Vega is a bright star just 25 light-years from Earth, visible in the summer sky of the Northern Hemisphere. The star is part of the constellation Lyra and forms an asterism with the stars Deneb and Altair that is known as the Summer Triangle.
Because the Earth's axis wobbles, north gradually shifts to different stars over a 26,000-year cycle. Vega was the North Star several thousand years ago, and will become the North Star again in about 12,000 years.
Vega is almost directly overhead in mid-northern latitudes on mid-summer nights. Also, from mid-northern latitudes such as New York or Madrid, Vega goes below the horizon for only seven hours a day and can be seen on any night of the year.
Farther south, Vega is below the horizon for a longer interval of time, but in Alaska, northern Canada and much of Europe, Vega never sets. Vega's location is:
- Right Ascension: 18h 36m 56.3s
- Declination: 38 degrees 47 minutes 01 second
Because Vega's blue-white light is so bright — it has an apparent magnitude of 0.03 — it features prominently in ancient cultures ranging from the Chinese to the Polynesians to the Hindu. Its name comes from the Arabic word waqi, which means "falling" or "swooping."
"This is a reference to the time when people regarded the constellation Lyra as a swooping vulture rather than a lyre," wrote Michael Anissimov on the website wiseGEEK.
The name of Vega and other astronomical targets symbolize the traditional importance of astronomy in Islam, noted one researcher, because following the stars allowed believers to mark the times of prayer and festivals, as well as to find the holy city of Mecca.
"Thus hundreds of stars and constellations have Arabic names, such as Altair, Deneb, Vega and Rigel," wrote Nidhal Guessoum, a professor of physics and astronomy at the American University of Sharjah in the United Arab Emirates in a 2013 Nature article.
In more modern times, Vega was the first star to be photographed, other than the sun. Astronomers captured the image through the daguerreotype process at Harvard Observatory, using a 15-inch refractor, on July 16-17, 1850.
The star also was chosen for the first spectrographic image; in 1872, Henry Draper was the first to break down Vega's light to show the various elements that make up the star.
Vega in recent years
Vega rose to prominence in popular culture in the late 1990s after Carl Sagan's book Contact was adapted into a Hollywood movie. Starring Jodie Foster, the story followed an astronomer working for the Search for Extraterrestrial Intelligence (SETI) who discovers a signal appearing to emanate from Vega.
Telescopic observations in 2006 revealed Vega is whipping around so quickly that its poles are several thousand degrees warmer than the equator. The star, which rotates every 12.5 hours, is at 90 percent of its critical rotation speed, or the velocity at which it would tear itself apart.
In early 2013, astronomers announced they had discovered an asteroid belt surrounding Vega – possibly pointing to planets within the rocks' midst. The layout (which was similar to findings near the star Fomalhaut) suggests there are two areas: icy asteroids in the outer area, and warmer space rocks closer to the star.
"Overall, the large gap between the warm and the cold belts is a signpost that points to multiple planets likely orbiting around Vega and Fomalhaut," said Kate Su, an astronomer at the Steward Observatory at the University of Arizona, at the American Astronomical Society 2013 annual meeting.
— Elizabeth Howell, SPACE.com Contributor