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Sigma Draconis' traditional name is '''Alsafi''', which is derived from the Arabic word ''athafi'' (or ''Athafiyy''), meaning "''the cooking tripods''".  This is in reference to the tripods desert nomads used for cooking in the open-air.<ref>Allen, Richard Hinkley (1963). Star Names, Their Lore and Meaning. New York: Dover. ISBN 0-486-21079-0.</ref>

Sigma Draconis' traditional name is '''Alsafi''', which is derived from the Arabic word ''athafi'' (or ''Athafiyy''), meaning "''the cooking tripods''".  This is in reference to the tripods desert nomads used for cooking in the open-air.<ref>Allen, Richard Hinkley (1963). Star Names, Their Lore and Meaning. New York: Dover. ISBN 0-486-21079-0.</ref>

Sigma Draconis is a orange-red dwarf star on the main sequence of spectral class K0 V.  The star has some 89 percent of our Sun's mass, and some 79 percent of its diameter, but is only 39 percent as luminous.<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001A%26A...367..521P&db_key=AST&data_type=HTML&format=&high=4378fcfeea24447</ref>  The star's [[metallicity]] is only some 56 to 59 percent that of out [[Sun]], based on the abundance of [[iron]].   

Sigma Draconis is an orange-red dwarf star on the main sequence of spectral class K0 V.  The star has some 89 percent of our Sun's mass, and some 79 percent of its diameter, but is only 39 percent as luminous.<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001A%26A...367..521P&db_key=AST&data_type=HTML&format=&high=4378fcfeea24447</ref>  The star's [[metallicity]] is only some 56 to 59 percent that of out [[Sun]], based on the abundance of [[iron]].   

So far all searches using radial velocity techniques, conducted by the Lick Planet Search, to locate substellar companions around Sigma Draconis have failed to find any [[brown dwarf]] or large [[gas giant]] very near to the star.  For an [[terrestrial planet|Earth-like]] world to have liquid water on its surface, the orbit would need to be around 0.62 AU, somewhat less then the orbit of [[Venus]].  At this time such a world is about impossible to detect.

So far all searches using radial velocity techniques, conducted by the Lick Planet Search, to locate substellar companions around Sigma Draconis have failed to find any [[brown dwarf]] or large [[gas giant]] very near to the star.  For an [[terrestrial planet|Earth-like]] world to have liquid water on its surface, the orbit would need to be around 0.62 AU, somewhat less than the orbit of [[Venus]].  At this time such a world is about impossible to detect.

Currently Sigma Draconis is considered a high priority target for the both the future NASA's [[Terrestrial Planet Finder]] and the ESA's Darwin probe when they are launched around 2015.  These probes will search for rocky worlds in the [[habitable zone]] of Sigma Draconis and other stars.

Currently Sigma Draconis is considered a high priority target for the both the future NASA's [[Terrestrial Planet Finder]] and the ESA's Darwin probe when they are launched around 2015.  These probes will search for rocky worlds in the [[habitable zone]] of Sigma Draconis and other stars.