Sigma Canis Majoris (σ CMa / σ Canis Majoris) is a star in the constellation Canis Major. The cosmic distance ladder (also known as the Extragalactic Distance Scale) is the succession of methods by which astronomers determine the Distances to celestial A light-year or light year (symbol ly) is a unit of Length, equal to just under ten trillion Kilometres As defined by History The first direct measurements of an object at interstellar distances were undertaken by German Astronomer Friedrich Wilhelm Bessel in 1838 In Astronomy, stellar classification is a classification of Stars based initially on photospheric temperature and its associated Spectral characteristics A star catalogue, or star catalog, is an Astronomical catalogue that lists Stars In Astronomy, many stars are referred to simply by catalogue The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars or Yale Bright Star Catalogue, is a Star catalogue that lists of all stars of The Henry Draper Catalogue ( HD) is an Astronomical Star catalogue published between 1918 and 1924 giving Spectroscopic classifications In Astronomy, Durchmusterung or Bonner Durchmusterung ( BD) is the usual name for three comprehensive astrometric Star catalogues The Catalogue of Fundamental Stars is a series of six astrometric catalogues of high precision positional data for a small selection of stars to define a celestial reference The Hipparcos and Tycho Catalogues (Tycho-1 are the primary products of the European Space Agency 's astrometric mission Hipparcos. The Smithsonian Astrophysical Observatory Star Catalog is an astrometric Star catalogue. A star catalogue, or star catalog, is an Astronomical catalogue that lists Stars In Astronomy, many stars are referred to simply by catalogue A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth In common usage a constellation is a group of celestial bodies that are connected together in some arrangement typically stars to form a visible figure or picture Canis Major ( greater Dog) is one of the 88 modern Constellations and was also in Ptolemy 's list of 48 constellations It is approximately 1220 light years from Earth. A light-year or light year (symbol ly) is a unit of Length, equal to just under ten trillion Kilometres As defined by EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001

σ Canis Majoris is an orange K-type supergiant with a mean apparent magnitude of +3. In Astronomy, stellar classification is a classification of Stars based initially on photospheric temperature and its associated Spectral characteristics Supergiants are among the most massive Stars In the Hertzsprung-Russell diagram they occupy the top region of the diagram The apparent magnitude ( m) of a celestial body is a measure of its Brightness as seen by an observer on Earth, normalized to the value 49. It is classified as an irregular variable star and its brightness varies from magnitude +3. An irregular variable is a type of Variable star in which variations in brightness show no regular Periodicity. For the astronomical object see Variable star. Variable Star is a 2006 novel written by Spider Robinson 43 to +3. 51.