Tallinn vs Aurora

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Tallinn (; Estonian: [ˈtɑlʲˑinˑ]; names in other languages) is the capital, primate and the most populous city of Estonia. Located in the northern part of the country, on the shore of the Gulf of Finland of the Baltic Sea, it has a population of 437,619 in 2020. Administratively a part of Harju County, Tallinn is the main financial, industrial and cultural centre of Estonia; the second largest city, Tartu, is located in the southern part of Estonia, 187.2 kilometres (116.3 mi) southeast of Tallinn. Tallinn is located 80.32 kilometres (49.91 mi) south of Helsinki, Finland, 320.56 kilometres (199.19 mi) west of Saint Petersburg, Russia, 300.84 kilometres (186.93 mi) north of Riga, Latvia, and 380 kilometres (240 mi) east of Stockholm, Sweden. It has close historical ties with these four cities. From the 13th century until the first half of the 20th century Tallinn was known in most of the world by its historical German name Reval. Tallinn, first mentioned in 1219, received city rights in 1248, but the earliest human settlements date back 5,000 years.

The first recorded claim over the land was laid by Denmark in 1219, after a successful raid of Lyndanisse led by King Valdemar II, followed by a period of alternating Scandinavian and Teutonic rulers. Due to its strategic location, the city became a major trade hub, especially from the 14th to the 16th century, when it grew in importance as part of the Hanseatic League. Tallinn's Old Town in Kesklinn is one of the best preserved medieval cities in Europe and is listed as a UNESCO World Heritage Site.Tallinn has the highest number of start-ups per person among European countries and is a birthplace of many international high technology companies, including Skype and Transferwise. The city is to house the headquarters of the European Union's IT agency. Providing to the global cybersecurity it is the home to the NATO Cyber Defence Centre of Excellence. Tallinn is ranked as a global city and has been listed among the top ten digital cities in the world. The city was a European Capital of Culture for 2011, along with Turku in Finland.

Source: Wikipedia

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An aurora (plural: auroras or aurorae), sometimes referred to as polar lights (aurora polaris), northern lights (aurora borealis), or southern lights (aurora australis), is a natural light display in the Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras are the result of disturbances in the magnetosphere caused by solar wind. These disturbances are sometimes strong enough to alter the trajectories of charged particles in both solar wind and magnetospheric plasma. These particles, mainly electrons and protons, precipitate into the upper atmosphere (thermosphere/exosphere).

The resulting ionization and excitation of atmospheric constituents emit light of varying color and complexity. The form of the aurora, occurring within bands around both polar regions, is also dependent on the amount of acceleration imparted to the precipitating particles. Precipitating protons generally produce optical emissions as incident hydrogen atoms after gaining electrons from the atmosphere. Proton auroras are usually observed at lower latitudes.

Source: Wikipedia