PSR J1748−2021B

PSR J1748−2021B is the most massive known pulsar, initially calculated with 2.74+0.21
−0.21 M_☉. It was first discovered by Freire^[1] using the Green Bank Telescope S band receiver and Pulsar Spigot Spectrometer in Terzan 5 of globular cluster M-5.^[2]

PSR J174−2021B

Event type	Neutron star, binary pulsar
Pulsar
Date	March 2008
Duration	7514 and 4285 sec
Instrument	Green Bank Telescope
Constellation	Virgo
Right ascension	17h 48m 52.9522s (287.2205342°)
Declination	−20° 21′ 38.90″ (−20.360881°)
Epoch	2000
Galactic coordinates	NGC 6440
Distance	223 pc
Source	SIMBAD
Remnant	17
Host	https://simbad.u-strasbg.fr/simbad/sim-ref?bibcode=2008ApJ...675..670F
Colour (B-V)	BRIGHT 2
Peak apparent magnitude	2.548 Solar mass
Other designations	NGC 6440B
Website	https://simbad.cds.unistra.fr/mobile/object.html?object_name=PSR%20J1748-2021B
Related media on Commons

A later estimate puts the mass as 2.548+0.047
−0.078 M_☉.^[3]