all life forms on Earth. Carbon is well known for the unusually wide variety of molecules that can be formed around it. Carbon is the fourth most abundant element in the universe and the energy required to make or break a bond is at just the appropriate level for building molecules which are not only stable, but also reactive. The fact that carbon atoms bond readily to other carbon atoms allows for the building of extremely long and complex molecules.


title: Astrobiology

text: The presence of liquid water is an assumed requirement, as it is a common molecule and provides an excellent environment for the formation of complicated carbon-based molecules that could eventually lead to the emergence of life.


title: Astrobiology

text: Some researchers posit environments of water-ammonia mixtures as possible solvents for hypothetical types of biochemistry.


title: Astrobiology

text: A third assumption is to focus on planets orbiting Sun-like stars for increased probabilities of planetary habitability. Very large stars have relatively short lifetimes, meaning that life might not have time to emerge on planets orbiting them. Very small stars provide so little heat and warmth that only planets in very close orbits around them would not be frozen solid, and in such close orbits these planets would be tidally "locked" to the star. The long lifetimes of red dwarfs could allow the development of habitable environments on planets with thick atmospheres. This is significant, as red dwarfs are extremely common. (See Habitability of red dwarf systems).


title: Astrobiology

text: Since Earth is the only planet known to harbor life, there is no evident way to know if any of these simplifying assumptions are correct.


title: Astrobiology

text: Research on communication with extraterrestrial intelligence (CETI) focuses on composing and deciphering messages that could theoretically be understood by another technological civilization. Communication attempts by humans have included broadcasting mathematical languages, pictorial systems such as the Arecibo message and computational approaches to detecting and deciphering 'natural' language communication. The SETI program, for example, uses both radio telescopes and optical telescopes to search for deliberate signals from an extraterrestrial intelligence.


title: Astrobiology

text: While some high-profile scientists, such as Carl Sagan, have advocated the transmission of messages, scientist Stephen Hawking warned against it, suggesting that aliens might simply raid Earth for its resources and then move on.


title: Astrobiology

text: Most astronomy-related astrobiology research falls into the category of extrasolar planet (exoplanet) detection, the hypothesis being that if life arose on Earth, then it could also arise on other planets with similar characteristics. To that end, a number of instruments designed to detect Earth-sized exoplanets have been considered, most notably NASA's Terrestrial Planet Finder (TPF) and ESA's Darwin programs, both of which have been cancelled. NASA launched the "Kepler" mission in March 2009, and the French Space Agency launched the COROT space mission in 2006. There are also several less ambitious ground-based efforts underway.


title: Astrobiology

text: The goal of these missions is not only to detect Earth-sized planets but also to directly detect light from the planet so that it may be studied spectroscopically. By examining planetary spectra, it would be possible to determine the basic composition of an extrasolar planet's atmosphere and/or surface. Given this knowledge, it may be possible to assess the likelihood of life being found on that planet. A NASA research group, the Virtual Planet Laboratory, is using computer modeling to generate a wide variety of virtual planets to see what they would look like if viewed by TPF or Darwin. It is hoped that once these missions come online, their spectra can be cross-checked with these virtual planetary spectra for features that might indicate the presence of life.


title: Astrobiology

text: An estimate for the number of planets with intelligent "communicative" extraterrestrial life can be gleaned from the Drake equation, essentially an equation expressing the probability of intelligent life as the product of factors such as the fraction of planets that might be habitable and the fraction of planets on which life might arise:


title: Astrobiology

text: However, whilst the rationale behind the equation is sound, it is unlikely that the equation will be constrained to reasonable limits of error any time soon. The problem with the formula is that it is not used to generate or support hypotheses because it contains factors that can never be verified. The first term, R*, number of stars, is generally constrained within a few orders of magnitude. The second and third terms, "f", stars with planets and "f", planets with habitable conditions, are being evaluated for the star's neighborhood. Drake originally formulated the equation merely as an agenda for discussion at the Green Bank conference, but some applications of the formula had been taken literally and related to simplistic or pseudoscientific arguments. Another associated topic is the Fermi paradox, which suggests that if intelligent life is common in the universe, then there should be obvious signs of it.


title: Astrobiology

text: Another active research area in astrobiology is planetary system formation. It has been suggested that the peculiarities of the Solar System (for example, the presence of Jupiter as a protective shield) may have greatly increased the probability of intelligent life arising on our planet.


title: Astrobiology

text: Biology cannot state that a process or phenomenon, by being mathematically possible, has to exist forcibly in an extraterrestrial body. Biologists specify what is speculative and what is not. The discovery of extremophiles, organisms able to survive in extreme environments, became a core research element for astrobiologists, as they are important to understand four areas in the limits of life in planetary context: the potential for panspermia, forward contamination due to human exploration ventures, planetary colonization by humans, and the exploration of extinct and extant extraterrestrial life.


