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3,200 | On 31 December 2021, the ground team extended the two telescoping "mid booms" from the left and right sides of the observatory. The left side deployed in 3 hours and 19 minutes; the right side took 3 hours and 42 minutes. Commands to separate and tension the membranes followed between 3 and 4 January and were successfu... | https://en.wikipedia.org/wiki?curid=434221 |
3,201 | The last step of structural deployment was to unfold the wings of the primary mirror. Each panel consists of three primary mirror segments and had to be folded to allow the space telescope to be installed in the fairing of the Ariane rocket for the launch of the telescope. On 7 January 2022, NASA deployed and locked in... | https://en.wikipedia.org/wiki?curid=434221 |
3,202 | On 24 January 2022, at 2:00p.m. EST, nearly a month after launch, a third and final course correction took place, inserting JWST into its planned halo orbit around the Sun–Earth L point. | https://en.wikipedia.org/wiki?curid=434221 |
3,203 | The MIRI instrument has four observing modes—imaging, low-resolution spectroscopy, medium-resolution spectroscopy and coronagraphic imaging. “ On Aug. 24, a mechanism that supports medium-resolution spectroscopy (MRS), exhibited what appears to be increased friction during setup for a science observation. This mechanis... | https://en.wikipedia.org/wiki?curid=434221 |
3,204 | On 12 January 2022, while still in transit, mirror alignment began. The primary mirror segments and secondary mirror were moved away from their protective launch positions. This took about 10 days, because the 132 actuator motors are designed to fine-tune the mirror positions at microscopic accuracy (10 nanometer incre... | https://en.wikipedia.org/wiki?curid=434221 |
3,205 | Mirror alignment requires each of the 18 mirror segments, and the secondary mirror, to be positioned to within 50 nanometers. NASA compares the required accuracy by analogy: "If the Webb primary mirror were the size of the United States, each [mirror] segment would be the size of Texas, and the team would need to line ... | https://en.wikipedia.org/wiki?curid=434221 |
3,206 | Mirror alignment was a complex operation split into seven phases, that had been repeatedly rehearsed using a 1:6 scale model of the telescope. Once the mirrors reached , NIRCam targeted the 6th magnitude star HD 84406 in Ursa Major. To do this, NIRCam took 1560 images of the sky and used these wide-ranging images to de... | https://en.wikipedia.org/wiki?curid=434221 |
3,207 | With the mirrors now positioned for almost correct images, they had to be fine tuned to their operational accuracy of 50 nanometers, less than one wavelength of the light that will be detected. A technique called "dispersed fringe sensing" was used to compare images from 20 pairings of mirrors, allowing most of the err... | https://en.wikipedia.org/wiki?curid=434221 |
3,208 | In preparation for alignment, NASA announced at 19:28 UTC on 3 February 2022, that NIRCam had detected the telescope's first photons (although not yet complete images). On 11 February 2022, NASA announced the telescope had almost completed phase 1 of alignment, with every segment of its primary mirror having located an... | https://en.wikipedia.org/wiki?curid=434221 |
3,209 | JWST observing time is allocated through a General Observers (GO) program, a Guaranteed Time Observations (GTO) program, and a Director's Discretionary Early Release Science (DD-ERS) program. The GTO program provides guaranteed observing time for scientists who developed hardware and software components for the observa... | https://en.wikipedia.org/wiki?curid=434221 |
3,210 | In November 2017, the Space Telescope Science Institute announced the selection of 13 Director's Discretionary Early Release Science (DD-ERS) programs, chosen through a competitive proposal process. The observations for these programs were to be obtained during the first five months of JWST science operations after the... | https://en.wikipedia.org/wiki?curid=434221 |
3,211 | For GO Cycle 1 there were 6,000 hours of observation time available to allocate, and 1,173 proposals were submitted requesting a total of 24,500 hours of observation time. Selection of Cycle 1 GO programs was announced on 30 March 2021, with 266 programs approved. These include 13 large programs and treasury programs p... | https://en.wikipedia.org/wiki?curid=434221 |
