Alderamin is the proper name of the star α Cephei in the constellation of Cepheus. Alderamin is a fairly sun-like star, albeit somewhat hotter and more massive. It appears to be nearing the end of its life as a main sequence star, and may begin fusing helium as it swells into a red giant or perhaps a subgiant. Alderamin is noted for having an unusually fast rotation, although the effects of this rotation are not well understood. In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... A Julian epoch is an epoch that is based on Julian years of exactly 365. ... 2000 is a leap year starting on Saturday of the Gregorian calendar. ... Most stars are of nearly constant luminosity. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequenly refined in terms of other characteristics. ... 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. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ... This article is about the unit of length. ... The apparent magnitude (m) of a star, planet or other heavenly body is a measure of its apparent brightness; that is, the amount of light received from the object. ... In astronomy, the solar mass is a unit of mass used to express the mass of stars and larger objects such as galaxies. ... In astronomy, the solar radius is a unit of length used to express the size of stars and larger objects such as galaxies. ... In astronomy, absolute magnitude is the apparent magnitude, m, an object would have if it were at a standardized distance away. ... In physics, luminosity is the density of luminous intensity in a given direction. ... 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. ... The historical temperature record shows the fluctuations of the temperature of the atmosphere and the oceans throughout history, and in particular since 1850. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... The Pleiades star cluster A star is any massive gaseous body in outer space just like the Sun. ... Orion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). ... The Boast of Cassiopeia is a story from Greek mythology, associated with Perseus. ... A Sun is the star at the centre of a solar system. ... Hertzsprung-Russell diagram The main sequence of the Hertzsprung-Russell diagram is the curve where the majority of stars are located in this diagram. ... General Name, Symbol, Number Helium, He, 2 Atomic weight 4. ... According to the Hertzsprung-Russell diagram, a red giant is a large non-main sequence star of stellar classification K or M; so-named because of the reddish appearance of the cooler giants. Examples include Aldebaran and Arcturus. ...

The name Alderamin is a contraction of the Arabic phrase الذراع اليمن að-ðirā‘ al-yaman "the right arm", with the first definite article transliterated literally as al, as is often the case with Arabic star names.