Alpha Andromedae (α And / α Andromedae) is the brightest star in the Andromeda constellation, which is located immediately northwest of Pegasus. It also has the traditional names Alpheratz and Sirrah (or Sirah). As a connecting star to Pegasus, it is also known as Delta Pegasi (δ Peg), though this name is no longer used (another such doubly-named connecting star is Beta Tauri). It is located 97 light years from Earth. In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... Orion is a remarkable constellation, visible from most places on the globe at one time or another during the year. ... Andromeda is a constellation named for the princess Andromeda (which is Greek for Ruler over men), a character in Greek mythology. ... Right ascension (RA; symbol α: Greek letter alpha) is the astronomical term for one of the two coordinates of a point on the celestial sphere when using the equatorial coordinate system. ... In astronomy, declination (dec) is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. ... // Headline text HEY!! HOW ARE YOU ALL?? Its nice of you to come read this page. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequently refined in terms of other characteristics. ... Shanil Davendra Singh rules 4 life! ... Shanil Davendra Singh rules 4 life! ... Most stars are of almost constant luminosity. ... Alpha2 Canum Venaticorum variables are main sequence variable stars of spectral class B8p to A7p. ... This article does not cite its references or sources. ... Radial velocity is the velocity of an object in the direction of the line of sight. ... kilometre per second is an SI derived unit of both speed (scalar) and velocity (vector), signified by the symbol km/s or km s-1. ... The proper motion of a star is the motion of the position of the star in the sky (the change in direction in which we see it, as opposed to the radial velocity) after eliminating the improper motions of the stars, which affect their measured coordinates but are not real... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... Parallax (Greek: παραλλαγή (parallagé) = alteration) is the change of angular position of two stationary points relative to each other as seen by an observer, due to the motion of an observer. ... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... The distance between two points is the length of a straight line segment between them. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ... The parsec (symbol pc) is a unit of length used in astronomy. ... In astronomy, absolute magnitude is the apparent magnitude, m, an object would have if it were at a standard luminosity distance away from us. ... Mass is a property of a physical object that quantifies the amount of matter it contains. ... In astronomy, the solar mass is a unit of mass used to express the mass of stars and larger objects such as galaxies. ... RADIUS (Remote Authentication Dial In User Service) is an AAA (authentication, authorization and accounting) protocol for applications such as network access or IP mobility. ... In astronomy, the solar radius is a unit of length used to express the size of stars and larger objects such as galaxies. ... Luminosity has different meanings in several different fields of science. ... The solar luminosity, , is a unit of luminosity (power emitted in the form of photons) conventionally used by astronomers to give the luminosities of stars. ... Temperature is also the name of a song by Sean Paul. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... In astronomy, the metallicity of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium. ... Rotation of a plane, seen as the rotation of the terrain relative to the plane (exposure time 1. ... The Pleiades star cluster A star is a massive body of plasma in outer space that is currently producing or has produced energy through nuclear fusion. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... The Henry Draper Catalogue is an astronomy catalogue with astrometric and spectroscopic data about more than 225,000 stars. ... The Smithsonian Astrophysical Observatory (SAO) is a research institute of the Smithsonian Institution headquartered in Cambridge, Massachusetts, where it is joined with the Harvard College Observatory (HCO) to form the Harvard-Smithsonian Center for Astrophysics (CfA). ... In astronomy, many stars are referred to simply by catalogue numbers. ... Andromeda is a constellation named for the princess Andromeda (which is Greek for Ruler over men), a character in Greek mythology. ... Orion is a remarkable constellation, visible from most places on the globe at one time or another during the year. ... Pegasus is a northern constellation, named after the mythological Pegasus. ... Elnath (or El Nath), is a star in the constellation Taurus. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ...

A magnitude 2.2 blue-white binary, Alpheratz is composed of two close-orbiting stars that can be distinguished only by careful spectroscopic analysis. The larger of the two is about ten times the size of the smaller, and they orbit each other with a period of 96.7 days. Classified as spectral-type B8, the pair is about 200 times brighter than the Sun, and has a surface temperature of about 13,000 kelvins. The Sun is the star at the center of Earths solar system. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ...

The larger of the two stars comprising Alpheratz is the brightest known of an odd group of stars known as "mercury-manganese stars." It displays an anomalously high abundance of mercury, gallium, manganese, and europium in its atmosphere, and an unusually low concentration of other elements. These anomalies are believed to be the result of separation of elements due to the inward pull of the star's gravity. It is also classified as an Alpha2 Canum Venaticorum type variable star and its brightness varies from magnitude +2.02 to +2.06 with a period of 23.19 hours. General Name, Symbol, Number mercury, Hg, 80 Chemical series transition metals Group, Period, Block 12, 6, d Appearance silvery white Atomic mass 200. ... General Name, Symbol, Number gallium, Ga, 31 Chemical series poor metals Group, Period, Block 13, 4, p Appearance silvery white   Atomic mass 69. ... General Name, Symbol, Number manganese, Mn, 25 Chemical series transition metals Group, Period, Block 7, 4, d Appearance silvery metallic Atomic mass 54. ... General Name, Symbol, Number europium, Eu, 63 Chemical series lanthanides Group, Period, Block ?, 6, f Appearance silvery white Atomic mass 151. ... Alpha2 Canum Venaticorum variables are main sequence variable stars of spectral class B8p to A7p. ... Most stars are of almost constant luminosity. ...

The names Alpheratz and Sirrah both derive from the original Arabic name, صرة الفرس şirra^t al-faras, "navel of the steed".