Below there is a list of the least massive known black holes, sorted by increasing mass. The unit of measurement is the solar mass, equivalent to 2.0×1030 kg.
Name | Mass ( M☉) |
Distance ( ly) |
Companion class | Mass determination method | Notes | Refs. |
---|---|---|---|---|---|---|
V723 Monocerotis | 3.04±0.06 | 1,500 | K0III | Spectroscopic radial velocity measurements of companion. | Mass may be underestimated due not accurately measured distance to the companion star.[ clarify] | [1] |
2MASS J05215658+4359220 | 3.3+2.8 −0.7 |
10,000 | K-type (?) giant | Spectroscopic radial velocity measurements of noninteracting companion. | In Milky Way outskirts. | [2] [3] [4] |
GW190425's remnant | 3.4+0.3 −0.1 |
518,600,000 | N/A | Gravitational wave data of neutron star merger from LIGO and Virgo interferometers. | 97% chance of prompt collapse into a black hole immediately after merger. Alternative study suggests collapse 2.5 hours later. | [2] [5] [6] [7] |
NGC 3201-1 | 4.36±0.41 | 15,600 | (see Notes) | Spectroscopic radial velocity measurements of noninteracting companion. | In globular cluster NGC 3201. Companion is 0.8M☉ main sequence turn-off. | [2] [8] |
GRO J1719-24/ GRS 1716−249 |
≥4.9 | 8,500 | K0-5 V | Near-infrared photometry of companion and Eddington flux. | LMXB system. | [2] [9] |
4U 1543-47 | 5.0+2.5 −2.3 |
30,000 ± 3,500 | A2 (V)? | Spectroscopic radial velocity measurements of companion. | SXT system. | [2] [10] |
XTE J1650-500 | ≥5.1 | 8,500 ± 2,300 | K4V | Orbital resonance modeling from QPOs | Transient binary X-ray source | [11] [12] |
GRO J1655-40 | 5.31±0.07 | <5,500 | F6IV | Precision X-ray timing observations from RossiXTE. | LMXB system. | [13] [14] |
GX 339-4 | 5.9±3.6 | 26,000 | N/A | [2] |
Below there is a list of the least massive known black holes, sorted by increasing mass. The unit of measurement is the solar mass, equivalent to 2.0×1030 kg.
Name | Mass ( M☉) |
Distance ( ly) |
Companion class | Mass determination method | Notes | Refs. |
---|---|---|---|---|---|---|
V723 Monocerotis | 3.04±0.06 | 1,500 | K0III | Spectroscopic radial velocity measurements of companion. | Mass may be underestimated due not accurately measured distance to the companion star.[ clarify] | [1] |
2MASS J05215658+4359220 | 3.3+2.8 −0.7 |
10,000 | K-type (?) giant | Spectroscopic radial velocity measurements of noninteracting companion. | In Milky Way outskirts. | [2] [3] [4] |
GW190425's remnant | 3.4+0.3 −0.1 |
518,600,000 | N/A | Gravitational wave data of neutron star merger from LIGO and Virgo interferometers. | 97% chance of prompt collapse into a black hole immediately after merger. Alternative study suggests collapse 2.5 hours later. | [2] [5] [6] [7] |
NGC 3201-1 | 4.36±0.41 | 15,600 | (see Notes) | Spectroscopic radial velocity measurements of noninteracting companion. | In globular cluster NGC 3201. Companion is 0.8M☉ main sequence turn-off. | [2] [8] |
GRO J1719-24/ GRS 1716−249 |
≥4.9 | 8,500 | K0-5 V | Near-infrared photometry of companion and Eddington flux. | LMXB system. | [2] [9] |
4U 1543-47 | 5.0+2.5 −2.3 |
30,000 ± 3,500 | A2 (V)? | Spectroscopic radial velocity measurements of companion. | SXT system. | [2] [10] |
XTE J1650-500 | ≥5.1 | 8,500 ± 2,300 | K4V | Orbital resonance modeling from QPOs | Transient binary X-ray source | [11] [12] |
GRO J1655-40 | 5.31±0.07 | <5,500 | F6IV | Precision X-ray timing observations from RossiXTE. | LMXB system. | [13] [14] |
GX 339-4 | 5.9±3.6 | 26,000 | N/A | [2] |