The America's Cup, affectionately known as the Auld Mug, is a trophy awarded to the winner of the America's Cup match races between two sailing yachts. One yacht, known as the defender, represents the yacht club that currently holds the America's Cup and the second yacht, known as the challenger, represents the yacht club that is challenging for the cup. The timing of each match is determined by an agreement between the defender and the challenger. The America's Cup is the oldest international sporting trophy.[1][2][3] It will next be raced for in the southern summer, in the early part of 2021.[4]

The cup was originally awarded in 1851 by the Royal Yacht Squadron for a race around the Isle of Wight in the United Kingdom, which was won by the schooner America. The trophy, originally named the '£100 Cup', was renamed the America's Cup after the yacht and was donated to the New York Yacht Club (NYYC) under the terms of the Deed of Gift, which made the cup available for perpetual international competition.

Any yacht club that meets the requirements specified in the deed of gift has the right to challenge the yacht club that holds the cup. If the challenging club wins the match, it gains stewardship of the cup.

The history and prestige associated with the America's Cup attracts not only the world's top sailors and yacht designers but also the involvement of wealthy entrepreneurs and sponsors. It is a test not only of sailing skill and boat and sail design, but also of fundraising and management skills.

The trophy was held by the NYYC from 1857 (when the syndicate that won the cup donated the trophy to the club) until 1983. The NYYC successfully defended the trophy twenty-four times in a row before being defeated by the Royal Perth Yacht Club, represented by the yacht Australia II. The NYYC's reign was the longest winning streak (in terms of date) in the history of all sports.[5]

From the first defence of the cup in 1870 through the twentieth defence in 1967, there was always only one challenger. In 1970, for the first time, there were multiple challengers, so the NYYC agreed that the challengers could run a selection series with the winner becoming the official challenger and competing against the defender in the America's Cup match. Since 1983, Louis Vuitton has sponsored the Louis Vuitton Cup as a prize for the winner of the challenger selection series.

Early matches for the cup were raced between yachts 65–90 ft (20–27 m) on the waterline owned by wealthy sportsmen. This culminated with the J-Class regattas of the 1930s. After World War II and almost twenty years without a challenge, the NYYC made changes to the deed of gift to allow smaller, less expensive 12-metre class yachts to compete; this class was used from 1958 until 1987. It was replaced in 1990 by the International America’s Cup Class which was used until 2007.

After a long legal battle, the 2010 America's Cup was raced in 90 ft (27 m) waterline multihull yachts in a best of three "deed of gift" match in Valencia, Spain. The victorious Golden Gate Yacht Club then elected to race the 2013 America's Cup in AC72 foiling, wing-sail catamarans. Golden Gate Yacht Club successfully defended the cup. The 35th America's Cup match was announced to be sailed in 50 ft foiling catamarans.[6]

The history of the America's Cup has included legal battles and disputes over rule changes including most recently over the rule changes for the 2017 America's Cup.[7]

The America's Cup is currently held by the Royal New Zealand Yacht Squadron,[8] who will stage the 36th defence of the Cup in 2021.

The G20 (or Group of Twenty) is an international forum for the governments and central bank governors from 19 countries and the European Union (EU). Founded in 1999 with the aim to discuss policy pertaining to the promotion of international financial stability,[3] the G20 has expanded its agenda since 2008 and heads of government or heads of state, as well as finance ministers, foreign ministers and think tanks[4], have periodically conferred at summits ever since. It seeks to address issues that go beyond the responsibilities of any one organization.[3]

Membership of the G20 consists of 19 individual countries plus the European Union. The EU is represented by the European Commission and by the European Central Bank. Collectively, the G20 economies account for around 90%[5] of the gross world product (GWP), 80% of world trade (or, if excluding EU intra-trade, 75%), two-thirds of the world population,[2] and approximately half of the world land area.

With the G20 growing in stature[6] after its inaugural leaders' summit in 2008, its leaders announced on 25 September 2009 that the group would replace the G8 as the main economic council of wealthy nations.[7] Since its inception, the G20's membership policies have been criticized by some intellectuals,[8][9] and its summits have been a focus for major protests.[10][11]

The heads of the G20 nations held summits twice in 2009 and twice in 2010. Since the November 2011 Cannes summit, G20 summits have been held annually.[12]

The International Monetary Fund (IMF) is an international organization headquartered in Washington, D.C., consisting of 189 countries working to foster global monetary cooperation, secure financial stability, facilitate international trade, promote high employment and sustainable economic growth, and reduce poverty around the world while periodically depending on the World Bank for its resources.[1] Formed in 1944 at the Bretton Woods Conference primarily by the ideas of Harry Dexter White and John Maynard Keynes,[6] it came into formal existence in 1945 with 29 member countries and the goal of reconstructing the international payment system. It now plays a central role in the management of balance of payments difficulties and international financial crises.[7] Countries contribute funds to a pool through a quota system from which countries experiencing balance of payments problems can borrow money. As of 2016, the fund had XDR 477 billion (about US$ 667 billion).[8]

Through the fund and other activities such as the gathering of statistics and analysis, surveillance of its members' economies, and the demand for particular policies,[9] the IMF works to improve the economies of its member countries.[10] The organization's objectives stated in the Articles of Agreement are:[11] to promote international monetary co-operation, international trade, high employment, exchange-rate stability, sustainable economic growth, and making resources available to member countries in financial difficulty.[12] IMF funds come from two major sources: quotas and loans. Quotas, which are pooled funds of member nations, generate most IMF funds. The size of a member's quota depends on its economic and financial importance in the world. Nations with larger economic importance have larger quotas. The quotas are increased periodically as a means of boosting the IMF's resources in the form of special drawing rights.[13]

