Elk vs Vega

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The elk (Cervus canadensis) or wapiti is one of the largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in North America and Northeast Asia. This animal should not be confused with the still larger moose (Alces alces) of North America, alternatively known as "elk" in British English and related names in other European languages (German Elch, Swedish älg, French élan), in reference to populations in Eurasia. Elk range in forest and forest-edge habitat, feeding on grasses, plants, leaves, and bark. Male elk have large antlers which are shed each year. Males also engage in ritualized mating behaviors during the rut, including posturing, antler wrestling (sparring), and bugling, a loud series of vocalizations that establishes dominance over other males and attracts females. Although it is currently native to North America and eastern Asia, it had a much wider distribution in the past. Populations were present across Eurasia into Western Europe during the Late Pleistocene, and survived into the early Holocene in southern Sweden and the Alps.

The elk has adapted well in countries where it has been introduced, including Argentina and New Zealand. Its adaptability may in fact threaten endemic species and the ecosystems into which it has been introduced. Elk are susceptible to a number of infectious diseases, some of which can be transmitted to livestock. Efforts to eliminate infectious diseases from elk populations, largely by vaccination, have had mixed success. Some cultures revere the elk as having spiritual significance. In parts of Asia, antlers and their velvet are used in traditional medicines. Elk are hunted as a game species. Their meat is leaner and higher in protein than beef or chicken. Elk were long believed to belong to a subspecies of the European red deer (Cervus elaphus), but evidence from many mitochondrial DNA genetic studies beginning in 1998 shows that the two are distinct species. Key morphological differences that distinguish C. canadensis from C. elaphus are the former's wider rump patch and paler-hued antlers.

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