Epsilon Cassiopeiae (ε Cas / ε Cassiopeiae) is a star system in the constellation Cassiopeia. It is approximately 441 light years from Earth. It has the traditional name Segin and was also named Navi ("Ivan," backwards) after Virgil Ivan "Gus" Grissom, the United States' second astronaut. In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... -1... Cassiopeia is a northern constellation which greek mythology considered to represent a vain queen. ... 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. ... 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. ... A star system or stellar system is a group of stars (and possibly smaller bodies such as planets or asteroids) that orbit one another (systems with planetary bodies orbiting stars, are referred to as solar systems or planetary systems). ... -1... Cassiopeia is a northern constellation which greek mythology considered to represent a vain queen. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ... Jump to: navigation, search Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third-closest planet to the Sun. ... Gus Grissom in his Mercury spacesuit Virgil Ivan Gus Grissom (April 3, 1926 – January 27, 1967) was a U.S. Air Force pilot who became one of the first American astronauts and one of the first to die in the U.S. space program. ... U.S. Space Shuttle astronaut Bruce McCandless II using a manned maneuvering unit (MMU) outside the Challenger in 1984. ...

It is a single, blue star with a luminosity 720 times that of the Sun. The Sun is the star at the centre of our Solar system. ...