The current Managing Director (MD) and Chairwoman of the IMF is Bulgarian Economist Kristalina Georgieva, who has held the post since October 1, 2019.[14]

Gita Gopinath was appointed as Chief Economist of IMF from 1 October 2018. She received her PhD in economics from Princeton University. Prior to her IMF appointment she was economic adviser to the Chief Minister of Kerala, India.[15]

ITER (initially the International Thermonuclear Experimental Reactor, iter meaning "the way" or "the path" in Latin[1][2][3]) is an international nuclear fusion research and engineering megaproject aimed at replicating the fusion processes of the Sun to create energy on the Earth. Upon completion of construction of the main reactor and first plasma, planned for late 2025,[4] it will be the world's largest magnetic confinement plasma physics experiment and the largest experimental tokamak nuclear fusion reactor. It is being built next to the Cadarache facility in southern France.[5][6] ITER will be the largest of more than 100 fusion reactors built since the 1950s, with ten times the plasma volume of any other tokamak operating today.[7][8]

The long-term goal of fusion research is to generate electricity. ITER's stated purpose is scientific research, and technology demonstration of a large fusion reactor, without electricity generation.[9][7] ITERs goals are: to achieve enough fusion to produce 10 times as much thermal output power as thermal power absorbed by the plasma for short time periods; to demonstrate and test technologies that would be needed to operate a fusion power plant including cryogenics, heating, control and diagnostics systems, plus remote maintenance; to achieve and learn from a burning plasma; to test tritium breeding; and to demonstrate the safety of a fusion plant.[8][6]

ITER's thermonuclear fusion reactor will use over 300MW of electrical power to cause the plasma to absorb 50 MW of thermal power, creating 500 MW of heat from fusion for periods of 400 to 600 seconds.[10] This would mean a ten-fold gain of plasma heating power (Q), as measured by heating input to thermal output, or Q ≥ 10.[11] As of 2021, the record for energy production using nuclear fusion is held by the National Ignition Facility reactor, which achieved a Q of 0.70 in August 2021.[12] Beyond just heating the plasma, the total electricity consumed by the reactor and facilities will range from 110 MW up to 620 MW peak for 30-second periods during plasma operation.[13] As a research reactor, the heat energy generated will not be converted to electricity, but simply vented.[6][14][15]

ITER is funded and run by seven member parties: China, the European Union, India, Japan, Russia, South Korea and the United States. The United Kingdom participates through EU's Fusion for Energy (F4E), Switzerland participates through Euratom and F4E, and the project has cooperation agreements with Australia, Canada, Kazakhstan and Thailand.[16]

Construction of the ITER complex started in 2013,[17] and assembly of the tokamak began in 2020.[18] The initial budget was close to €6 billion, but the total price of construction and operations is projected to be from €18 to €22 billion;[19][20] other estimates place the total cost between $45 billion and $65 billion, though these figures are disputed by ITER.[21][22] Regardless of the final cost, ITER has already been described as the most expensive science experiment of all time,[23] the most complicated engineering project in human history,[24] and one of the most ambitious human collaborations since the development of the International Space Station (€100 billion budget) and the Large Hadron Collider (€7.5 billion budget).[25][26]

ITER's planned successor, the EUROfusion-led DEMO, is expected to be one of the first fusion reactors to produce electricity in an experimental environment.

A polar circle is a geographic term for a conditional circular line (arc) referring either to the Arctic Circle or the Antarctic Circle. These are two of the keynote circles of latitude (parallels). On Earth, the Arctic Circle is currently drifting northwards at a speed of about 14.5 m per year and is now at a mean latitude (i.e. without taking into account the astronomical nutation) of 66°33′48.9″ N; the Antarctic Circle is currently drifting southwards at a speed of about 14.5 m per year and is now at a mean latitude (i.e. without taking into account the astronomical nutation) of 66°33′48.9″ S.[1] Polar circles are often equated with polar regions of Earth. Due to their inherent climate environment, the bulk of the Arctic Circle, much of which is sea, is sparsely settled whereas this applies to all of Antarctica which is mainly land and sheltered ice shelves.

If Earth had no atmosphere then both polar circles (arcs) would see a day a year when the center of the sun is continuously above the horizon and at a day a year when it is always below the horizon – a polar day and a polar night as is the case for longer, within the circles. Up to and including the associated poles (North and South), known geographically as the frigid zones such duration extends up to half of the year, namely, close to the poles. Instead, atmospheric refraction and the Sun's light reaching the planet as an extended object rather than a point source means that just within each circle the Earth's surface does not experience any proper polar night, 24 hours where the sun does not rise. By these same two factors, just outward of each circle still experiences a polar day (a day in which the sun does not fully set).

The latitude of the polar circles is + or −90 degrees (which refers to the North and South Pole, respectively) minus the axial tilt (that is, of the Earth's axis of daily rotation relative to the ecliptic, the plane of the Earth's orbit). This predominant, average tilt of the Earth varies slightly, a phenomenon described as nutation. Therefore, the latitudes noted above are calculated by averaging values of tilt observed over many years. The axial tilt also exhibits long-term variations as described in the reference article (a difference of 1 second of arc (″) in the tilt is equivalent to change of about 31 metres north or south in the positions of the polar circles on the Earth's surface).