title: Astrobiology

text: Until the 1970s, life was thought to be entirely dependent on energy from the Sun. Plants on Earth's surface capture energy from sunlight to photosynthesize sugars from carbon dioxide and water, releasing oxygen in the process that is then consumed by oxygen-respiring organisms, passing their energy up the food chain. Even life in the ocean depths, where sunlight cannot reach, was thought to obtain its nourishment either from consuming organic detritus rained down from the surface waters or from eating animals that did. The world's ability to support life was thought to depend on its access to sunlight. However, in 1977, during an exploratory dive to the Galapagos Rift in the deep-sea exploration submersible "Alvin", scientists discovered colonies of giant tube worms, clams, crustaceans, mussels, and other assorted creatures clustered around undersea volcanic features known as black smokers. These creatures thrive despite having no access to sunlight, and it was soon discovered that they comprise an entirely independent ecosystem. Although most of these multicellular lifeforms need dissolved oxygen (produced by oxygenic photosynthesis) for their aerobic cellular respiration and thus are not completely independent from sunlight by themselves, the basis for their food chain is a form of bacterium that derives its energy from oxidization of reactive chemicals, such as hydrogen or hydrogen sulfide, that bubble up from the Earth's interior. Other lifeforms entirely decoupled from the energy from sunlight are green sulfur bacteria which are capturing geothermal light for anoxygenic photosynthesis or bacteria running chemolithoautotrophy based on the radioactive decay of uranium. This chemosynthesis revolutionized the study of biology and astrobiology by revealing that life need not be sun-dependent; it only requires water and an energy gradient in order to exist.


title: Astrobiology

text: Biologists have found extremophiles that thrive in ice, boiling water, acid, alkali, the water core of nuclear reactors, salt crystals, toxic waste and in a range of other extreme habitats that were previously thought to be inhospitable for life. This opened up a new avenue in astrobiology by massively expanding the number of possible extraterrestrial habitats. Characterization of these organisms, their environments and their evolutionary pathways, is considered a crucial component to understanding how life might evolve elsewhere in the universe. For example, some organisms able to withstand exposure to the vacuum and radiation of outer space include the lichen fungi "Rhizocarpon geographicum" and "Xanthoria elegans", the bacterium "Bacillus safensis", "Deinococcus radiodurans", "Bacillus subtilis", yeast "Saccharomyces cerevisiae", seeds from "Arabidopsis thaliana" ('mouse-ear cress'), as well as the invertebrate animal Tardigrade. While tardigrades are not considered true extremophiles, they are considered extremotolerant microorganisms that have contributed to the field of astrobiology. Their extreme radiation tolerance and presence of DNA protection proteins may provide answers as to whether life can survive away from the protection of the Earth's atmosphere.


title: Astrobiology

text: Jupiter's moon, Europa, and Saturn's moon, Enceladus, are now considered the most likely locations for extant extraterrestrial life in the Solar System due to their subsurface water oceans where radiogenic and tidal heating enables liquid water to exist.


title: Astrobiology

text: The origin of life, known as abiogenesis, distinct from the evolution of life, is another ongoing field of research. Oparin and Haldane postulated that the conditions on the early Earth were conducive to the formation of organic compounds from inorganic elements and thus to the formation of many of the chemicals common to all forms of life we see today. The study of this process, known as prebiotic chemistry, has made some progress, but it is still unclear whether or not life could have formed in such a manner on Earth. The alternative hypothesis of panspermia is that the first elements of life may have formed on another planet with even more favorable conditions (or even in interstellar space, asteroids, etc.) and then have been carried over to Earth.


title: Astrobiology

text: The cosmic dust permeating the universe contains complex organic compounds ("amorphous organic solids with a mixed aromatic-aliphatic structure") that could be created naturally, and rapidly, by stars. Further, a scientist suggested that these compounds may have been related to the development of life on Earth and said that, "If this is the case, life on Earth may have had an easier time getting started as these organics can serve as basic ingredients for life."


title: Astrobiology

text: More than 20% of the carbon in the universe may be associated with polycyclic aromatic hydrocarbons (PAHs), possible starting materials for the formation of life. PAHs seem to have been formed shortly after the Big Bang, are widespread throughout the universe, and are associated with new stars and exoplanets. PAHs are subjected to interstellar medium conditions and are transformed through hydrogenation, oxygenation and hydroxylation, to more complex organics—"a step along the path toward amino acids and nucleotides, the raw materials of proteins and DNA, respectively".


title: Astrobiology

text: In October 2020, astronomers proposed the idea of detecting life on distant planets by studying the shadows of trees at certain times of the day to find patterns that could be detected through observation of exoplanets.


title: Astrobiology

text: Astroecology concerns the interactions of life with space environments and resources, in planets, asteroids and comets. On a larger scale, astroecology concerns resources for life about stars in the galaxy through the cosmological future. Astroecology attempts to quantify future life in space, addressing this area of astrobiology.


title: Astrobiology

text: Experimental astroecology investigates resources in planetary soils, using actual space materials in meteorites. The results suggest that Martian and carbonaceous chondrite materials can support bacteria, algae and plant (asparagus, potato) cultures, with high soil fertilities. The results support that life could have survived in early aqueous asteroids and on similar materials imported to Earth by dust, comets and meteorites, and that such asteroid materials can be used as soil for future space colonies.


title: Astrobiology

text: On the largest scale, cosmoecology concerns life in the universe over cosmological times. The main sources of energy may be red giant stars and white and red dwarf stars, sustaining life for 10 years. Astroecologists suggest that their mathematical models may quantify the potential amounts of future life in space, allowing a comparable expansion in biodiversity, potentially leading to diverse intelligent life forms.


