naked eye observation is available for only a small part of the stars that fill the universe.However, they are sufficient to assess all the grandeur of the cosmos.In the list of the most prominent stars on the twelfth place is Altair - the star, often occupy the minds of astronomers.
Location
simply find the light, not only because of its brightness.Located star Altair in the constellation of the Eagle, is an impressive part of the sky, and generally well marked.Name shone clearly indicates its origin.It is formed from the "Al-Nasr al-Tair," which in Arabic means "the flying eagle".
ideal time to observe the celestial figure - from June to August.Eagle belongs to the equatorial constellations, and therefore more visible in the central and southern regions of our country, while in the northern regions is available for study.This heavenly figure lies to the south-west of the Swan.Explore Eagle easily by three stars that make an almost perfect straight line.It is Altair, and Tarazed Alshain.Also, astronomers combined their asterism in the balance beam.
hero legend
Altair - a star, not a single member of the asterism.The most famous combination of light with his participation is the Summer Triangle."Companion" Altair in it - it Vega (Lyra) and Deneb (Cygnus constellation).All the bright components of asterism, well marked.Since ancient times, they were participants in a variety of legends.In one of them appears Altair shepherd who once a year, on the night of Ivan Kupala, meets his beloved Vega, a weaver.
Options
easy to guess that the heavenly picture of the Eagle is the brightest star - Altair (alpha constellation).It is the light of the spectral class is not far ahead of the Sun in size.Weight Altair 1.7 times more than its argument, about the same proportion are the diameters of the two celestial bodies.Brightness Alpha Eagle - largely the result of its relative proximity to the Earth.Altair is separated from the Sun by about 16.8 light-years.In addition, Alpha Eagle brighter than our star.The luminosity of Altair is nine times greater than the sun.
Quick
Altair - a star known not only because of its brightness and visibility.It is characterized by a very rapid rotation around its axis.One revolution of the star performs over a period of 6 to 10 hours (in different sources of information is somewhat different).To appreciate this speed can be, if we remember that the sun is required for this is much more time - 25 days.
This speed has its consequences.Altair - a star-shaped ellipse.Rapid rotation led to squeezed light near the poles.As a result, the diameter of the star at the equator is 22% more than the polar.Initially, flattened shape Altair was discovered in the course of theoretical calculations, but in 2007, scientists have proof of loyalty to these constructions.
Difficulties
Experts of the Center of Astronomy of the University of Georgia's high-resolution, led by John Monnier selected Altair as an object for study.It was supposed to make a snapshot of the surface of the sun.The formed image would be first to demonstrate so close to a star outside the solar system.However, for such luminaries sized photos Altair, located at the same distance, you need a telescope with a mirror of three hundred meters in diameter.For the current level of technology such equipment - in the future.
obvious problem has not stopped scientists.To work it was used four telescopes, arranged in a circle with a diameter of 250 m. The light caught them, gathered in the device, known as "Michigan Infrared unifier".The result was obtained by precision-light image.The results of the study
star Altair, whose photo was made with a resolution of less than one millisecond corner, appeared such a theory predicts - flattened near the poles.However, most scientists are not interested in it.The pictures showed different parts of the surface brightness of stars.It was seen some spots, dark and light.In addition, the observed differences in the brightness of the star's photosphere latitude.
observed features Altair have not yet received an explanation.The adopted concept of a uniformly rotating stars, they do not fit.The findings need to be further detailed study with the help of new equipment and special technologies.Methods of optical interferometry can be used to study the surface and other nearby stars.
star Altair in astrology related including with the ability to predictions penchant thoughts ahead of the era.Perhaps it is no coincidence that shone encourages scientists to improve their equipment.Failure to receive new knowledge about Altair old research methods, some inexplicable phenomena in the framework of the traditional theories - all this stimulates the movement of scientific thought and technology available to progress.Still Alpha Eagle, as well as all the constellation of interest to amateur astronomers.Close enough to the location and brightness, combined with insufficient knowledge - that's the reason for such close attention to the Altair.Probably in the near future, scientists will delight us with new discoveries related to this star.
