OGLE-2011-BLG-0462

OGLE-2011-BLG-462

Animated astrometric observations of the gravitational microlensing of OGLE-2011-BLG-0462/MOA-2011-BLG-191
Observation data Epoch 2455874.50236 (2011-11-09.00 UT)       Equinox 2455874.50236 (2011-11-09.00 UT)
Constellation	Sagittarius
Right ascension	17h 51m 40.15s [1]
Declination	−29° 53′ 26.2″ [1]
Astrometry
Radial velocity (Rv)	134.0 [1] km/s
Proper motion (μ)	RA: −2.210 mas/yr [2] Dec.: −3.533 mas/yr [2]
Distance	5,000±490  ly (1,520±150  pc) [2]
Details
Mass	7.15±0.83 [2]   M☉
Radius	21.1±2.5 [3]   km
Other designations
MOA-2011-BLG-191
Database references
SIMBAD	data

OGLE-2011-BLG-0462, also known as MOA-2011-BLG-191, is a stellar-mass black hole isolated in interstellar space. OGLE-2011-BLG-0462 lies at a distance of 1,720 parsecs (5,610 light years) in the direction of the galactic bulge in the constellation Sagittarius. The black hole has a mass of about 7.15  M_☉. ^[4] OGLE-2011-BLG-0462 is the first truly isolated black hole which has been confirmed. ^{[5] [6] [7]}

Discovery

OGLE-2011-BLG-0462 was discovered by the OGLE survey through microlensing when it passed in front of a background star that was 20,000 light years away from Earth. The black hole's gravity bent the star's light, causing a sharp spike in brightness that was detected by the Hubble Space Telescope. It took six years to confirm the existence of OGLE-2011-BLG-0462. Its initial kick velocity has been estimated to have an upper limit of 100 km/s. ^{[8] [9]} No significant X-ray emission has been detected from gas accreting onto the black hole indicating that it is truly isolated. ^[10]

References

1. Bensby, T.; et al. (2017). "Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars. VI. Age and abundance structure of the stellar populations in the central sub-KPC of the Milky Way". Astronomy and Astrophysics. 605: A89. arXiv: 1702.02971 . Bibcode:2017A&A...605A..89B. doi:10.1051/0004-6361/201730560.
2. Sahu, Kailash C.; Anderson, Jay; Casertano, Stefano; Bond, Howard E.; Dominik, Martin; Calamida, Annalisa; Bellini, Andrea; Brown, Thomas M.; Ferguson, Henry C.; Rejkuba, Marina (2025-04-11). "OGLE-2011-BLG-0462: An Isolated Stellar-mass Black Hole Confirmed Using New HST Astrometry and Updated Photometry". The Astrophysical Journal. 983 (2): 104. arXiv: 2503.07820 . doi: 10.3847/1538-4357/adbe6e . ISSN   0004-637X.
3. "Schwarzschild Radius Calculator". hexacalculator. Retrieved 2025-04-11. Radius calculated using the mass.
4. Lam, Casey Y.; Lu, Jessica R. (2023-10-01). "A Reanalysis of the Isolated Black Hole Candidate OGLE-2011-BLG-0462/MOA-2011-BLG-191". The Astrophysical Journal. 955 (2): 116. arXiv: 2308.03302 . Bibcode:2023ApJ...955..116L. doi: 10.3847/1538-4357/aced4a . ISSN   0004-637X.
5. Lam, Casey Y.; Lu, Jessica R.; Udalski, Andrzej; et al. (2022). ""An Isolated Mass-gap Black Hole or Neutron Star Detected with Astrometric Microlensing"". The Astrophysical Journal Letters. 933 (1): L23. arXiv: 2202.01903 . Bibcode:2022ApJ...933L..23L. doi: 10.3847/2041-8213/ac7442 .
6. Sahu, Kailash C.; Anderson, Jay; Casertano, Stefano; Bond, Howard E.; Udalski, Andrzej; Dominik, Martin; Calamida, Annalisa; Bellini, Andrea; Brown, Thomas M.; Rejkuba, Marina; Bajaj, Varun (2022-01-01). "An Isolated Stellar-mass Black Hole Detected through Astrometric Microlensing". The Astrophysical Journal. 933 (1): 83. arXiv: 2201.13296 . Bibcode:2022ApJ...933...83S. doi: 10.3847/1538-4357/ac739e . S2CID   246430448.
7. "2011-BLG-0462". ogle.astrouw.edu.pl. Retrieved 2022-06-29.
8. Panjkov, Sonja (2023-01-27). "The Peculiar Nature of Black Hole Birth Kicks". astrobites. Retrieved 2023-01-28.
9. Andrews, Jeff J.; Kalogera, Vicky (2022-05-01). "Constraining Black Hole Natal Kicks with Astrometric Microlensing". The Astrophysical Journal. 930 (2): 159. arXiv: 2203.15156 . Bibcode:2022ApJ...930..159A. doi: 10.3847/1538-4357/ac66d6 . ISSN   0004-637X. S2CID   247778998.
10. Mereghetti, Sandro; Sidoli, Lara; Ponti, Gabriele; Treves, Aldo (2022-06-01). "X-Ray Observations of the Isolated Black Hole Candidate OGLE-2011-BLG-0462 and Other Collapsed Objects Discovered through Gravitational Microlensing". The Astrophysical Journal. 934 (1): 62. arXiv: 2206.07480 . Bibcode:2022ApJ...934...62M. doi: 10.3847/1538-4357/ac7965 . S2CID   249674753.