title: Astrobiology

text: Astrogeology is a planetary science discipline concerned with the geology of celestial bodies such as the planets and their moons, asteroids, comets, and meteorites. The information gathered by this discipline allows the measure of a planet's or a natural satellite's potential to develop and sustain life, or planetary habitability.


title: Astrobiology

text: An additional discipline of astrogeology is geochemistry, which involves study of the chemical composition of the Earth and other planets, chemical processes and reactions that govern the composition of rocks and soils, the cycles of matter and energy and their interaction with the hydrosphere and the atmosphere of the planet. Specializations include cosmochemistry, biochemistry and organic geochemistry.


title: Astrobiology

text: The fossil record provides the oldest known evidence for life on Earth. By examining the fossil evidence, paleontologists are able to better understand the types of organisms that arose on the early Earth. Some regions on Earth, such as the Pilbara in Western Australia and the McMurdo Dry Valleys of Antarctica, are also considered to be geological analogs to regions of Mars, and as such, might be able to provide clues on how to search for past life on Mars.


title: Astrobiology

text: The various organic functional groups, composed of hydrogen, oxygen, nitrogen, phosphorus, sulfur, and a host of metals, such as iron, magnesium, and zinc, provide the enormous diversity of chemical reactions necessarily catalyzed by a living organism. Silicon, in contrast, interacts with only a few other atoms, and the large silicon molecules are monotonous compared with the combinatorial universe of organic macromolecules. Indeed, it seems likely that the basic building blocks of life anywhere will be similar to those on Earth, in the generality if not in the detail. Although terrestrial life and life that might arise independently of Earth are expected to use many similar, if not identical, building blocks, they also are expected to have some biochemical qualities that are unique. If life has had a comparable impact elsewhere in the Solar System, the relative abundances of chemicals key for its survival—whatever they may be—could betray its presence. Whatever extraterrestrial life may be, its tendency to chemically alter its environment might just give it away.


title: Astrobiology

text: People have long speculated about the possibility of life in settings other than Earth, however, speculation on the nature of life elsewhere often has paid little heed to constraints imposed by the nature of biochemistry. The likelihood that life throughout the universe is probably carbon-based is suggested by the fact that carbon is one of the most abundant of the higher elements. Only two of the natural atoms, carbon and silicon, are known to serve as the backbones of molecules sufficiently large to carry biological information. As the structural basis for life, one of carbon's important features is that, unlike silicon, it can readily engage in the formation of chemical bonds with many other atoms, thereby allowing for the chemical versatility required to conduct the reactions of biological metabolism and propagation.


title: Astrobiology

text: Discussion on where in the Solar System life might occur was limited historically by the understanding that life relies ultimately on light and warmth from the Sun and, therefore, is restricted to the surfaces of planets. The four most likely candidates for life in the Solar System are the planet Mars, the Jovian moon Europa, and Saturn's moons Titan and Enceladus.


title: Astrobiology

text: Mars, Enceladus and Europa are considered likely candidates in the search for life primarily because they may have underground liquid water, a molecule essential for life as we know it for its use as a solvent in cells. Water on Mars is found frozen in its polar ice caps, and newly carved gullies recently observed on Mars suggest that liquid water may exist, at least transiently, on the planet's surface. At the Martian low temperatures and low pressure, liquid water is likely to be highly saline. As for Europa and Enceladus, large global oceans of liquid water exist beneath these moons' icy outer crusts. This water may be warmed to a liquid state by volcanic vents on the ocean floor, but the primary source of heat is probably tidal heating. On 11 December 2013, NASA reported the detection of "clay-like minerals" (specifically, phyllosilicates), often associated with organic materials, on the icy crust of Europa. The presence of the minerals may have been the result of a collision with an asteroid or comet according to the scientists. Additionally, on 27 June 2018, astronomers reported the detection of complex macromolecular organics on Enceladus and, according to NASA scientists in May 2011, "is emerging as the most habitable spot beyond Earth in the Solar System for life as we know it".


title: Astrobiology

text: Another planetary body that could potentially sustain extraterrestrial life is Saturn's largest moon, Titan. Titan has been described as having conditions similar to those of early Earth. On its surface, scientists have discovered the first liquid lakes outside Earth, but these lakes seem to be composed of ethane and/or methane, not water. Some scientists think it possible that these liquid hydrocarbons might take the place of water in living cells different from those on Earth. After Cassini data were studied, it was reported in March 2008 that Titan may also have an underground ocean composed of liquid water and ammonia.


title: Astrobiology

text: Phosphine has been detected in the atmosphere of the planet Venus. There are no known abiotic processes on the planet that could cause its presence. Given that Venus has the hottest surface temperature of any planet in the solar system, Venusian life, if it exists, is most likely limited to extremophile microorganisms that float in the planet's upper atmosphere, where conditions are almost Earth-like.


title: Astrobiology

text: Measuring the ratio of hydrogen and methane levels on Mars may help determine the likelihood of life on Mars. According to the scientists, "...low H/CH ratios (less than approximately 40) indicate that life is likely present and active." Other scientists have recently reported methods of detecting hydrogen and methane in extraterrestrial atmospheres.


