Astronomers think that Algol started off as a detached binary, with both components lying well within their respective Roche lobes. Algol, also known as Beta Persei, is a triple star system located 92.8 light years away in the constellation of Perseus. The brighter (B8-type) star contributes about 92 percent of the light of the system, and the eclipsed star provides less than 8 percent. It appears to blink nearly every 72 hours. The main star is a B8 main-sequence star 3 times as large as our sun and the secondary star is a K2-type subgiant. Using the light curves it is possible to specify the beginning and end of eclipses. Star A is separated from its close companion "B" on average by only 0.062 AUs (a semi-major axis of 0.00218" at a HIPPARCOS distance estimate of 92.8 ly). The first eclipsing binary detected was Algol, β Perseus, also known as the Demon star possibly due to its changing brightness. This type of variable star is known as an eclipsing binary. The secondary component (Aa2) in the Algol system is a magnitude 2.9 K-type star that is separated from the primary star (Aa1) by only 0.062 AU, giving it an orbital period of 2 days, 20 hours, and 49 minutes. Algol (Beta Persei) is the name of a star in the constellation Perseus. Together they rotate around each other. Brightness of the Star. (We now know there is a third star in the Algol system, but it is not involved in the eclipses.) This type of variable star is called an eclipsing binary system, and Algol was the first system of this kind to be discovered. M. ... Algol. Algol is a variable star, meaning it undergoes wide variations in its brightness over time. Fixed Star Algol 25° or 26° Taurus The most evil star in the cosmos. This animation represents an Algol-type eclipsing binary. Algol variables or Algol-type binaries are a class of eclipsing binary stars that are related to the prototype member of this class, β Persei (Beta Persei, Algol) from an evolutionary point of view.. Algol, The "Demon Star" Algol, the second brightest star in the northern constellation Perseus, is the finest example of an eclipsing variable star. Algol is a trinary star system, containing 3 stars, Algol A, a star of spectral type B (blue in color), Algol B is K-type (orange), and Algol C is A-type (blue-white). In addition, Algol is also a prototype for the Algol variable class of stars. Algol is the most notorious fixed star our sky has to offer, yet it can also bestow unparalleled protection and avenge those who have been victimized by unjust deeds. Algol is a trinary star system, containing 3 stars, Algol A, a star of spectral type B (blue in color), Algol B is K-type (orange), and Algol C is A-type (blue-white). The blinking is cause by a binary star eclipsing Algol nearly every 3 days. It is ane o the best kent eclipsin binaries , the first such starn tae be discovered, an an aa ane o the first (non- nova ) variable starns tae be discovered. The top two, Mirfak (Alpha) and Algol (Beta) have proper names, and then the list stops until we arrive at number 10, a fourth magnitude star called "Atik" and Bayer's "Omicron" star. Algol wins notoriety for its wild swings in brightness, which recur with clock-like precision. Between eclipses the light remains almost constant. Merikanto / Wikipedia CC BY-SA 4.0. The system contains a third star … This means they can be predicted so that we know when to watch for them. I’m … Algol is an eclipsing binary star system 93 light-years away as determined by the Hipparcos satellite. Universal Times and dates of Algol's fadings are available online in the companion article, "The Minima of Algol.". 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