The members of the RECONS 10 parsec sample as of 2009.0 are shown in
histogram form, based on each object's absolute visual magnitude, Mv.
Both primary stars and companions are included in the counts. Solid
bars represent objects with published trigonometric parallaxes in the
refereed literature larger than 100 milliarcseconds and with errors
less than 10 milliarcseconds. Open bars represent objects suspected
to meet these sample criteria but which are unpublished as of January
1, 2009.
The light blue bar represents white dwarfs that are the leftover cores of stars that have undergone evolution and shed their outer layers. Their Mv values are, in fact, between Mv = 11 and 17, but the precursor stars that produced them had Mv values typically brighter than 5. The blue bars represent stars of spectral types A, F, G, and K. The red bars represent the ubiquitous red dwarfs of spectral type M that dominate the solar neighborhood. Four L dwarfs with measured Mv values are also included. The black bar represents the T dwarfs. The green bar represents planetary companions, all of which are companions to stars in the sample, i.e. none are free-floating objects between the stars. These objects are almost certainly planets, although definitive masses remain elusive in most cases, so it is possible that they are more massive brown dwarfs or stars.
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