Very few such halo stars are located near our solar system, with such stars accounting for only 0.1 to 0.2 percent of all stars that are near the sun. Kapteyn's Star is believed to be the closest of these. The star is a member of a local cluster of halo stars that is very thinly spread out over a distance of some 6,500 to 9,800 light-years stretching towards the galactic halo<ref>http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1996AJ....112.2661E</ref>. Kapteyn's Star is unusual because most such stars lie far above or below the galactic plane. Like other halo stars, Kapteyn's Star does have an extremely elliptical galactic orbit and is believed to be among the oldest star's in the galaxy and the region around it, estimated to be some 10 billion years old or older. | Very few such halo stars are located near our solar system, with such stars accounting for only 0.1 to 0.2 percent of all stars that are near the sun. Kapteyn's Star is believed to be the closest of these. The star is a member of a local cluster of halo stars that is very thinly spread out over a distance of some 6,500 to 9,800 light-years stretching towards the galactic halo<ref>http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1996AJ....112.2661E</ref>. Kapteyn's Star is unusual because most such stars lie far above or below the galactic plane. Like other halo stars, Kapteyn's Star does have an extremely elliptical galactic orbit and is believed to be among the oldest star's in the galaxy and the region around it, estimated to be some 10 billion years old or older. |