Vega vs Irbid

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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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Irbid (Arabic: إرْبِد‎), known in ancient times as Arabella or Arbela (Άρβηλα in Ancient Greek), is the capital and largest city of the Irbid Governorate. It also has the second largest metropolitan population in Jordan after Amman, with a population of around 1,911,600. Irbid is located about 70 kilometres (43 mi) north of Amman on the northern ridge of the Gilead, equidistant from Pella, Beit Ras (Capitolias), and Um Qais, and approximately 20 kilometres (12 mi) south of the Syrian border. Irbid was built on successive Early Bronze Age settlements and was possibly the biblical Beth Arbel and the Arbila of the Decapolis, a Hellenistic league of the 1st century BCE through the 2nd century CE.

The population of Irbid swelled in the late 19th century, and prior to 1948 it served as a significant centre of transit trade.Irbid is the second largest metropolitan in Jordan by population after Amman. But as a city Irbid is the third largest one after Amman and Az Zarqa. The province of Irbid Governorate has the second largest population, and the highest population density in the kingdom. The city is a major ground transportation hub between Amman, Syria to the north, and Mafraq to the east. The Irbid region is also home to several colleges and universities. The two most prominent universities are Jordan University of Science and Technology and Yarmouk University.

Source: Wikipedia