Yerevan vs Vega

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Yerevan (UK: YERR-ə-VAN, US: -⁠VAHN; Armenian: Երևան [jɛɾɛˈvɑn] (listen), sometimes spelled Erevan) is the capital and largest city of Armenia and one of the world's oldest continuously inhabited cities. Situated along the Hrazdan River, Yerevan is the administrative, cultural, and industrial center of the country. It has been the capital since 1918, the fourteenth in the history of Armenia and the seventh located in or around the Ararat plain. The city also serves as the seat of the Araratian Pontifical Diocese; the largest diocese of the Armenian Apostolic Church and one of the oldest dioceses in the world.The history of Yerevan dates back to the 8th century BC, with the founding of the fortress of Erebuni in 782 BC by King Argishti I at the western extreme of the Ararat plain. Erebuni was "designed as a great administrative and religious centre, a fully royal capital." By the late ancient Armenian Kingdom, new capital cities were established and Yerevan declined in importance. Under Iranian and Russian rule, it was the center of the Erivan Khanate from 1736 to 1828 and the Erivan Governorate from 1850 to 1917, respectively. After World War I, Yerevan became the capital of the First Republic of Armenia as thousands of survivors of the Armenian Genocide in the Ottoman Empire arrived in the area. The city expanded rapidly during the 20th century as Armenia became part of the Soviet Union. In a few decades, Yerevan was transformed from a provincial town within the Russian Empire to Armenia's principal cultural, artistic, and industrial center, as well as becoming the seat of national government.

With the growth of the Armenian economy, Yerevan has undergone major transformation. Much construction has been done throughout the city since the early 2000s, and retail outlets such as restaurants, shops, and street cafés, which were rare during Soviet times, have multiplied. As of 2011, the population of Yerevan was 1,060,138, just over 35% of the Republic of Armenia's total population. According to the official estimate of 2016, the current population of the city is 1,073,700. Yerevan was named the 2012 World Book Capital by UNESCO. Yerevan is an associate member of Eurocities.Of the notable landmarks of Yerevan, Erebuni Fortress is considered to be the birthplace of the city, the Katoghike Tsiranavor church is the oldest surviving church of Yerevan and Saint Gregory Cathedral is the largest Armenian cathedral in the world, Tsitsernakaberd is the official memorial to the victims of the Armenian Genocide, and several opera houses, theatres, museums, libraries, and other cultural institutions. Yerevan Opera Theatre is the main spectacle hall of the Armenian capital, the National Gallery of Armenia is the largest art museum in Armenia and shares a building with the History Museum of Armenia, and the Matenadaran repository contains one of the largest depositories of ancient books and manuscripts in the world.

Source: Wikipedia

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Vega is the brightest star in the northern constellation of Lyra. It has the Bayer designation α Lyrae, which is Latinised to Alpha Lyrae and abbreviated Alpha Lyr or α Lyr. This star is relatively close at only 25 light-years from the Sun, and, together with Arcturus and Sirius, one of the most luminous stars in the Sun's neighborhood. It is the fifth-brightest star in the night sky, and the second-brightest star in the northern celestial hemisphere, after Arcturus. Vega has been extensively studied by astronomers, leading it to be termed "arguably the next most important star in the sky after the Sun". Vega was the northern pole star around 12,000 BC and will be so again around the year 13,727, when its declination will be +86° 14′. Vega was the first star other than the Sun to be photographed and the first to have its spectrum recorded. It was one of the first stars whose distance was estimated through parallax measurements. Vega has functioned as the baseline for calibrating the photometric brightness scale and was one of the stars used to define the zero point for the UBV photometric system.

Vega is only about a tenth of the age of the Sun, but since it is 2.1 times as massive, its expected lifetime is also one tenth of that of the Sun; both stars are at present approaching the midpoint of their life expectancies. Vega has an unusually low abundance of the elements with a higher atomic number than that of helium. Vega is also a variable star that varies slightly in brightness. It is rotating rapidly with a velocity of 236 km/s at the equator. This causes the equator to bulge outward due to centrifugal effects, and, as a result, there is a variation of temperature across the star's photosphere that reaches a maximum at the poles. From Earth, Vega is observed from the direction of one of these poles.Based on an observed excess emission of infrared radiation, Vega appears to have a circumstellar disk of dust. This dust is likely to be the result of collisions between objects in an orbiting debris disk, which is analogous to the Kuiper belt in the Solar System. Stars that display an infrared excess due to dust emission are termed Vega-like stars.

Source: Wikipedia