Changes

Jump to: navigation, search

Kapteyn's Star

15 bytes added, 13:59, December 23, 2009
Grammar fixes
}}
'''Kapteyn's Star''' is one of the closest stars to our solar system[[Solar System]]. The star is noted for its unusual features compared to other local stars, such as its retrograde galactic orbital path, extreme age, and origins outside the galactic plane. The star was first discovered by Jacobus Cornelius Kapteyn (1851-1922) and Robert Thorburn Ayton Innes in 1897,<ref name="sol">http://www.solstation.com/stars/kapteyns.htm</ref> and was found to have the greatest proper motion of any star until the discovery of [[Barnard's Star]].
Kapteyn's Star itself is classified as a M0-1.5V(dwarf) or VI(subdwarf) halo star<ref>http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1997AJ....113..806G</ref>, meaning its origins are from the [[Milky Way|Milky Way's]] [[galactic halo]], a spherical region around the [[galaxy]] containing very old, [[Metallicity|metal-poor]] stars. Because the star is a dim M class dwarf with only 4/1000th of the sun's brightness, it has an apparent magnitude of 8.85, rendering it invisible to the unaided eye . This is despite being located only 12.77 years away, making it the 25th closest star. Kapteyn's Star has only 10.5 percent of the Metallicity of Sol, 29 to 39.3 percent of Sol's mass<ref>http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2004MNRAS.350..575W&db_key=AST&high=41dd40b72e13373</ref>, and less than third (29 to 32 percent) of its diameter<ref name="sol">http://www.solstation.com/stars/kapteyns.htm</ref>. It is also a [[variable star]], and thus is also known by its variable star designation of ''VZ Pictoris''.
Because Kapteyn's Star is so metal-poor (lacking in elements heavier then [[hydrogen]] and [[helium]]), it appears more bluish and dimmer then the typical younger, main sequence M-class dwarf<ref>http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1976ApJ...205..186W</ref>. Due of the lack of metals, it is generally accepted the star was born in an earlier age and/or region such as the galatic halo where few [[supernova]] have released their metals into the surrounding region (supernova being the general source of all elements above helium on the [[periodic table]]).
798
edits