Toulon vs Vega

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Toulon (UK: , US: , French: [tulɔ̃]; Provençal: Tolon (classical norm), Touloun (Mistralian norm), pronounced [tuˈlun]) is a city on the French Riviera and a large port on the Mediterranean coast, with a major naval base. Located in the Provence-Alpes-Côte d'Azur region, Toulon is the capital of the Var department. The Commune of Toulon has a population of 171,953 people (2017), making it France's 14th-largest city. It is the centre of an urban unit with 575,347 inhabitants (2017), the ninth largest in France.

Toulon is the third-largest French city on the Mediterranean coast after Marseille and Nice. Toulon is an important centre for naval construction, fishing, wine making, and the manufacture of aeronautical equipment, armaments, maps, paper, tobacco, printing, shoes, and electronic equipment. The military port of Toulon is the major naval centre on France's Mediterranean coast, home of the French aircraft carrier Charles de Gaulle and her battle group. The French Mediterranean Fleet is based in Toulon.

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