# List of O-type stars

This is a list of O-type stars by their distance from Earth.

## List
### Milky Way galaxy

| Star system←← | Median distance (ly) | Stars in system | Spectral type | Apparent magnitude (V) | Comments and references |
| Zeta Ophiuchi | 440 ± 40 | 1 | O9.5 V | 2.56 – 2.58 | The closest O-type star to Earth. |
| Zeta Puppis (Naos) | 1,080 ± 40 | 1 | O4If(n)p | 2.24 - 2.26 | |
| Gamma² Velorum (Suhail al Muhlif/Regor) | 1096+26 −23 | 2 | O7.5III | 1.83 | Has a Wolf-Rayet Companion. |
| Mintaka A (Delta Orionis, 34 Orionis) | 1,200 | 3 | O9.5II | 2.5 | |
| Alnitak (Zeta Orionis, 50 Orionis) | 1,260 ± 180 | 3 | O9.5Iab | 1.77 | |
| Sigma Orionis A | 1263±4.3 | 2 | O9.5V | 4.07 | |
| Meissa A (Lambda Orionis) | 1260±200 | 1 | O8 III((f)) | 3.7 | |
| AE Aurigae | 1,320 ± 40 | 1 | O9.5V | 5.96 | |
| Xi Persei (Menkib) | 1340±65 | 1 | O7.5III(n)((f)) | 4.04 | |
| Theta¹ Orionis C1 | 1340±65 | 1 | O6Vp | 5.13 | |
| Iota Orionis (Haytsa) | 1343+45.6 −42.3 | 3 | O9 III | 2.77 | |
| 10 Lacertae | 1,800±103 | 1 | O9V | 4.880 | |
| Mu Columbae | 1,894±111 | 1 | O9.5 V | 5.18 | |
| HD 186924 | 2000 | 1 | O6fp | | It is the central star of NGC 6826 Planetary Nebula. |
| HD 49798 | 2120.02 | 1 | sdO6p | 8.287 | |
| Delta Circini | 2,300 ± 200 | 1 | O7.5III(f) | 5.09 | |
| S Monocerotis (15 Monocerotis) | 2,300 ± 200 | 3 | O7V((f))zvar[4] + O9.5Vn | | |
| Lambda Cephei | 3098.5 | 1 | O6.5If(n)p | +5.050 | |
| Mu Normae | 3,260 | 1 | O9.7Iab | 4.91 | |
| HD 35914 | 3,600 | 1 | O7fp | | It is the central star of IC 418 Planetary Nebula. |
| UW Canis Majoris | 3,800 | 2 | O7.5-8Iabf + O9.7Ib | 4.95 | |
| 19 Cephei | 3,913.88 | 1 | O9Ib | 5.08 | |
| HD 54879 | 4100 ± 200 | 1 | O9.7V | 7.65 | |
| HD 164492 A | 4100 ± 200 | 1 | O7.5III | | |
| 9 Sagittarii | 4,100 ± 400 | 1 | O4V((f))z | 5.97 | |
| 15 Sagittarii | 4,200±650 | 1 | O9.7 Iab | 5.37 | |
| HD 149404 (V918 Scorpii) | 4,300 ± 400 | 2 | O7.5I(f) + ON9.7I | 5.42 - 5.50 | |
| Tau Canis Majoris | 5,120.66 | 3 | O9II | 4.40 | |
| 4U 1700-37 (V884 Scorpii) | 5,200 ± 200 | 1 | O6Iafcp | 6.51 | |
| Plaskett's Star (V640 Monocerotis) | 5,245 | 2 | O8I + O7.5III | 6.06 | |
| Cygnus OB2-8A | 5,400 ± 200 | 1 | O6If + O5.5III(f) | 9.06 | |
| BD+43 3654 | 5,400 ± 300 | 1 | O4If | 10.06 | |
| Alpha Camelopardalis | 6,000 | 1 | O9Ia | 4.29 | |
| WR 133 (V1676 Cyg) | 6,100 ± 300 | 2 | O9I | 6.75 - 6.84 | Has a Wolf-Rayet Companion. |
| HD 59088 | 6,500 | 1 | O(H)6f | | It is the central star of NGC 2392 Planetary Nebula. |
| WR 25 (HD 93162) | 6,500 | 2 | O2.5If*/WN6 + OB | 8.80 | |
| Pismis 24-1 (HD 319718) | 6,500 | 2 | O3.5If*+O4III(f+) | | |
| HD 151804 (V973 Scorpii) | 7,000 | 1 | O8 Iaf | 5.22 - 5.28 | |
| HD 138403 | 7175.44 | 1 | O8(f)ep | | It is the central star of Hen 2-131 Planetary Nebula. |
| Cygnus X-1 | 7,300 ± 200 | 2 | O9.7Iab | 8.95 | |
| Theta Muscae | 7,400 | 4 | O6/7V + O9.5/B0Iab+O9III | 5.53 | Has a Wolf-Rayet Companion. |
| Eta Carinae (Eta Argus) | 7,500 | 2 | O | −1.0 to ~7.6 | part of Trumpler 16 in the Carina Nebula. |
| HD 93129 | 7,501.6 | 1 | O2If*+O3.5 V((f))z | 6.90 | |
| QZ Carinae (HD 93206) | 7,501.6 | 4 | O9.7I+O8III+O9V | 6.24 | |
| HD 93205 (V560 Carinae) | 7,600 ± 400 | 2 | O3.5Vf + O8V | 7.75 | |
| LSS 4067 (CD−38°11748) | 9,500–12,700 | 1 | O4.5Ifpe | 11.44 | |
| BD+60°2522 | 9,800 ± 400 | 1 | O6.5(f)(n)p | 8.67 | |
| HD 93403 | 10,000 | 1 | O5.5III(fc)var | 7.272 | |
| WR 20a | 14,000 ± 1,000 | 2 | O3If*/WN6 + O3If*/WN6 | 13.28 | |
| GCIRS 16SW | 20,000 | 1 | Ofpe/WN9 | | |
| GCIRS 8* | 20,000 | 1 | O5 | | |
| V1936 Aquilae | 20,000 | 1 | O4I | 15.1 | |
| Westerhout 51-57 | 20,000 | 1 | O4V | | Member of Westerhout 51. |
| MTT 68 | 24,787.88 | 1 | O2If* | 14.72 | |
| WR 42e (2MASS J11144550-115001) | 25,000 | 1 | O3If*/WN6 | 14.53 | |
| WR 102ka (Peony star) | 26,000 | 2 | Ofpe/WN9 | | |
| Westerhout 49-2 | 36,200 | 1 | O2-3.5If* | | |

