Changes

==Star System==

==Star System==

The two stars of the Procyon system orbit each other with an average distance of 14.9 AU, equivalent to the distance of [[Uranus]] from the Sun, although the orbit is eccentric and carries the two stars as close as 9 AU and as far as 21 AU.  The secondary or companion star, Procyon B, isn't visible to the unaided eye and wasn't postulated to exist until 1840, through observances of the irregularities in the proper motion of the Procyon system.  Procyon B was first visually confirmed with a 36 inch refracting telescope in 1896 by John M. Schaeberle<ref>http://www.solstation.com/stars/procyon2.htm</ref>.

The two stars of the Procyon system orbit each other with an average distance of 14.9 AU, equivalent to the distance of [[Uranus]] from the Sun, although the orbit is eccentric and carries the two stars as close as 9 AU and as far as 21 AU.  The secondary or companion star, Procyon B, isn't visible to the unaided eye and wasn't postulated to exist until 1840, through observances of the irregularities in the proper motion of the Procyon system.  Procyon B was first visually confirmed with a 36 inch refracting telescope in 1896 by John M. Schaeberle.<ref>http://www.solstation.com/stars/procyon2.htm</ref>

===Procyon A===

===Procyon A===

Procyon A is the eighth brightest star in the night sky, and with an apparent magnitude of 0.34, can easily be seen in all but the most light polluted skies.  The star itself is a white-yellow, main sequence dwarf of spectral type F5 V-IV.  Procyon is some 1.5 times the mass of the Sun<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000AJ....119.2428G&db_key=AST&high=3ab60d466721564</ref>, and some 1.4 to 2.3 times the diameter.  Procyon A is also 7.5 times as bright as our Sun<ref>http://simbad3.u-strasbg.fr/cgi-bin/cdsbib4?2006AJ....131.1015G</ref>.

Procyon A is the eighth brightest star in the night sky, and with an apparent magnitude of 0.34, can easily be seen in all but the most light polluted skies.  The star itself is a white-yellow, main sequence dwarf of spectral type F5 V-IV.  Procyon is some 1.5 times the mass of the Sun,<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000AJ....119.2428G&db_key=AST&high=3ab60d466721564</ref> and some 1.4 to 2.3 times the diameter.  Procyon A is also 7.5 times as bright as our Sun.<ref>http://simbad3.u-strasbg.fr/cgi-bin/cdsbib4?2006AJ....131.1015G</ref>

The [[metallicity]] of Procyon A is around 1.4 times that of the Sun, based on its abundance of [[iron]].  It is theorized that Procyon A is metal-rich because it was enriched by Procyon B when the latter puffed out its metals-rich outer layers before becoming a [[white dwarf]]<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000PASP..112..827K&db_key=AST&high=38ef9e6de213472</ref>.

The [[metallicity]] of Procyon A is around 1.4 times that of the Sun, based on its abundance of [[iron]].  It is theorized that Procyon A is metal-rich because it was enriched by Procyon B when the latter puffed out its metals-rich outer layers before becoming a [[white dwarf]].<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000PASP..112..827K&db_key=AST&high=38ef9e6de213472</ref>

The star is also a BY Draconis-type [[variable star]].  Although its brightness does change from the point of the observer because of eclipsing by Procyon B, the star varies intrinsically as well.  It has a New Suspect Variable (NVS) designation of NVS 3672.

The star is also a BY Draconis-type [[variable star]].  Although its brightness does change from the point of the observer because of eclipsing by Procyon B, the star varies intrinsically as well.  It has a New Suspect Variable (NVS) designation of NVS 3672.

===Procyon B===

===Procyon B===

Procyon B is a dim white dwarf of spectral class DQZ, A4.  However the close proximity to the much brighter Procyon A has made precise measurements about the star's spectrum difficult.  The star is estimated to be around 15,000 times fainter then its primary.  Procyon B is also only 6/10,000th as luminous as our [[Sun]], and only 2 perfect its diameter.  Because it is a white dwarf, it still has 60 percent of our Sun's mass, having a density estimated to be over two tones per cubic inch<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000AJ....119.2428G&db_key=AST&high=3ab60d466721564</ref>.

Procyon B is a dim white dwarf of spectral class DQZ, A4.  However the close proximity to the much brighter Procyon A has made precise measurements about the star's spectrum difficult.  The star is estimated to be around 15,000 times fainter then its primary.  Procyon B is also only 6/10,000th as luminous as our [[Sun]], and only 2 perfect its diameter.  Because it is a white dwarf, it still has 60 percent of our Sun's mass, having a density estimated to be over two tones per cubic inch.<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000AJ....119.2428G&db_key=AST&high=3ab60d466721564</ref>

===Substellar Companions===

===Substellar Companions===