3,212 | The first full-color images and spectroscopic data were released on 12 July 2022, which also marked the official beginning of Webb's general science operations; President Joe Biden revealed the first image, "Webb's First Deep Field", on 11 July 2022. NASA announced the list of observations targeted for release: | https://en.wikipedia.org/wiki?curid=434221 |
3,213 | On 14 July 2022, NASA presented images of Jupiter and related areas captured, for the first time, and including infrared views, by the James Webb Space Telescope. | https://en.wikipedia.org/wiki?curid=434221 |
3,214 | In a preprint released around the same time, NASA, ESA and CSA scientists stated that "almost across the board, the science performance of JWST is better than expected". The document described a series of observations during the commissioning, when the instruments captured spectra of transiting exoplanets with a precis... | https://en.wikipedia.org/wiki?curid=434221 |
3,215 | Within two weeks of the first Webb images, several preprint papers described a wide range of early galaxies believed to date from 235 million years (z=16.7) to 280 million years after the Big Bang, far earlier than previously known. The results await peer review. On 17 August 2022, NASA released a large mosaic image of... | https://en.wikipedia.org/wiki?curid=434221 |
3,216 | On 24 August 2022, astronomers published the first detailed scientific result for the telescope on the detection of carbon dioxide in the atmosphere of the gas giant exoplanet WASP-39b from transmission spectroscopy observations obtained with JWST as part of the Early Release Science program (ERS). It was the first con... | https://en.wikipedia.org/wiki?curid=434221 |
3,217 | The 2021 FIA Formula One World Championship was a motor racing championship for Formula One cars which was the 72nd running of the Formula One World Championship. It is recognised by the Fédération Internationale de l'Automobile (FIA), the governing body of international motorsport, as the highest class of competition ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,218 | At season's end in Abu Dhabi, Max Verstappen of Red Bull Racing-Honda won the Drivers' Championship for the first time in his career. Verstappen became the first ever driver from the Netherlands, the first Honda-powered driver since Ayrton Senna in 1991, the first Red Bull driver since Sebastian Vettel in 2013 and the ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,219 | Honda became the second engine supplier in the turbo-hybrid era to power a championship winning car, after Mercedes. Four-time defending and seven-time champion Lewis Hamilton of Mercedes finished runner up. Mercedes retained the Constructors' Championship for the eighth consecutive season. | https://en.wikipedia.org/wiki?curid=57373873 |
3,220 | The season ended with a controversial finish, with the two title rivals for the drivers' crown entering the last race of the season with equal points. Verstappen sealed the title after winning the season-ending Abu Dhabi Grand Prix after a last-lap restart pass on Hamilton following a contentious conclusion of a safety... | https://en.wikipedia.org/wiki?curid=57373873 |
3,221 | This was the first season since 2008 where the champion driver was not from the team that took the constructors' title. The season was also the final season in the sport for 2007 World Champion Kimi Räikkönen. | https://en.wikipedia.org/wiki?curid=57373873 |
3,222 | The following constructors and drivers were under contract to compete in the 2021 World Championship. All teams competed with tyres supplied by Pirelli. Each team was required to enter at least two drivers, one for each of the two mandatory cars. | https://en.wikipedia.org/wiki?curid=57373873 |
3,223 | Across the season, five drivers drove as a test or third driver in free practice sessions. Callum Ilott and Robert Kubica drove for Alfa Romeo Racing at two and three Grands Prix respectively, while Roy Nissany and Jack Aitken drove for Williams at three Grands Prix and at the Abu Dhabi Grand Prix, respectively. Zhou G... | https://en.wikipedia.org/wiki?curid=57373873 |
3,224 | McLaren announced that they would change from using Renault power units to ones built by Mercedes, resuming the McLaren-Mercedes partnership that ran between and . Racing Point became known as Aston Martin. The name change was brought about by the team's part owner Lawrence Stroll investing in the Aston Martin marque. ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,225 | Four-time World Drivers' Champion Sebastian Vettel left Ferrari at the end of the Championship after racing with the team for six seasons. Vettel's seat was taken by Carlos Sainz Jr., who had left McLaren. Daniel Ricciardo moved from Renault to McLaren, where he replaced Sainz. Ricciardo was replaced by double World Ch... | https://en.wikipedia.org/wiki?curid=57373873 |
