Star Type | # Density (pc^-3) | Fraction of stars | Reference | Comments |
O stars | 4.4e-8(±2.0e-8)[#1] | ~5e-7 (1 in ~2,000,000) |
EEM | #1: cross-referenced GOSS (Sota+2014) catalog w/van Leeuwen(2007) & Gaia DR1 TGAS. N=5 O-type stars w/ plx > 3.33 mas (d<300pc): zeta Oph, delta Ori, zeta Ori, 15 Mon, HD 37737. Parallaxes very poor beyond that for most stars. |
B stars | 3.2e-5(±4.7e-6) [#1] | 3.9e-4 (1 in 2600) |
EEM | #1: calc from HIP2 (B-type, Mv < 2, plx/e(plx)>8, d<70pc, N=46) |
A stars | 4.9e-4(±6.6e-5) [#1] | 6.0e-3 (1 in 170) |
EEM | #1: calc from HIP2 (A-type, Mv<4, plx/e(plx)>8, d<30pc, N=55) |
F stars (all lum classes) |
0.0025(±0.0003)[#1] | 0.031 (1 in 33) |
EEM | #1: see http://www.pas.rochester.edu/~emamajek/Fstars_dens.txt |
F dwarfs | 0.0024(±0.0003)[#1] | 0.029 (1 in 34) |
EEM | #1: see http://www.pas.rochester.edu/~emamajek/Fstars_dens.txt |
G stars (all lum class) |
0.0048(±0.0011) [#1] | 0.059 (1 in 17) |
EEM | #1: calc from RECONS (10pc, N=20, likely complete) |
G dwarfs | 0.0033(±0.0004) [#1] 0.0038(±0.0010) [#2] 0.0037(±0.0013) [#3] |
0.041 (1 in 25) |
EEM | #1: calc from Mamajek+08 (16pc, N=57, likely complete) #2: calc from Mamajek+08 (10pc, N=16, likely complete) #3: calc from Kirkpatrick+12 (8pc, N=8, complete) Note: del Pav (6.1pc) classified G8IV, but within 0.8 mag of MS (so "dwarf") |
K dwarfs | 0.0105(±0.0016) [#1] 0.0135(±0.0025) [#2] 0.0153(±0.0054) [#3] |
0.129 (1 in 7.8) |
EEM | #1: calc from RECONS (10pc, N=44, likely complete) #2: calc from Kirkpatrick+12 (8pc, N=29, likely complete) #3: calc from Kirkpatrick+12 (5pc, N=8, likely complete) |
M dwarfs | 0.0592(±0.0038) [#1] 0.0859(±0.0086) [#2] 0.0917(±0.0132) [#3] |
0.725 (1 in 1.38) |
EEM | #1: calc from RECONS (10pc, N=248, likely incomplete) #2: calc from Kirkpatrick+12 (6.527pc, N=100) #3: calc from Kirkpatrick+12 (5pc, N=48, likely complete) |
white dwarfs (e.g. DA, DB, DC, DQ, DZ, etc.) |
0.0048(±0.0011)[#1] 0.0051(±0.0015)[#2] 0.0048(±0.0005)[#3] |
0.059 (1 in 17) |
EEM | #1: calc from RECONS 10 pc sample (N=20 as of 2012.0) #2: calc from Kirkpatrick+2012 8 pc sample (N=11) #3: Holberg+ 2016 25 pc sample (N=232) |
"Evolved stars" | 8.8e-4 | 0.011 (1 in 93) |
EEM | includes stars just leaving main sequence, subgiants, giants, calc using HIP2 for Mv > 1 mag away from Wright 2004 main sequence, Mv < 4.5 (d < 35 pc; N=158) |
"Red Giants" | 2.7e-4(±4.9e-5)[#1] | 3.3e-3 (1 in 300) |
EEM | #1: G/K/M giants only, N=31 w/i d<30pc (using van Leeuwen 2007 HIP parallaxes) |
all stars OBAFGKM *s + WDs ignoring NSs & BHs |
0.0816(±0.0044)[#1] 0.0936(±0.0134)[#2] 0.0984(±0.0068)[#3] |
1 | EEM | #1: calc from RECONS 10 pc sample (N=342) #2: calc from Kirkpatrick+2012 5 pc sample (N=49) #3: calc from Kirkpatrick+2012 8 pc sample (N=211) |
Star Type | # Density (pc^-3) | Fraction of stars | Reference | Comments |