PSR B1919+21
Chart on which Jocelyn Bell Burnell first recognised evidence of PSR B1919+21, exhibited at Cambridge University Library | |
| Observation data Epoch J2000 (ICRS) Equinox J2000 (ICRS) | |
|---|---|
| Constellation | Vulpecula |
| Right ascension | 19h 21m 44.815s |
| Declination | +21° 53′ 02.25″ |
| Characteristics | |
| Evolutionary stage | Pulsar |
| Astrometry | |
| Distance | 1000+2600 −700 ly (300+800 −200 pc) |
| Details | |
| Mass | ~1.4 M☉ |
| Radius | ~1.4 × 10−5 R☉ |
| Luminosity | 0.006 L☉ |
| Rotation | 1.3373 s |
| Age | 16 Myr |
| Other designations | |
| PSR J1921+2153, PSR 1921+2153, PSR B1919+21, PSR 1919+21, WSTB 12W15, CP 1919+21, CP 1919, LGM-1 | |
| Database references | |
| SIMBAD | data |
PSR B1919+21 is a pulsar with a period of 1.3373 seconds and a pulse width of 0.04 seconds. Discovered by Jocelyn Bell Burnell on 28 November 1967, it is the first discovered radio pulsar. The power and regularity of the signals were briefly thought to resemble an extraterrestrial beacon, leading the source to be nicknamed LGM, later LGM-1 (for "little green men").
The original designation of this pulsar was CP 1919, which stands for Cambridge Pulsar at RA 19h 19m . It is also known as PSR J1921+2153 and is located in the constellation of Vulpecula.