3,226 | Vettel moved to Aston Martin, where he replaced Sergio Pérez. Pérez, who had previously signed a contract to drive for Aston Martin's predecessor, Racing Point, until 2022, moved to Red Bull Racing where he replaced Alexander Albon, who was Red Bull Racing's reserve and test driver for the 2021 season. Pérez became the... | https://en.wikipedia.org/wiki?curid=57373873 |
3,227 | Romain Grosjean and Kevin Magnussen, who had raced for Haas since and respectively, left the team at the end of 2020. 2020 Formula 2 Champion Mick Schumacher, the son of seven-time World Champion Michael Schumacher, took one of the seats at the team while the other was filled by Nikita Mazepin, who finished fifth in th... | https://en.wikipedia.org/wiki?curid=57373873 |
3,228 | Yuki Tsunoda, who finished third in 2020 Formula 2 Championship, graduated to Formula One with Scuderia AlphaTauri, replacing Daniil Kvyat, who moved to Alpine as their reserve driver. Tsunoda became the first Japanese Formula One driver since Kamui Kobayashi in . | https://en.wikipedia.org/wiki?curid=57373873 |
3,229 | During the Dutch Grand Prix weekend, Kimi Räikkönen tested positive for coronavirus. He was replaced at Alfa Romeo Racing by reserve driver Robert Kubica, who last raced at the 2019 Abu Dhabi Grand Prix, driving for Williams. Räikkönen was also replaced by Kubica at the subsequent Italian Grand Prix. | https://en.wikipedia.org/wiki?curid=57373873 |
3,230 | The 2021 calendar consisted of twenty-two events, which were subject to the permissive COVID-19 regulations set by local governments and the Formula One Group. | https://en.wikipedia.org/wiki?curid=57373873 |
3,231 | Liberty Media, the sport's commercial rights holders, announced that there would be scope for the 2021 calendar to expand beyond the planned twenty-two races of the 2020 calendar. The sporting regulations were amended to allow for a maximum of twenty-five Grands Prix per year. | https://en.wikipedia.org/wiki?curid=57373873 |
3,232 | Further changes to the calendar are planned following the disruption to the 2020 championship brought about by the COVID-19 pandemic: | https://en.wikipedia.org/wiki?curid=57373873 |
3,233 | Liberty Media was also reported to have come to an agreement in principle with race organisers to host a second race in the United States. Plans to hold the race at a circuit in Miami Gardens were unveiled. A second proposal to move the former Brazilian Grand Prix from São Paulo to a new circuit in Rio de Janeiro was a... | https://en.wikipedia.org/wiki?curid=57373873 |
3,234 | The original calendar that was approved by the FIA World Motor Sport Council included the Chinese Grand Prix, which was due to take place on 11 April. However, the event was postponed and later cancelled, due to travel restrictions. The at the Autodromo Enzo e Dino Ferrari in Imola, which was originally intended to be ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,235 | On 28 April 2021, the Canadian Grand Prix was cancelled for a second consecutive year and was replaced by the Turkish Grand Prix, originally intended to make a one-off return in 2020. On 14 May 2021, the Turkish Grand Prix was postponed due to the British government imposing a ten-day hotel quarantine on travellers fro... | https://en.wikipedia.org/wiki?curid=57373873 |
3,236 | On 18 August 2021, the Japanese Grand Prix was cancelled for a second consecutive year. The race calendar was revised again on 28 August 2021, consisting of twenty-two Grands Prix, with the Turkish, Mexico City and São Paulo Grands Prix moved a week later, the round in which the cancelled Australian Grand Prix was due ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,237 | The 2021 championship was originally due to introduce significant changes to the regulations, including the sport's governance, car designs and the sporting rules but these were delayed in March 2020 in response to the disruption caused by the COVID-19 pandemic. These rule changes were instead introduced in . | https://en.wikipedia.org/wiki?curid=57373873 |