title: Astrobiology

text: Complex organic compounds of life, including uracil, cytosine and thymine, have been formed in a laboratory under outer space conditions, using starting chemicals such as pyrimidine, found in meteorites. Pyrimidine, like polycyclic aromatic hydrocarbons (PAHs), is the most carbon-rich chemical found in the universe.


title: Astrobiology

text: The Rare Earth hypothesis postulates that multicellular life forms found on Earth may actually be more of a rarity than scientists assume. According to this hypothesis, life on Earth (and more, multi-cellular life) is possible because of a conjunction of the right circumstances (galaxy and location within it, solar system, star, orbit, planetary size, atmosphere, etc.); and the chance for all those circumstances to repeat elsewhere may be rare. It provides a possible answer to the Fermi paradox which suggests, "If extraterrestrial aliens are common, why aren't they obvious?" It is apparently in opposition to the principle of mediocrity, assumed by famed astronomers Frank Drake, Carl Sagan, and others. The Principle of Mediocrity suggests that life on Earth is not exceptional, and it is more than likely to be found on innumerable other worlds.


title: Astrobiology

text: The systematic search for possible life outside Earth is a valid multidisciplinary scientific endeavor. However, hypotheses and predictions as to its existence and origin vary widely, and at the present, the development of hypotheses firmly grounded on science may be considered astrobiology's most concrete practical application. It has been proposed that viruses are likely to be encountered on other life-bearing planets, and may be present even if there are no biological cells.


title: Astrobiology

text: , no evidence of extraterrestrial life has been identified. Examination of the Allan Hills 84001 meteorite, which was recovered in Antarctica in 1984 and originated from Mars, is thought by David McKay, as well as few other scientists, to contain microfossils of extraterrestrial origin; this interpretation is controversial.


title: Astrobiology

text: Yamato 000593, the second largest meteorite from Mars, was found on Earth in 2000. At a microscopic level, spheres are found in the meteorite that are rich in carbon compared to surrounding areas that lack such spheres. The carbon-rich spheres may have been formed by biotic activity according to some NASA scientists.


title: Astrobiology

text: On 5 March 2011, Richard B. Hoover, a scientist with the Marshall Space Flight Center, speculated on the finding of alleged microfossils similar to cyanobacteria in CI1 carbonaceous meteorites in the fringe "Journal of Cosmology", a story widely reported on by mainstream media. However, NASA formally distanced itself from Hoover's claim. According to American astrophysicist Neil deGrasse Tyson: "At the moment, life on Earth is the only known life in the universe, but there are compelling arguments to suggest we are not alone."


title: Astrobiology

text: On 17 March 2013, researchers reported that microbial life forms thrive in the Mariana Trench, the deepest spot on the Earth. Other researchers reported that microbes thrive inside rocks up to below the sea floor under of ocean off the coast of the northwestern United States. According to one of the researchers, "You can find microbes everywhere—they're extremely adaptable to conditions, and survive wherever they are." Evidence of perchlorates have been found throughout the solar system, and specifically on Mars. Dr. Kennda Lynch discovered the first known instance of perchlorates and perchlorates-reducing microbes in a paleolake in Pilot Valley, Utah. These finds expand the potential habitability of certain niches of other planets.


title: Astrobiology

text: In 2004, the spectral signature of methane () was detected in the Martian atmosphere by both Earth-based telescopes as well as by the "Mars Express" orbiter. Because of solar radiation and cosmic radiation, methane is predicted to disappear from the Martian atmosphere within several years, so the gas must be actively replenished in order to maintain the present concentration. On 7 June 2018, NASA announced a cyclical seasonal variation in atmospheric methane, which may be produced by geological or biological sources. The European ExoMars Trace Gas Orbiter is currently measuring and mapping the atmospheric methane.


title: Astrobiology

text: It is possible that some exoplanets may have moons with solid surfaces or liquid oceans that are hospitable. Most of the planets so far discovered outside the Solar System are hot gas giants thought to be inhospitable to life, so it is not yet known whether the Solar System, with a warm, rocky, metal-rich inner planet such as Earth, is of an aberrant composition. Improved detection methods and increased observation time will undoubtedly discover more planetary systems, and possibly some more like ours. For example, NASA's Kepler Mission seeks to discover Earth-sized planets around other stars by measuring minute changes in the star's light curve as the planet passes between the star and the spacecraft. Progress in infrared astronomy and submillimeter astronomy has revealed the constituents of other star systems.


title: Astrobiology

text: Efforts to answer questions such as the abundance of potentially habitable planets in habitable zones and chemical precursors have had much success. Numerous extrasolar planets have been detected using the wobble method and transit method, showing that planets around other stars are more numerous than previously postulated. The first Earth-sized extrasolar planet to be discovered within its star's habitable zone is Gliese 581 c.


title: Astrobiology

text: Studying extremophiles is useful for understanding the possible origin of life on Earth as well as for finding the most likely candidates for future colonization of other planets. The aim is to detect those organisms that are able to survive space travel conditions and to maintain the proliferating capacity. The best candidates are extremophiles, since they have adapted to survive in different kind of extreme conditions on earth. During the course of evolution, extremophiles have developed various strategies to survive the different stress conditions of different extreme environments. These stress responses could also allow them to survive in harsh space conditions, although evolution also puts some restrictions on their use as analogues to extraterrestrial life.


