SEPTEMBER 12Standing almost directly overhead as darkness falls on mid-September evenings is the brilliant bluish-white star, Vega, in the constellation of Lyra, the Harp. Its the fifth brightest star in the entire sky; third brightest visible from mid-northern latitudes, behind Sirius and Arcturus.
Also, as seen from mid-northern latitudes such as New York or Madrid, Vega goes below the horizon for only about seven hours a day, meaning that you can see it on any night of the year. Farther south, Vega is below the horizon for an even longer stretch of time. Conversely, for Alaska, central and northern Canada, as well as central and northern Europe, Vega never sets and is readily visible on any night of the year.
Vega is the brightest of the three stars forming the large "Summer Triangle" consisting of Vega, Altair and Deneb. It is located 25 light years away, has a diameter approximately three times that of our Sun and is 58 times more luminous.
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| NightSky Friday | |
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 | SKY MAP: The Summer Triangle as it looks at about 9 p.m. from mid-northern latitudes on Sept. 12. For orientation, Vega is almost directly overhead at this time. On subsequent nights, the stars are in almost the same positions at this time.
| | * Graphic made with Starry Night Software | | | |
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| A closer look at Lyra and the objects of interest within, also for 9 p.m. local time.
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| Lyra as the ancients saw it.
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Observations of Vega in 1983 with the Infrared Astronomy Satellite provided the first evidence for large dust particles around another star, probably debris related to the formation of planets. This discovery likely inspired Carl Sagan to place a planet orbiting Vega in his novel "Contact."
In January 2002, astronomers at the Harvard-Smithsonian Center for Astrophysics announced that features observed in a cloud of dust swirling around Vega may be the signatures of an unseen planet in an eccentric orbit around the star.
Vega also holds a rather unique place in the annals of astronomy as being the first star ever to be photographed. The historic photograph was made using the daguerreotype process at Harvard Observatory on the night of July 16-17, 1850. A 15-inch refractor was used, but nonetheless it still took an exposure of 100-seconds for Vegas image to register.
Lyra was supposed to represent Apollos harp.
Officially, Lyra is a lyre a stringed instrument of the harp family used to accompany a singer or reader of poetry, especially in ancient Greece. Six stars form a combined geometric pattern of a parallelogram and an equal-sided triangle attached at its northern corner. Vega gleams at the western point of the triangle.
But there are other interesting sights to explore here.
Epsilon Lyrae, at the northern point of the little triangle where Vega is located, is known as the "double-double" star. Good eyesight reveals Epsilon is really a close pair of stars. Binoculars readily separate the two, while a moderately large telescope shows each one divided again into two stars.
The star Sheliak is one of the two that forms the southern side of the parallelogram and appears to diminish by half of its normal brightness about every 13 days when its eclipsed by a darker companion star.
Between this winking star and its neighbor, Sulafat is the famous Ring Nebula, faintly glowing like a ghostly doughnut or a cosmic smoke ring. Visible only in large telescopes, it appears as an oval ring around a star. Millions of years ago, this star exploded, hurling out great masses of gas. We see the star now through the thin part of this gaseous envelope.
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Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for The New York Times and other publications, and he is also an on-camera meteorologist for News 12 Westchester, New York.
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