3,238 | The championship introduced a budget cap, with teams limited to spending a maximum of $145 million per year. Teams were required to use more commercially available materials and to submit their annual expenditure. Some teams argued to further reduce the budget cap to $100 million, citing concerns that the long-term fin... | https://en.wikipedia.org/wiki?curid=57373873 |
3,239 | The value of the budget cap was set for twenty-one races; each additional race increased the budget cap by $1 million, and vice versa: each race removed from the scheduled twenty-one race calendar deducted the budget cap by $1 million. However, the budget cap did not include marketing budget, drivers' salaries, and the... | https://en.wikipedia.org/wiki?curid=57373873 |
3,240 | Teams were limited in what components could be modified for the 2021 season, with this requirement introduced to ease financial pressures on teams brought about by the COVID-19 pandemic. The teams were allowed to apply for special dispensation to make changes, most notably in the case of McLaren, who were given permiss... | https://en.wikipedia.org/wiki?curid=57373873 |
3,241 | Some aerodynamic rule changes were enacted by the FIA. The floor of the cars were 'clipped' in order to reduce downforce for 2021. In 2020, the floor was permitted to run in a straight line from an area adjacent to the cockpit back to a point ahead of the rear tyre. However, from 2021 that point ahead of the tyre was m... | https://en.wikipedia.org/wiki?curid=57373873 |
3,242 | The "dual-axis steering" (DAS) system developed by Mercedes in 2020 was banned, starting from 2021. The DAS system allowed the driver to adjust the toe of the front wheels to optimise mechanical grip by pulling or pushing on the steering wheel. The FIA introduced newly revised wing load tests mid-season at the French G... | https://en.wikipedia.org/wiki?curid=57373873 |
3,243 | From the Belgian Grand Prix onwards a new technical directive was enforced surrounding pit stop equipment after concerns teams were flouting the article 12.8.4 of Formula One technical regulations that state that pit equipment may only be filled with compressed air or nitrogen and that sensors on this equipment must 'a... | https://en.wikipedia.org/wiki?curid=57373873 |
3,244 | It was originally proposed that teams would be required to allow a driver who had competed in fewer than two to replace one of their race drivers in a Friday practice session over the course of the season. Whilst these rules were intended to give a chance to more non-Formula One drivers to test a Formula One car, the w... | https://en.wikipedia.org/wiki?curid=57373873 |
3,245 | Following the Mercedes tyre error during the 2020 Sakhir Grand Prix, where George Russell was given front tyres allocated to Valtteri Bottas during a pit stop, the FIA had adjusted the rules on tyre usage; drivers using mixed compound sets or using sets allocated to another driver on their cars were permitted to comple... | https://en.wikipedia.org/wiki?curid=57373873 |
3,246 | For the 2021 season, the schedule of a race weekend was revised. Under the pre-existing regulations, a race weekend spanned four days, with the Thursday before the race being reserved for media and promotional events and scrutineering; however, under the new regulations all of Thursday's events were moved to the Friday... | https://en.wikipedia.org/wiki?curid=57373873 |
3,247 | There were a trial of sprint qualifying at the British, Italian, and São Paulo Grands Prix. Qualifying for these sprints took place on Friday afternoon in place of the normal second practice session and the sprints ran over the least number of laps to exceed , approximately one third of a normal race distance. The resu... | https://en.wikipedia.org/wiki?curid=57373873 |
3,248 | Winter testing switched from the Circuit de Barcelona-Catalunya in Montmeló to the Bahrain International Circuit in Sakhir, with three days of running beginning on 12 March. Formula One declined an offer from Bahrain to provide COVID-19 vaccines for all personnel attending pre-season testing and the season's opening Gr... | https://en.wikipedia.org/wiki?curid=57373873 |
3,249 | Max Verstappen took pole position on the opening round in Bahrain. On the formation lap, Sergio Pérez stalled at the last turn and was relegated to start in the pit lane, leaving his 11th place spot vacant. On the first lap, Nikita Mazepin spun at turn 3, crashing into the barrier and calling out the safety car. AlphaT... | https://en.wikipedia.org/wiki?curid=57373873 |
