25 Facts About Vega


Vega is the brightest star in the northern constellation of Lyra.

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Vega has been extensively studied by astronomers, leading it to be termed "arguably the next most important star in the sky after the Sun".

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Vega was the first star other than the Sun to have its image and spectrum photographed.

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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.

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Vega is only about a tenth of the age of the Sun, but since it is 2.

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Vega is a variable star that varies slightly in brightness.

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From Earth, Vega is observed from the direction of one of these poles.

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At latitudes to the north of 51° N, Vega remains continuously above the horizon as a circumpolar star.

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Vega is the brightest of the successive northern pole stars.

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On 17 July 1850, Vega became the first star to be photographed, when it was imaged by William Bond and John Adams Whipple at the Harvard College Observatory, with a daguerreotype.

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Distance to Vega can be determined by measuring its parallax shift against the background stars as the Earth orbits the Sun.

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Vega is one of six A0V stars that were used to set the initial mean values for this photometric system when it was introduced in the 1950s.

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The magnitude of Vega was measured again in 1981 at the David Dunlap Observatory and showed some slight variability.

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Vega became the first solitary main-sequence star beyond the Sun known to be an X-ray emitter when in 1979 it was observed from an imaging X-ray telescope launched on an Aerobee 350 from the White Sands Missile Range.

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In 1983, Vega became the first star found to have a disk of dust.

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At present, Vega has more than twice the mass of the Sun and its bolometric luminosity is about 40 times the Sun's.

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Energy flux from Vega has been precisely measured against standard light sources.

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The visual spectrum of Vega is dominated by absorption lines of hydrogen; specifically by the hydrogen Balmer series with the electron at the n=2 principal quantum number.

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The X-ray emission from Vega is very low, demonstrating that the corona for this star must be very weak or non-existent.

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However, this discrepancy can be explained if Vega is a rapidly rotating star that is being viewed from the direction of its pole of rotation.

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Radial velocity of Vega is the component of this star's motion along the line-of-sight to the Earth.

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Models fitted to the dust distribution around Vega indicate that it is a 120-astronomical-unit-radius circular disk viewed from nearly pole-on.

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The disk of dust is produced as radiation pressure from Vega pushes debris from collisions of larger objects outward.

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The inclination of planetary orbits around Vega is likely to be closely aligned to the equatorial plane of this star.

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In Zoroastrianism, Vega was sometimes associated with Vanant, a minor divinity whose name means "conqueror".

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