Qom vs Vega

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Qom (Persian: قم‎ [ɢom] (listen)) is the seventh largest metropolis and also the seventh largest city in Iran. Qom is the capital of Qom Province. It is located 140 km (87 mi) to the south of Tehran. At the 2016 census, its population was 1,201,158. It is situated on the banks of the Qom River. Qom is considered holy in Shi'a Islam, as it is the site of the shrine of Fatimah bint Musa, sister of Imam Ali ibn Musa Rida (Persian: Imam Reza; 789–816). The city is the largest center for Shi'a scholarship in the world, and is a significant destination of pilgrimage, with around twenty million pilgrims visiting the city every year, the majority being Iranians but also other Shi'a Muslims from all around the world.

Qom is also famous for a Persian brittle toffee known as sohan (Persian: سوهان), considered a souvenir of the city and sold by 2,000 to 2,500 "sohan" shops. Qom has developed into a lively industrial centre owing in part to its proximity to Tehran. It is a regional centre for the distribution of petroleum and petroleum products, and a natural gas pipeline from Bandar Anzali and Tehran and a crude oil pipeline from Tehran run through Qom to the Abadan refinery on the Persian Gulf. Qom gained additional prosperity when oil was discovered at Sarajeh near the city in 1956 and a large refinery was built between Qom and Tehran.

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