Alpha Sagittae (α Sge) is a star in the constellation Sagitta. It also has the traditional name Sham or Alsahm which comes to us from Arabic and means Arrow, the name formally having been applied to the whole constellation. In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... Jump to: navigation, search The J2000. ... Jump to: navigation, search Orion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). ... Sagitta, being Latin for Arrow, is the third-smallest of all constellations (only Equuleus and Crux are smaller). ... 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. ... Jump to: navigation, search The parsec (symbol pc) is a unit of length used in astronomy. ... 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. ... 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, 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. ... In astronomy, many stars are referred to simply by catalogue numbers. ... Jump to: navigation, search 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. ... Jump to: navigation, search Orion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). ... Sagitta, being Latin for Arrow, is the third-smallest of all constellations (only Equuleus and Crux are smaller). ...

α Sge is a yellow giant star of magnitude +4.37 and spectral class G1 II about 475 light years from Earth. It has a luminosity 340 times that of the Sun with a surface temperature of 5400 Kelvin. The star's radius is roughly 20 times solar while its mass is 4 times the solar mass. In science, magnitude refers to the numerical size of something: see orders of magnitude. ... Jump to: navigation, search 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. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ... Jump to: navigation, search // In General Physics In general physics, luminosity (more properly called luminance) is the density of luminous intensity in a given direction. ... Jump to: navigation, search The Sun is the star at the centre of our Solar system. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... Jump to: navigation, search The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... In astronomy, the solar mass is a unit of mass used to express the mass of stars and larger objects such as galaxies. ...

External Link

• Bright Star Catalogue
• Sham