title: Astrobiology

text: The thermophilic species "Geobacillus thermantarcticus" is an example of a microorganism that could in principle survive a period of space travel. It is a spore-forming bacterium. The formation of spores allows for it to survive extreme environments while still being able to restart cellular growth. It is capable of effectively protecting its DNA, membrane and proteins integrity in different extreme conditions (desiccation, temperatures up to -196 °C, UVC and C-ray radiation...). It is also able to repair the damage produced by space environment.


title: Astrobiology

text: Some locations on Earth are particularly well-suited for astrobiological studies of extremophiles. For example, Valeria Souza and colleagues proposed that the Cuatro Ciénegas basin in Coahuila, Mexico, could serve as an "astrobiological Precambrian park" due to the similarity of some of its ecosystems to an earlier time in Earth's history when multicellular life began to dominate.


title: Astrobiology

text: By understanding how extremophilic organisms can survive the Earth's extreme environments, we can also understand how microorganisms could have survived space travel and how the panspermia hypothesis could be possible.


title: Astrobiology

text: Research into the environmental limits of life and the workings of extreme ecosystems is ongoing, enabling researchers to better predict what planetary environments might be most likely to harbor life. Missions such as the "Phoenix" lander, Mars Science Laboratory, ExoMars, Mars 2020 rover to Mars, and the "Cassini" probe to Saturn's moons aim to further explore the possibilities of life on other planets in the Solar System.


title: Astrobiology

text: The two Viking landers each carried four types of biological experiments to the surface of Mars in the late 1970s. These were the only Mars landers to carry out experiments looking specifically for metabolism by current microbial life on Mars. The landers used a robotic arm to collect soil samples into sealed test containers on the craft. The two landers were identical, so the same tests were carried out at two places on Mars' surface; Viking 1 near the equator and Viking 2 further north. The result was inconclusive, and is still disputed by some scientists.


title: Astrobiology

text: Norman Horowitz was the chief of the Jet Propulsion Laboratory bioscience section for the Mariner and Viking missions from 1965 to 1976. Horowitz considered that the great versatility of the carbon atom makes it the element most likely to provide solutions, even exotic solutions, to the problems of survival of life on other planets. However, he also considered that the conditions found on Mars were incompatible with carbon based life.


title: Astrobiology

text: "Beagle 2" was an unsuccessful British Mars lander that formed part of the European Space Agency's 2003 Mars Express mission. Its primary purpose was to search for signs of life on Mars, past or present. Although it landed safely, it was unable to correctly deploy its solar panels and telecom antenna.


title: Astrobiology

text: EXPOSE is a multi-user facility mounted in 2008 outside the International Space Station dedicated to astrobiology. EXPOSE was developed by the European Space Agency (ESA) for long-term spaceflights that allow exposure of organic chemicals and biological samples to outer space in low Earth orbit.


title: Astrobiology

text: The Mars Science Laboratory (MSL) mission landed the "Curiosity" rover that is currently in operation on Mars. It was launched 26 November 2011, and landed at Gale Crater on 6 August 2012. Mission objectives are to help assess Mars' habitability and in doing so, determine whether Mars is or has ever been able to support life, collect data for a future human mission, study Martian geology, its climate, and further assess the role that water, an essential ingredient for life as we know it, played in forming minerals on Mars.


title: Astrobiology

text: The "Tanpopo" mission is an orbital astrobiology experiment investigating the potential interplanetary transfer of life, organic compounds, and possible terrestrial particles in the low Earth orbit. The purpose is to assess the panspermia hypothesis and the possibility of natural interplanetary transport of microbial life as well as prebiotic organic compounds. Early mission results show evidence that some clumps of microorganism can survive for at least one year in space. This may support the idea that clumps greater than 0.5 millimeters of microorganisms could be one way for life to spread from planet to planet.


title: Astrobiology

text: "ExoMars" is a robotic mission to Mars to search for possible biosignatures of Martian life, past or present. This astrobiological mission is currently under development by the European Space Agency (ESA) in partnership with the Russian Federal Space Agency (Roscosmos); it is planned for a 2022 launch.


title: Astrobiology

text: "Mars 2020" successfully landed its rover Perseverance in Jezero Crater on 18 February 2021. It will investigate environments on Mars relevant to astrobiology, investigate its surface geological processes and history, including the assessment of its past habitability and potential for preservation of biosignatures and biomolecules within accessible geological materials. The Science Definition Team is proposing the rover collect and package at least 31 samples of rock cores and soil for a later mission to bring back for more definitive analysis in laboratories on Earth. The rover could make measurements and technology demonstrations to help designers of a human expedition understand any hazards posed by Martian dust and demonstrate how to collect carbon dioxide (CO), which could be a resource for making molecular oxygen (O) and rocket fuel.


title: Astrobiology

text: "Europa Clipper" is a mission planned by NASA for a 2025 launch that will conduct detailed reconnaissance of Jupiter's moon Europa and will investigate whether its internal ocean could harbor conditions suitable for life. It will also aid in the selection of future landing sites.


title: Astrobiology

text: "Dragonfly" is a NASA mission scheduled to land on Titan in 2036 to assess its microbial habitability and study its prebiotic chemistry. Dragonfly is a rotorcraft lander that will perform controlled flights between multiple locations on the surface, which allows sampling of diverse regions and geological contexts.


