Sun vs Gifu

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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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Gifu (岐阜市, Gifu-shi) is a city located in the south-central portion of Gifu Prefecture, Japan, and serves as the prefectural capital. The city has played an important role in Japan's history because of its location in the middle of the country. During the Sengoku period, various warlords, including Oda Nobunaga, used the area as a base in an attempt to unify and control Japan. Gifu continued to flourish even after Japan's unification as both an important shukuba along the Edo period Nakasendō and, later, as one of Japan's fashion centers. It has been designated a core city by the national government. Located on the alluvial plain of the Nagara River, Gifu has taken advantage of the surrounding natural resources to create both traditional industries (including Mino washi and agriculture) and tourism opportunities such as cormorant fishing. Mount Kinka, one of the city's major symbols, is home to a nationally designated forest and Gifu Castle, a replica of Nobunaga's former castle.

Gifu also hosts many festivals and events throughout the year. Two major rail lines connect Gifu to Japan's national and international transportation infrastructure. JR Central's Tōkaidō Main Line runs through the city, connecting it with Nagoya, one of Japan's largest cities, and the surrounding area. The city has a direct train route to Chubu Centrair International Airport and facilities capable of hosting international events. Gifu has active relationships with six sister cities. As of 1 June 2019, the city has an estimated population of 401,534 in 178,246 households, and a population density of about 1,972 inhabitants per square kilometre (5,110/sq mi). The total area of the city was 203.60 square kilometers (78.61 sq mi).

Source: Wikipedia