3,250 | At the Emilia Romagna Grand Prix, Hamilton took pole from Pérez and Verstappen. Verstappen went into the lead at turn 1 on lap 1, after it started raining on race day. Mazepin and Nicholas Latifi crashed at the exit of turn 13, bringing out the safety car. Under the safety car, Schumacher lost control of his car and sp... | https://en.wikipedia.org/wiki?curid=57373873 |
3,251 | Bottas took pole at the . He kept his lead from Hamilton and Verstappen. On lap 2, Kimi Räikkönen made contact with his teammate, Antonio Giovinazzi, and was forced into retirement, while Giovinazzi could continue. Hamilton eventually overtook Bottas and won with Verstappen in second and Bottas in third. Pérez and Norr... | https://en.wikipedia.org/wiki?curid=57373873 |
3,252 | Hamilton took his 100th pole position in Spain. On lap 1, Verstappen overtook him at the first turn. Five laps later, Yuki Tsunoda pulled over at the reprofiled turn 10, marking his first Formula One retirement. Hamilton took the lead after Verstappen pitted on lap 23, but Verstappen took it back on lap 28. However, a ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,253 | Leclerc took pole at the Monaco Grand Prix despite crashing in the final minutes. The crash caused a driveshaft failure, meaning he was unable to start the race. Verstappen started at the front and led from Bottas and Carlos Sainz Jr. On lap 30, Bottas was forced into retirement after his front-right tyre would not com... | https://en.wikipedia.org/wiki?curid=57373873 |
3,254 | Leclerc took pole again in Azerbaijan, this time he was able to start the race. He led for one lap before Hamilton got past on lap 2 at turn 1. Hamilton was held up in his pitstop to allow Gasly to pass him in the pitlane, handing Verstappen the net race lead. On lap 30, Lance Stroll crashed out due to a tyre failure a... | https://en.wikipedia.org/wiki?curid=57373873 |
3,255 | In France, Verstappen got his second pole of the season, only to go wide at the first turn and lose the lead to Hamilton in the first lap. After regaining first with an undercut in his first pit stop, Verstappen found himself under heavy pressure from both Mercedes drivers. Verstappen relinquished his lead to pit a sec... | https://en.wikipedia.org/wiki?curid=57373873 |
3,256 | Max Verstappen took his third season pole at the Styrian Grand Prix, the first of two back-to-back races at the Red Bull Ring. On the first lap, three cars collided at the third turn, forcing Pierre Gasly out of the race. Verstappen won from Lewis Hamilton, meaning Verstappen extended his title lead to 18 points. Valtt... | https://en.wikipedia.org/wiki?curid=57373873 |
3,257 | Hamilton was fastest in qualifying to start in first place for the first ever sprint in the British Grand Prix. In the sprint, Verstappen made a better start than Hamilton and overtook him before the first corner, leading every lap and winning the sprint with Hamilton second and Bottas third, thus Verstappen started on... | https://en.wikipedia.org/wiki?curid=57373873 |
3,258 | Hamilton was again fastest in qualifying to take pole in the Hungarian Grand Prix. Rainy conditions at the start of the race led to Bottas misjudging his braking and sliding into the back of Norris; this escalated into multiple collisions which eventually eliminated five drivers: Bottas, Norris (who only retired on lap... | https://en.wikipedia.org/wiki?curid=57373873 |
3,259 | Verstappen took pole from Russell and Hamilton in the Belgian Grand Prix in a wet qualifying session. The race was heavily affected by rain, which initially saw the start delayed by 25 minutes. After two formation laps behind the safety car, the race start was suspended and red-flagged due to poor conditions and lack o... | https://en.wikipedia.org/wiki?curid=57373873 |
3,260 | Verstappen would again take pole at the first Dutch Grand Prix to take place since 1985 at Zandvoort. He held his lead from Hamilton to take the win at his home race, taking over the lead of the championship by three points. Bottas came third, overtaking Norris, who finished tenth, in the standings for third place. Bot... | https://en.wikipedia.org/wiki?curid=57373873 |