title: Astrobiology

text: "Icebreaker Life" is a lander mission that was proposed for NASA's Discovery Program for the 2021 launch opportunity, but it was not selected for development. It would have had a stationary lander that would be a near copy of the successful 2008 "Phoenix" and it would have carried an upgraded astrobiology scientific payload, including a 1-meter-long core drill to sample ice-cemented ground in the northern plains to conduct a search for organic molecules and evidence of current or past life on Mars. One of the key goals of the "Icebreaker Life" mission is to test the hypothesis that the ice-rich ground in the polar regions has significant concentrations of organics due to protection by the ice from oxidants and radiation.


title: Astrobiology

text: "Journey to Enceladus and Titan" ("JET") is an astrobiology mission concept to assess the habitability potential of Saturn's moons Enceladus and Titan by means of an orbiter.


title: Astrobiology

text: "Enceladus Life Finder" ("ELF") is a proposed astrobiology mission concept for a space probe intended to assess the habitability of the internal aquatic ocean of Enceladus, Saturn's sixth-largest moon.


title: Astrobiology

text: "Life Investigation For Enceladus" ("LIFE") is a proposed astrobiology sample-return mission concept. The spacecraft would enter into Saturn orbit and enable multiple flybys through Enceladus' icy plumes to collect icy plume particles and volatiles and return them to Earth on a capsule. The spacecraft may sample Enceladus' plumes, the E ring of Saturn, and the upper atmosphere of Titan.


title: Astrobiology

text: "Oceanus" is an orbiter proposed in 2017 for the New Frontiers mission No. 4. It would travel to the moon of Saturn, Titan, to assess its habitability. "Oceanus" objectives are to reveal Titan's organic chemistry, geology, gravity, topography, collect 3D reconnaissance data, catalog the organics and determine where they may interact with liquid water.


title: Astrobiology

text: "Explorer of Enceladus and Titan" (ET) is an orbiter mission concept that would investigate the evolution and habitability of the Saturnian satellites Enceladus and Titan. The mission concept was proposed in 2017 by the European Space Agency.


title: Dance Dance Revolution

text: "Dance Dance Revolution" has been met with critical acclaim for its originality and stamina in the video game market, as well as popularizing the use of videogames as a medium for fitness and exercise. There have been dozens of arcade-based releases across several countries and hundreds of home video game console releases, promoting a music library of original songs produced by Konami's in-house artists and an eclectic set of licensed music from many different genres. The game is also known for its passionate fanbase, as well as its growing competitive tournament scene. The "DDR" series has also inspired similar games such as "Pump it Up" by Andamiro and "In the Groove" by Roxor Games.


title: Dance Dance Revolution

text: The core gameplay involves the player stepping their feet to correspond with the arrows that appear on the screen and the beat. During normal gameplay, arrows scroll upwards from the bottom of the screen and pass over a set of stationary arrows near the top (referred to as the "guide arrows" or "receptors", officially known as the Step Zone). When the scrolling arrows overlap the stationary ones, the player must step on the corresponding arrows on the dance platform, and the player has been given a judgment for their accuracy of every streaked note (From highest to lowest: Marvelous, Perfect, Great, Good, Almost, Miss).


title: Dance Dance Revolution

text: Additional arrow types were added in later mixes. "Freeze Arrows", introduced in "MAX", are long green arrows that must be held down until they completely travel through the Step Zone. Each of these arrows awards an "O.K.!" if successfully pressed or an "N.G." when the arrow is released too quickly. An "N.G." decreases the life bar and, starting with "X", also breaks any existing combo. "X" also introduced "Shock Arrows", walls of arrows with lightning effects that must be avoided, which will award an "O.K.!" if successfully avoided or an "N.G." if any of the dancer's panels are stepped on. An "N.G." for shock arrows has the same consequences found with freeze arrows, but hitting a shock arrow additionally hides future steps for a short period.


title: Dance Dance Revolution

text: Successfully hitting the arrows in time with the music fills the "Dance Gauge", or life bar, while failure to do so drains it. If the Dance Gauge is fully exhausted during gameplay, the player will fail the song, and the game will be over. Otherwise, the player is taken to the Results Screen, which rates the player's performance with a letter grade and a numerical score, among other statistics. The player may then be given a chance to play again, depending on the settings of the particular machine. The default limit is three songs, though operators can set the limit between one and five.


title: Dance Dance Revolution

text: Aside from play style Single, Dance Dance Revolution provides two other play styles: Versus, where two players can play Single simultaneously, and Double, where one player uses all eight panels. Before the 2013 release of "Dance Dance Revolution", some games offer additional modes, such as Course mode (players must play a set of songs back-to-back) and Battle mode (two players compete with a tug-of-war life bar by sending distracting modifiers to each other). Earlier versions also have Couple/Unison Mode, where two players must cooperate to play the song. Course Mode was reintroduced to the series starting with "A20".


