Mu1 Bootis, Mu2 Bootis - AlkaluropsMu Bootis is a magnitude 4.31 star in Bootes, the Herdsman, and is also called by the jaw-breaking name Alkalurops. "Alkalurops" actually derives from Greek, and means "club." But the original name, going from Greek to Arabic to Latin to Greek to Latin and thence made to sound Arabic, came to mean "shepherd's staff," more fitting for the Herdsman.ComponentsAlkalurops is a wonderful triple star. Lying 1.8' away from μ Boo A is a companion of magnitude 6.50, technically visible to the naked eye. This easily-visible companion (μ Boo BC) is clearly double, and consists of a pair of sunlike class G1 stars that average 1.5" apart. The brighter star (μ Boo B), at magnitude 6.98, has twice the Sun's luminosity, whereas the fainter companion (μ Boo C, magnitude 7.63) is almost a clone of the Sun.The BC pair orbit each other every 260 years at an average distance of 54 AU. The pair lies at least 4000 AU distant from the two-solar mass primary (μ Boo A), and take at least 125,000 years to make a full orbit. From Alkalurops A, the BC pair would appear as a brilliant, starlike "double sun" 100 times brighter than Venus, separated by up to a degree.Properties and EvolutionMeanwhile, the system's primary A component is a mid-temperature (7195 K) main-sequence star of class F0. At a distance of 120 light years, its luminosity is 20 suns, which makes it too bright for its class. This implies that it is either starting to evolve off the main sequence, or that it too is double. Its spectrum suggests an unresolved companion with a period near 300 days, making the system quadruple. The primary star may also be a subtle variable.Physically, Alkalurops A lies near the transition point where stars hotter than our Sun fuse hydrogen to helium through the C-N-O cycle (in which carbon, nitrogen, and oxygen are used as nuclear catalysts), rather than to helium directly. They also have no circulating, convective outer layers, and tend to rotate much faster; Alkalurops spins at least 40 times faster than the Sun.[Adapted from STARS by Jim Kaler, Professor Emeritus of Astronomy, University of Illinois]