3,261 | Verstappen was required to start from the back at the Russian Grand Prix for exceeding his quota of a number of his power unit components. Norris took his first career pole position, from Sainz (his best qualifying result), and Russell. The running order changed substantially as heavy rain began to fall in the closing ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,262 | Lewis Hamilton was the fastest in qualifying in Turkey, but was dropped down the grid because of a penalty due to a power unit component change. Valtteri Bottas was promoted to pole position and won the race, his first of 2021. He was followed by Max Verstappen, who re-took the championship lead, and Sergio Pérez, who ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,263 | Hamilton was fastest in qualifying in Brazil, but was disqualified the following day for a technical infringement. Bottas won the qualifying sprint, giving him pole position for the Grand Prix. By finishing second in the sprint, Verstappen increased his championship lead over Hamilton by two points, and Carlos Sainz Jr... | https://en.wikipedia.org/wiki?curid=57373873 |
3,264 | Hamilton took pole position in Qatar, while a penalty for failing to respect double waived yellow flags during qualifying forced Verstappen to start from seventh. Hamilton took the win, leading every lap of the race. Verstappen quickly recovered to second place but was unable to threaten Hamilton's race lead despite se... | https://en.wikipedia.org/wiki?curid=57373873 |
3,265 | Hamilton took pole position again in the inaugural Saudi Arabian Grand Prix ahead of Bottas and Verstappen, who crashed at the last corner of his final qualifying lap. The race played host to several incidents which saw the retirements of Schumacher, Pérez, George Russell, Nikita Mazepin, and Sebastian Vettel, with Ham... | https://en.wikipedia.org/wiki?curid=57373873 |
3,266 | Verstappen took the pole position in Abu Dhabi ahead of Hamilton and Norris. During the race, Hamilton had a better start and took the lead into the first turn. At turn six Verstappen attempted to pass, forcing Hamilton to evade by going off the track. Emerging from the corner still in the lead, Hamilton was instructed... | https://en.wikipedia.org/wiki?curid=57373873 |
3,267 | Mercedes lodged two separate protests against the race's result. Both protests were dismissed, and Mercedes announced their intention to appeal the dismissal of the protest regarding the handling of the restart following the safety car period. | https://en.wikipedia.org/wiki?curid=57373873 |
3,268 | A statement from the FIA acknowledged the controversy, and that it was "tarnishing the image of the championship and the due celebration". The statement was made after a meeting of the FIA World Motor Sport Council, which was scheduled for 15 December 2021, and was described as "extending an olive branch to Mercedes". ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,269 | Following an FIA investigation and inquiry, Masi was removed from his role as race director, being replaced by Niels Wittich and Eduardo Freitas, with Herbie Blash appointed as a permanent senior advisor alongside Wittich and Freitas. | https://en.wikipedia.org/wiki?curid=57373873 |
3,270 | On 10 March 2022 the FIA World Motor Sport Council report on the events of the final race of the season was announced, and that the "Race Director called the safety car back into the pit lane without it having completed an additional lap as required by the Formula 1 Sporting Regulations", however also noted that the "r... | https://en.wikipedia.org/wiki?curid=57373873 |
3,271 | In October 2022, the FIA published their review of the teams' budgets for 2021. Red Bull Racing had committed a minor financial breach (defined as less than 5% over budget) of , which would be when adjusted for tax. Additionally, both Aston Martin and Red Bull were found to have made procedural breaches. Red Bull were ... | https://en.wikipedia.org/wiki?curid=57373873 |
3,272 | Points are awarded to the top ten classified drivers, the driver who set the fastest lap during the Grand Prix, but only if one of the top ten, and the top three of the sprint qualifying. In the case of a tie on points a countback system is used where the driver with the most first places is ranked higher. If the numbe... | https://en.wikipedia.org/wiki?curid=57373873 |
3,273 | The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radiation, and is the most important source of energy for life on Earth. | https://en.wikipedia.org/wiki?curid=26751 |
3,274 | The Sun's radius is about , or 109 times that of Earth. Its mass is about 330,000 times that of Earth, comprising about 99.86% of the total mass of the Solar System. Roughly three-quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, ... | https://en.wikipedia.org/wiki?curid=26751 |