title: Dance Dance Revolution

text: Depending on the edition of the game, dance steps are broken into various levels of difficulty, often by color. The difficulty is separated into two to five categories, depending on the game:


title: Dance Dance Revolution

text: The first release of "Dance Dance Revolution" established two difficulties: Basic for Single and Double modes, and Another for Single mode only. Each chart is rated with a level from 1 to 7, and every release through "3rdMix Plus" also attributed a title to each level number. The "Internet Ranking Version" added Another for Double mode, and a new higher difficulty of Maniac for Single mode only, along with several level 8 charts, titled Exorbitant. "2ndMix Club Version 2" introduced several level 9 charts, titled Catastrophic until "3rdMix Plus" and Evolutionary in "X3 vs. 2ndMix". The Maniac difficulty was renamed SSR and expanded to Double mode for new songs in "3rdMix", with the name reverting to Maniac in "3rdMix Plus". Beginning with "4thMix", all songs featured the Maniac difficulty in Single and Double mode. "4thMix Plus" introduced new Maniac charts for 16 songs, while the original Maniac charts were labelled Maniac-S and Maniac-D in this game, with only the new charts remaining in "5thMix".


title: Dance Dance Revolution

text: "DDRMAX" introduced the "Groove Radar", showing how difficult a particular sequence was in various categories, such as the maximum density of steps. This release removed the level numbers, and among the 42 songs, two ("Flash in the Night" and "Follow Me") have never received any level numbers due to being "DDRMAX" exclusives. Beginning with "DDRMAX2", level numbers were reintroduced, along with a level 10 for "MAX 300" and "MAXX Unlimited". Level 10 was titled Revolutionary in "X3 vs. 2ndMix". "DDRMAX2" also introduced the Challenge difficulty with "Kakumei" ("革命") on One More Extra Stage, and in 19 Nonstop Challenge exclusive songs. "Dance Dance Revolution Extreme" introduced the Beginner difficulty, which premiered in "Dancing Stage EuroMix", as the game's easiest difficulty. It is only available in Single mode, except in the "Dance Dance Revolution Universe" series for the Xbox 360, which offers Beginner difficulty in Single and Double modes. "Extreme" features a total of 37 songs with the Challenge difficulty.


title: Dance Dance Revolution

text: On "X", the level numbers were overhauled, now ranking songs on a scale of 1-20, the first 10 represented by yellow bars, and the second 10 represented by additional red blocks shown in place of yellow bars. All songs from previous versions were re-rated on the new scale. The same system was carried over to "X2", although the difficulty bars were removed, replaced by simple difficulty numbers with the foot mark returning as the difficulty symbol for the first time since "SuperNOVA". There is currently no song that is officially rated maximum (20); the highest rating available in 19, shared between seven songs: "POSSESSION" on Double Challenge, and "EGOISM 440", "ENDYMION", "Lachryma《Re: Queen’M》", "MAX 360", "Over The "Period", "PARANOiA Revolution", and "Valkyrie dimension" on Single Challenge and Double Challenge. However, the game still allows players to rate their custom edit data up to the maximum.


title: Dance Dance Revolution

text: The foot-rating system was completely removed for the 6th Mix, and replaced by the "Groove Radar". The Groove Radar is a graphical representation of the difficulty of a song based in five different areas: Stream, Voltage, Air, Chaos, and Freeze.


title: Dance Dance Revolution

text: Each game usually has a song that maxes out a category within the radar. If a song in a following mix or update has a higher category measurement, then the groove radar is renewed so the new song can max out that category, while all previous songs are re-rated in respect to the new radar.


title: Dance Dance Revolution

text: As of "DDR 2014", the groove radar also employs a numerical measurement in addition to a graphical representation. Before the update, the radar did not disclose the number by default, though it could be shown by holding the SELECT button while heading to the song select screen.


title: Dance Dance Revolution

text: The Groove Radar was not very popular among seasoned DDR veterans. The foot-rating system was restored to work with the Groove Radar in the North American home version of the game and the next arcade version, "MAX2", and almost all future versions (except for versions based on the North American version of "EXTREME", which only used foot ratings). All of the "MAX" songs on "MAX2" received foot-ratings, excluding songs that were removed.


title: Dance Dance Revolution

text: "SuperNOVA 2" featured special edits of songs specifically meant to max out specific categories on the radar, culminating with "DEAD END ("GROOVE RADAR" Special)", maxing out all 5 categories. While not related, "SuperNOVA 2" also featured a variation known as "My Groove Radar" as part of e-Amusement, which was also divided into five categories, though it was meant to measure the player's stats on songs rather than showing the song's difficulty.


title: Dance Dance Revolution

text: The Extra Stage, originally introduced in "1stMIX" and reintroduced in "MAX", rewards a player for clearing three songs, either with a high enough grade on the final stage or by fulfilling specific play requirements. The player receives the opportunity to play a free extra song, which often defaults to a very difficult song with forced modifiers (such as 1.5x speed and Reverse) and LIFE4 since "DDR X2", a life bar identical to the battery bar similar to Challenge mode with 1-4 lives depending on their score in the final stage in "SuperNOVA 2" and "X", or a non-regaining life bar before "SuperNOVA 2". Beginning on "SuperNOVA 2", players may be able to access the modifier menu (LIFE GAUGE is disabled) and the forced modifiers (save for battery bar or LIFE4) are no longer used. However, the Replicant-D Action event in "X2" and since "DDR 2014" did not allow players to select modifiers for its Encore Extra Stage.


