Ekşi Duyuru

In Japanese mythology, Alcor is known as the lifespan star or "jumyouboshi" as it was believed that one who could not see this star would pass away by year's end. Of incidental note, the popular Japanese manga, Fist of the North Star, used this legend as a model for its death omen star, in which it was said that people who saw the star would die later in the year.
"The Arabs in the desert regarded it as a test of penetrating vision; and they were accustomed to oppose "Suhel" to "Suha" (Canopus to Alcor) as occupying respectively the highest and lowest posts in the celestial hierarchy. So that Vidit Alcor, at non lunam plenam, (Latin for "he saw Alcor, but not the full moon") came to be a proverbial description of one keenly alive to trifles, but dull of apprehension for broad facts."
Al Sahja was the rhythmical form of the usual Suha; and it appears as Al "Khawwar," the Faint One, in an interesting list of Arabic star-names, published in Popular Astronomy for January, 1895, by Professor Robert H. West, of the Syrian Protestant College at Beirut.
The 14th century Arabian lexicographer Al Firuzabadi called it Our Riddle, and Al Sadak, the Test,—correctly Saidak, True; while the 13th century Persian astronomical writer Al Kazwini said that "people tested their eyesight by this star." Humboldt wrote of it as being seen with difficulty, and Arago similarly alluded to it; but some now consider it brighter than formerly {p.446} and no longer the difficult object that it was, even in the clear sky of the Desert; or as having increased in angular distance from Mizar.
Although the statement has been made that Alcor was not known to the Greeks, there is an old story that it was the Lost Pleiad Electra, which had wandered here from her companions and became Alopex, the Fox; a Latin title was Eques Stellula, the Little Starry Horseman; Eques, the Cavalier, is from the 17th century German astronomer Bayer; while the Horse and his Rider, and, popularly, in England, Jack on the Middle Horse, are well known, Mizar being the horse. The Persian astronomer Al Biruni (973-1048 A.D.) mentioned its importance in the family life of the Arabs on the 18th day of the Syrian month Adar, the March equinox; and a modern story of that same people makes it the infant of the walidan of the three Banat.
More components of the Mizar system were discovered with the advent of the telescope and spectroscopy; a fine, easily-split visual target, Mizar was the first telescopic binary discovered—most probably by Benedetto Castelli who in 1617 asked Galileo Galilei to observe it. Galileo then produced a detailed record of the double star. Later, around 1650, Riccioli wrote of Mizar appearing as a double. The secondary star, Mizar B, has magnitude 4.0 and spectral class A7, and comes within 380 AU of the primary; Mizar A and Mizar B take thousands of years to revolve around each other.
Mizar A was the first spectroscopic binary to be discovered, by Pickering in 1889. Some spectroscopic binaries cannot be visually resolved and are discovered by studying the spectral lines of the suspect system over a long period of time. The two components of Mizar A are both about 35 times as bright as the sun, and revolve around each other in about 20 days 12 hours and 55 minutes. Mizar B was later found to be a spectroscopic binary as well, its components completing an orbital period every six months. In 1996, 107 years after their discovery, the components of the Mizar A binary system were imaged in extremely high resolution using the Navy Prototype Optical Interferometer.


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