3,275 | The Sun is a G-type main-sequence star (G2V). As such, it is informally, and not completely accurately, referred to as a yellow dwarf (its light is actually white). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gat... | https://en.wikipedia.org/wiki?curid=26751 |
3,276 | Every second, the Sun's core fuses about 600 million tons of hydrogen into helium, and in the process converts 4 million tons of matter into energy. This energy, which can take between 10,000 and 170,000 years to escape the core, is the source of the Sun's light and heat. When hydrogen fusion in its core has diminished... | https://en.wikipedia.org/wiki?curid=26751 |
3,277 | The enormous effect of the Sun on Earth has been recognized since prehistoric times. The Sun was thought of by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of some solar calendars. The predominant calendar in use today is the Gregorian calendar which is based upon t... | https://en.wikipedia.org/wiki?curid=26751 |
3,278 | The English word "sun" developed from Old English . Cognates appear in other Germanic languages, including West Frisian , Dutch , Low German , Standard German , Bavarian , Old Norse , and Gothic . All these words stem from Proto-Germanic . This is ultimately related to the word for "sun" in other branches of the Indo-E... | https://en.wikipedia.org/wiki?curid=26751 |
3,279 | The principal adjectives for the Sun in English are "sunny" for sunlight and, in technical contexts, "solar" (), from Latin – the latter found in terms such as "solar day", "solar eclipse" and "Solar System" (occasionally "Sol system"). From the Greek comes the rare adjective "heliac" (). In English, the Greek and Lati... | https://en.wikipedia.org/wiki?curid=26751 |
3,280 | The English weekday name "Sunday" stems from Old English "sun's day", a Germanic interpretation of the Latin phrase , itself a translation of the ancient Greek () 'day of the sun'. The astronomical symbol for the Sun is a circle with a center dot, . It is used for such units as "M" (Solar mass), "R" (Solar radius) and ... | https://en.wikipedia.org/wiki?curid=26751 |
3,281 | The Sun is a G-type main-sequence star that constitutes about 99.86% of the mass of the Solar System. The Sun has an absolute magnitude of +4.83, estimated to be brighter than about 85% of the stars in the Milky Way, most of which are red dwarfs. The Sun is a Population I, or heavy-element-rich, star. The formation of ... | https://en.wikipedia.org/wiki?curid=26751 |
3,282 | The Sun is by far the brightest object in the Earth's sky, with an apparent magnitude of −26.74. This is about 13 billion times brighter than the next brightest star, Sirius, which has an apparent magnitude of −1.46. | https://en.wikipedia.org/wiki?curid=26751 |
3,283 | The Sun does not have a definite boundary, but its density decreases exponentially with increasing height above the photosphere. For the purpose of measurement, the Sun's radius is considered to be the distance from its center to the edge of the photosphere, the apparent visible surface of the Sun. By this measure, the... | https://en.wikipedia.org/wiki?curid=26751 |
3,284 | The Sun is composed primarily of the chemical elements hydrogen and helium. At this time in the Sun's life, they account for 74.9% and 23.8%, respectively, of the mass of the Sun in the photosphere. All heavier elements, called "metals" in astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the ... | https://en.wikipedia.org/wiki?curid=26751 |
3,285 | The Sun's original chemical composition was inherited from the interstellar medium out of which it formed. Originally it would have contained about 71.1% hydrogen, 27.4% helium, and 1.5% heavier elements. The hydrogen and most of the helium in the Sun would have been produced by Big Bang nucleosynthesis in the first 20... | https://en.wikipedia.org/wiki?curid=26751 |
3,286 | Since the Sun formed, the main fusion process has involved fusing hydrogen into helium. Over the past 4.6 billion years, the amount of helium and its location within the Sun has gradually changed. Within the core, the proportion of helium has increased from about 24% to about 60% due to fusion, and some of the helium a... | https://en.wikipedia.org/wiki?curid=26751 |
3,287 | The chemical composition of the photosphere is normally considered representative of the composition of the primordial Solar System. The solar heavy-element abundances described above are typically measured both using spectroscopy of the Sun's photosphere and by measuring abundances in meteorites that have never been h... | https://en.wikipedia.org/wiki?curid=26751 |
