Bologna vs Vega

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Bologna (, UK also , Italian: [boˈloɲɲa] (listen); Bolognese: Bulåggna [buˈlʌɲːa]; Latin: Bonōnia) is the capital and largest city of the Emilia-Romagna region in Northern Italy. It is the seventh most populous city in Italy with about 390,000 inhabitants and 150 different nationalities. Its metropolitan area is home to more than 1,000,000 people.Originally Etruscan, the city has been one of the most important urban centres for centuries, first under the Etruscans (who called it Felsina), then under the Celts as Bona, later under the Romans (Bonōnia), then again in the Middle Ages, as a free municipality and signoria, when it was among the largest European cities by population. Famous for its towers, churches and lengthy porticoes, Bologna has a well-preserved historical centre, thanks to a careful restoration and conservation policy which began at the end of the 1970s. Home to the oldest university in the Western world, the University of Bologna, established in AD 1088, the city has a large student population that gives it a cosmopolitan character.

In 2000 it was declared European capital of culture and in 2006, a UNESCO "City of Music" and became part of the Creative Cities Network.Bologna is an important agricultural, industrial, financial and transport hub, where many large mechanical, electronic and food companies have their headquarters as well as one of the largest permanent trade fairs in Europe. According to the most recent data gathered by the European Regional Economic Growth Index (E-REGI) of 2009, Bologna is the first Italian city and the 47th European city in terms of its economic growth rate. As a consequence, Bologna is also one of the wealthiest cities in Italy, often ranking as one of the top cities in terms of quality of life in the country: in 2020 it ranked 1st out of 107 Italian provinces.

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