title: Dance Dance Revolution

text: Before "EXTREME", the Extra Stage song was predetermined. Afterward, any song can be played for the Extra Stage, although there is still a song designated as "the" Extra Stage (usually marked with red letters on the song wheel, or contained within the EXTRA EXCLUSIVE folder. In all cases (etc. in EXTRA EXCLUSIVE songs), they must be unlocked for regular play). A player who attains a grade of "AA" (or "A" in "SuperNOVA" or 950.000 Supernova 2 points in "A") on the Extra Stage is invited to play an additional stage, "One More Extra Stage" (OMES, or Encore Extra Stage post-"SuperNOVA"), with another special song option, played in RISKY, in which any combo-breaking step or missed freeze will cause an instant failure. Since "X3 VS 2ndMIX", some Encore Extra Stage songs are marked as "ATTACK PERFECT FULL COMBO", where any judgment less than Perfect will cause the player to fail the song. Unlike Extra Stages, the song for Encore Extra Stages remains predetermined, the only exceptions were "SuperNOVA 2" and "X", which allowed players to play any song for their Encore Extra Stage. Usually, if this final boss is beaten, a special credits sequence is played.


title: Dance Dance Revolution

text: With the implementation of e-Amusement in DDR, mixes after "SuperNOVA" have contained multiple songs as extra stages, often based on specific conditions, such as playing specific difficulties or songs.


title: Dance Dance Revolution

text: From "MAX2" onward, the BPM of Extra Stage songs is displayed as a random, changing number, instead of the song's true BPM to hide it from players, also when KAKUMEI was played as an Encore Extra Stage, its Groove Radar data is hidden by continually animating through random songs' ratings. The random BPM display is replaced with the normal BPM display in the next mix, and as of "X", after the said song has been unlocked for normal play.


title: Dance Dance Revolution

text: A standard "Dance Dance Revolution" arcade machine consists of two parts, the cabinet and the dance platform. The cabinet has a wide bottom section, which houses large floor speakers and glowing neon lamps (led on X cabinets and hide lights on white cabinets). Above this sits a narrower section that contains the monitor, and on top is a lighted marquee graphic, with two small speakers and flashing lights on either side. Below the monitor are two sets of buttons (one for each player), each consisting of two triangular selection buttons (four on X and white cabinets) and a center rectangular button, used mainly to confirm a selection or start the game.


title: Dance Dance Revolution

text: The dance stage is a raised metal platform divided into two sides. Each side houses a set of four acrylic glass pads arranged and pointing in the orthogonal directions (left, up, down and right), separated by metal squares. Each pad sits atop four pressure activated switches, one at each edge of each pad, and a software-controlled cold cathode lamp illuminating the translucent pad, not available on the white cabinet. A metal safety bar in the shape of an upside-down "U" is mounted to the dance stage behind each player. Some players make use of this safety bar to help maintain proper balance, and to relieve weight from the legs so that arrows can be pressed with greater speed and accuracy.


title: Dance Dance Revolution

text: Some DDR cabinets are equipped with Sony PlayStation memory card slots, allowing the player to insert a compatible memory card before starting a game and save their high scores to the card. Additionally, the equivalent home versions of DDR allow players to create and save custom step patterns (edits) to their memory card — the player can then play those steps on the arcade machine if the same song exists on that machine. This feature is supported in 2ndMix through Extreme. On the DDR X announce, these slots are replaced by USB slots and the players required create edits from Japanese PlayStation 2's DDR X and transferred onto the DDR X arcades onwards. SuperNova series and white cabinets didn't support memory card slots. However, it introduced Konami's internet based link system "e-Amusement" to the series, which can save stats and unlocks for individual players (but cannot store edits). This functionality however, could only be used in Japan. During the North American release of Dance Dance Revolution SuperNOVA 2, an e-Amuse capable machine was made available at a Brunswick Zone Arcade in Naperville, Illinois. This machine was hosted on a different network than the Japanese version, and the only other machine on the network was located in Konami's American branch in El Segundo, California. e-Amusement functionality would later be made available in North America with the release of Dance Dance Revolution A.


title: Dance Dance Revolution

text: The Solo arcade cabinet is smaller and contains only one dance pad, modified to include six arrow panels instead of four (the additional panels are "upper-left" and "upper-right"). These pads generally don't come with a safety bar, but include the option for one to be installed at a later date. The Solo pad also lacks some of the metal plating that the standard pad has, which can make stepping difficult for players who are used to playing on standard machines. An upgrade was available for Solo machines called the "Deluxe pad", which was closer to the standard cabinet's pad. Additionally Solo machines only incorporate two sensors, located horizontally in the center of the arrow, instead of four sensors (one on each edge).


title: Dance Dance Revolution

text: On January 14, 2019, Konami revealed a new "20th Anniversary Model" cabinet redesign, featuring gold-colored plating, a larger screen, and updated dance pad LED lighting.


title: Dance Dance Revolution

text: "Dance Dance Revolution 2ndMix" was updated after its initial release with a few new songs and the ability to connect to and play alongside Konami's DJ simulator games, Beatmania IIDX. While the official name of that version of DDR when alone was "Dance Dance Revolution 2ndMix Link Version", when connected to the two Beatmania IIDX cabinets it was compatible with it was referred to by two other unique names.