Sun vs Riga

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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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Riga (; Latvian: Rīga [ˈriːɡa] (listen), Livonian: Rīgõ) is the capital of Latvia and is home to 627,487 inhabitants (2020), which is a third of Latvia's population. Being significantly larger than other cities of Latvia, Riga is the country's primate city. It is also the largest city in the three Baltic states and is home to one tenth of the three Baltic states' combined population. The city lies on the Gulf of Riga at the mouth of the Daugava river where it meets the Baltic Sea. Riga's territory covers 307.17 km2 (118.60 sq mi) and lies 1–10 m (3 ft 3 in–32 ft 10 in) above sea level, on a flat and sandy plain.Riga was founded in 1201 and is a former Hanseatic League member. Riga's historical centre is a UNESCO World Heritage Site, noted for its Art Nouveau/Jugendstil architecture and 19th century wooden architecture.

Riga was the European Capital of Culture in 2014, along with Umeå in Sweden. Riga hosted the 2006 NATO Summit, the Eurovision Song Contest 2003, the 2006 IIHF Men's World Ice Hockey Championships and the 2013 World Women's Curling Championship. It is home to the European Union's office of European Regulators for Electronic Communications (BEREC). In 2017, it was named the European Region of Gastronomy. In 2016, Riga received over 1.4 million visitors. The city is served by Riga International Airport, the largest and busiest airport in the Baltic states. Riga is a member of Eurocities, the Union of the Baltic Cities (UBC) and Union of Capitals of the European Union (UCEU).

Source: Wikipedia