PSR J0952–0607
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Sextans |
| Right ascension | 09h 52m 08.319s |
| Declination | −06° 07′ 23.49″ |
| Characteristics | |
| Spectral type | Pulsar |
| Apparent magnitude (i) | 22.0–24.4 |
| Astrometry | |
| Distance | 970+1160 −530 pc or 1740+1570 −820 pc or 6260+360 −400 (optical) pc |
| Details | |
| PSR J0952–0607 A | |
| Mass | 2.35±0.17 M☉ |
| Radius | 12.245+0.685 −0.315 km |
| Rotation | 1.41379836 ms |
| Age | 4.9 Gyr |
| PSR J0952–0607 B | |
| Mass | 0.032±0.002 M☉ |
| Luminosity | 9.96+1.20 −1.12 L☉ |
| Temperature | 3085+85 −80 K |
| Metallicity [Fe/H] | –0.5 dex |
| Orbit | |
| Primary | PSR J0952–0607 A |
| Companion | PSR J0952–0607 B |
| Period (P) | 0.267461035 d (6.41906484 h) |
| Semi-major axis (a) | 1600000 km |
| Eccentricity (e) | <0.004 |
| Inclination (i) | 59.8+2.0 −1.9° |
| Semi-amplitude (K2) (secondary) | 376.1±5.1 km/s |
| Other designations | |
| PSR J0952–0607, 4FGL J0952.1–0607 | |
| Database references | |
| SIMBAD | data |
PSR J0952–0607 is a massive millisecond pulsar in a binary system, located between 3,200–5,700 light-years (970–1,740 pc) from Earth in the constellation Sextans. As of 2022, it holds the record for being the most massive neutron star known, with a mass 2.35±0.17 times that of the Sun—potentially close to the Tolman–Oppenheimer–Volkoff mass upper limit for neutron stars. The pulsar rotates at a frequency of 707 Hz (a period of 1.41 ms), making it the second-fastest-spinning pulsar known, and the fastest-spinning pulsar known within the Milky Way.
PSR J0952–0607 was discovered by the Low-Frequency Array (LOFAR) radio telescope during a search for pulsars in 2016. It is classified as a black widow pulsar, a type of pulsar harboring a closely-orbiting substellar-mass companion that is being ablated by the pulsar's intense high-energy solar winds and gamma-ray emissions. The pulsar's high-energy emissions have been detected in gamma-ray and X-ray wavelengths.