Viseu vs Vega

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Viseu (Portuguese pronunciation: [viˈzew] (listen)) is a city and municipality in the Centro Region of Portugal and the capital of the district of the same name, with a population of 100,000 inhabitants, and center of the Viseu Dão Lafões intermunipical community, with 267,633 inhabitants. Settled during the period of the early Iberian Castro culture, the territory of Viseu was populated by a series of cultures including the Romans, Suebs, Visigoths and Moors. During the Roman occupation of Iberia, Viriathus, rebel leader of the Lusitanians, is assumed to have lived for a time in the vicinity.

During the Middle Ages, the city often served as seat for Visigothic nobles (such as King Roderic), and is considered one of the probable birthplaces of Afonso Henriques, first King of Portugal.Viseu is a regional economic hub with a strong wine industry and is the seat of international conglomerate Visabeira. The city is also a cultural center, home to the nationally acclaimed Grão Vasco Museum, seat of the Roman Catholic Diocese of Viseu, and pole of national universities, including the Catholic University of Portugal.

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