### Magellanic Clouds

The Large Magellanic Cloud (LMC) is around 163 kly distant and the Small Magellanic Cloud (SMC) is around 204 kly distant
| Host galaxy | Star system | Median distance (ly) | Stars in system | Spectral type | Apparent magnitude (V) | Comments and references |
| LMC | R136b | 163,000 | 1 | O4If | 13.24 | |
| LMC | LH 54-425 | 163,000 | 2 | O3V + O5V | 13.13 | |
| LMC | HD 269810 | 163,000 | 1 | O2III(f*) | 12.22 | |
| LMC | Melnick 42 | 163,000 | 1 | O2If* | 12.78 | |
| LMC | BI 253 | 164,000 | 1 | O2V-III(n)((f*)) | 13.76 | |
| LMC | VFTS 243 (2MASS J05380840-6909190) | 164,000 | 1 | O7V(n)((f)) | 15.26 | Has a Known Black Hole Companion |
| LMC | VFTS 102 | 164,000 | 1 | O9:Vnnne | 15.806 | |
| LMC | HD 97950 | 164,000 | 1 | O | | |
| SMC | SMC AB7 | 197,000 | 2 | O6I(f) | 13.016 | |
| SMC | SMC AB8 | 197,000 | 2 | O4V | 12.83 | |
| SMC | HD 5980 | 200,000 | 3 | LBV + WN4 + OI | 8.8 - 11.9 | |

### Andromeda Galaxy and Triangulum Galaxy

The Andromeda Galaxy (M31) is 2.5 Mly distant and the Triangulum Galaxy is around 3.2 Mly distant
| Host galaxy | Star system | Median distance (ly) | Stars in system | Spectral type | Apparent magnitude (V) | Comments and references |
| Triangulum | [BMS2003] 867 | 2,700,000 | 2 | O4Iab+O4Ia | | |
| Triangulum | M33-013406.63 (B416/UIT301) | 3,000,000 | 1 | O9.5Ia | | |

### Other Galaxies

| Host Galaxy | Star system | Median distance (ly) | Stars in system | Spectral type | Apparent magnitude (V) | Comments and references |
| IC 3418 | SDSS J1229+1122 | 550,000,000 | 1 | O | 22.85 | |