Vega vs Louisville

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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

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Louisville ( (listen), US: (listen) LOO-ə-vəl , locally (listen)) is the largest city in the Commonwealth of Kentucky and the 29th most-populous city in the United States. It is one of two cities in Kentucky designated as first-class, the other being Lexington, the state's second-largest city. Louisville is the historical seat and, since 2003, the nominal seat of Jefferson County, on the Indiana border. Named after King Louis XVI of France, Louisville was founded in 1778 by George Rogers Clark, making it one of the oldest cities west of the Appalachians. With nearby Falls of the Ohio as the only major obstruction to river traffic between the upper Ohio River and the Gulf of Mexico, the settlement first grew as a portage site. It was the founding city of the Louisville and Nashville Railroad, which grew into a 6,000-mile (9,700 km) system across 13 states. Today, the city is known as the home of legendary boxer Muhammad Ali, the Kentucky Derby, Kentucky Fried Chicken (KFC), the University of Louisville and its Cardinals, Louisville Slugger baseball bats, and three of Kentucky's six Fortune 500 companies: Humana, Kindred Healthcare, and Yum! Brands.

Muhammad Ali International Airport, Louisville's main commercial airport, hosts UPS's worldwide hub. Since 2003, Louisville's borders have been the same as those of Jefferson County, after a city-county merger. The official name of this consolidated city-county government is the Louisville/Jefferson County Metro Government, abbreviated to Louisville Metro. Despite the merger and renaming, the term "Jefferson County" continues to be used in some contexts in reference to Louisville Metro, particularly including the incorporated cities outside the "balance" which make up Louisville proper. The city's total consolidated population as of the 2019 census estimate was 766,757. However, the balance total of 617,638 excludes other incorporated places and semiautonomous towns within the county and is the population listed in most sources and national rankings. The Louisville-Jefferson County, KY-IN Metropolitan Statistical Area (MSA) includes Louisville-Jefferson County and 12 surrounding counties, seven in Kentucky and five in Southern Indiana. As of 2019, the MSA had a population of 1,265,108, ranking 46th nationally.

Source: Wikipedia