3,288 | The core of the Sun extends from the center to about 20–25% of the solar radius. It has a density of up to (about 150 times the density of water) and a temperature of close to 15.7 million Kelvin (K). By contrast, the Sun's surface temperature is approximately . Recent analysis of SOHO mission data favors a faster rota... | https://en.wikipedia.org/wiki?curid=26751 |
3,289 | The core is the only region in the Sun that produces an appreciable amount of thermal energy through fusion; 99% of the power is generated within 24% of the Sun's radius, and by 30% of the radius, fusion has stopped nearly entirely. The remainder of the Sun is heated by this energy as it is transferred outwards through... | https://en.wikipedia.org/wiki?curid=26751 |
3,290 | The proton–proton chain occurs around times each second in the core, converting about 3.7 protons into alpha particles (helium nuclei) every second (out of a total of ~8.9 free protons in the Sun), or about . However, each proton (on average) takes around 9 billion years to fuse with one another using the PP chain. Fus... | https://en.wikipedia.org/wiki?curid=26751 |
3,291 | The fusion rate in the core is in a self-correcting equilibrium: a slightly higher rate of fusion would cause the core to heat up more and expand slightly against the weight of the outer layers, reducing the density and hence the fusion rate and correcting the perturbation; and a slightly lower rate would cause the cor... | https://en.wikipedia.org/wiki?curid=26751 |
3,292 | The radiative zone is the thickest layer of the sun, at 0.45 solar radii. From the core out to about 0.7 solar radii, thermal radiation is the primary means of energy transfer. The temperature drops from approximately 7 million to 2 million Kelvin with increasing distance from the core. This temperature gradient is les... | https://en.wikipedia.org/wiki?curid=26751 |
3,293 | The radiative zone and the convective zone are separated by a transition layer, the tachocline. This is a region where the sharp regime change between the uniform rotation of the radiative zone and the differential rotation of the convection zone results in a large shear between the two—a condition where successive hor... | https://en.wikipedia.org/wiki?curid=26751 |
3,294 | The Sun's convection zone extends from 0.7 solar radii (500,000 km) to near the surface. In this layer, the solar plasma is not dense enough or hot enough to transfer the heat energy of the interior outward via radiation. Instead, the density of the plasma is low enough to allow convective currents to develop and move ... | https://en.wikipedia.org/wiki?curid=26751 |
3,295 | The thermal columns of the convection zone form an imprint on the surface of the Sun giving it a granular appearance called the solar granulation at the smallest scale and supergranulation at larger scales. Turbulent convection in this outer part of the solar interior sustains "small-scale" dynamo action over the near-... | https://en.wikipedia.org/wiki?curid=26751 |
3,296 | The visible surface of the Sun, the photosphere, is the layer below which the Sun becomes opaque to visible light. Photons produced in this layer escape the Sun through the transparent solar atmosphere above it and become solar radiation, sunlight. The change in opacity is due to the decreasing amount of H ions, which ... | https://en.wikipedia.org/wiki?curid=26751 |
3,297 | The photosphere is tens to hundreds of kilometers thick, and is slightly less opaque than air on Earth. Because the upper part of the photosphere is cooler than the lower part, an image of the Sun appears brighter in the center than on the edge or "limb" of the solar disk, in a phenomenon known as limb darkening. The s... | https://en.wikipedia.org/wiki?curid=26751 |
3,298 | During early studies of the optical spectrum of the photosphere, some absorption lines were found that did not correspond to any chemical elements then known on Earth. In 1868, Norman Lockyer hypothesized that these absorption lines were caused by a new element that he dubbed "helium", after the Greek Sun god Helios. T... | https://en.wikipedia.org/wiki?curid=26751 |
3,299 | The coolest layer of the Sun is a temperature minimum region extending to about above the photosphere, and has a temperature of about . This part of the Sun is cool enough to allow the existence of simple molecules such as carbon monoxide and water, which can be detected via their absorption spectra. | https://en.wikipedia.org/wiki?curid=26751 |
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