Vega - Visibility

Visibility

Vega can often be seen near the zenith in the mid-northern latitudes during the evening in the Northern Hemisphere summer. From mid-southern latitudes, it can be seen low above the northern horizon during the Southern Hemisphere winter. With a declination of +38.78°, Vega can only be viewed at latitudes north of 51° S. Therefore, it does not rise at all anywhere in Antarctica or in the southernmost part of South America, including Punta Arenas, Chile (53° S). At latitudes to the north of +51° N, Vega remains continually above the horizon as a circumpolar star. Around July 1, Vega reaches midnight culmination when it crosses the meridian at that time.

This star lies at a vertex of a widely spaced asterism called the Summer Triangle, which consists of the zero-magnitude stars Vega in the constellation Lyra and Altair in Aquila, plus the first magnitude star Deneb in Cygnus. This formation is the approximate shape of a right triangle, with Vega located at its right angle. The Summer Triangle is recognizable in the northern skies for there are few other bright stars in its vicinity. Vega can be identified easily because Altair and its two neighbouring stars form a line which points at Vega.

The Lyrids is a strong meteor shower that peaks each year during April 21–22. When a small meteor enters the Earth's atmosphere at a high velocity, it produces a streak of light as the object is vaporized. During a shower, a multitude of meteors arrive from the same direction, and, from the perspective of an observer, their glowing trails appear to radiate from a single point in space. In the case of the Lyrids, the meteor trails radiate from the direction of Lyra, and hence are sometimes called the Alpha Lyrids. However, they actually originated from debris emitted by the comet C/1861 G1 Thatcher and have nothing to do with the star.

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