Sun vs Lyon

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The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (864,000 miles), or 109 times that of Earth, and its mass is about 330,000 times that of Earth. It accounts for 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, including oxygen, carbon, neon, and iron.The Sun is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). 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 gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.

In its core the Sun currently fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second as a result. 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 to the point at which the Sun is no longer in hydrostatic equilibrium, its core will undergo a marked increase in density and temperature while its outer layers expand, eventually transforming the Sun into a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury and Venus, and render Earth uninhabitable – but not for about five billion years. After this, it will shed its outer layers and become a dense type of cooling star known as a white dwarf, and no longer produce energy by fusion, but still glow and give off heat from its previous fusion. The enormous effect of the Sun on Earth has been recognized since prehistoric times. The Sun has been regarded by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of solar calendars, one of which is the predominant calendar in use today.

Source: Wikipedia

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Lyon or Lyons (UK: , US: , French: [ljɔ̃] (listen); Francoprovençal: Liyon, pronounced [ʎjɔ̃]; Italian: Lione, pronounced [liˈone]) is the third-largest city and second-largest urban area of France. It is located at the confluence of the rivers Rhône and Saône, about 470 km (292 mi) south-east of Paris, 320 km (199 mi) north of Marseille and 56 km (35 mi) northeast of Saint-Étienne. Inhabitants of the city are called Lyonnais. The city of Lyon proper had a population of 516,092 in 2017 within its small municipal territory of 48 km2 (19 sq mi), but together with its suburbs and exurbs the Lyon metropolitan area had a population of 2,323,221 that same year, the second-most populated in France. The city of Lyon and 58 suburban municipalities have formed since 2015 the Metropolis of Lyon, a directly elected metropolitan authority now in charge of most urban issues, with a population of 1,385,927 in 2017.Lyon is the capital of the region of Auvergne-Rhône-Alpes as well as the seat of the Rhône departmental council (whose jurisdiction, however, no longer extends over the Metropolis of Lyon since 2015). Former capital of the Gauls at the time of the Roman Empire, Lyon is the seat of an archbishopric whose holder bears the title of Primate of the Gauls.

Lyon became a major economic hub during the Renaissance. The city is recognized for its cuisine and gastronomy, and historical and architectural landmarks; as such, the districts of Old Lyon, the Fourvière hill, the Presqu'île and the slopes of the Croix-Rousse are inscribed on the UNESCO world heritage list. Lyon was historically an important area for the production and weaving of silk. Lyon played a significant role in the history of cinema: it is where Auguste and Louis Lumière invented the cinematograph. It is also known for its light festival, the Fête des Lumières, which begins every 8 December and lasts for four days, earning Lyon the title of Capital of Lights. Economically, Lyon is a major centre for banking, as well as for the chemical, pharmaceutical, and biotech industries. The city contains a significant software industry with a particular focus on video games, and in recent years has fostered a growing local start-up sector. Lyon hosts the international headquarters of Interpol, the International Agency for Research on Cancer and Euronews. According to the Globalization and World Rankings Research Institute, Lyon is considered a Beta city, as of 2018. It ranked second in France and 40th globally in Mercer's 2019 liveability rankings.

Source: Wikipedia