Sun vs Stralsund

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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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Stralsund (German pronunciation: [ˈʃtʁaːlzʊnt]), Swedish: Strålsund) is a Hanseatic city in the Pomeranian part of Mecklenburg-Vorpommern, Germany. It is located at the southern coast of the Strelasund, a sound of the Baltic Sea separating the island of Rügen from the mainland.The Strelasund Crossing with its two bridges and several ferry services connects Stralsund with Rügen. The Western Pomeranian city has been the capital of the Vorpommern-Rügen district since the 2011 district reforms. It is the fourth-largest city of Mecklenburg-Vorpommern and, together with Greifswald, Stralsund forms an Oberzentrum, one of four high-level urban centers of the region.

Stralsund was granted city rights in 1234 and was one of the most prospering members of the medieval Hanseatic League. In 1628, during the Thirty Years' War, the city came under Swedish rule and remained so until the upheavals of the Napoleonic Wars. From 1815 to 1945, Stralsund was part of Prussia. Since 2002, Stralsund's old town with its rich heritage is honored as a UNESCO World Heritage, along with Wismar in Mecklenburg. The main industries of Stralsund are shipyards, fishing, mechanical engineering, and, to an increasing degree, tourism, life sciences, services and high tech industries, especially information technology and biotechnology.

Source: Wikipedia