PSR B1257+12, previously designated PSR 1257+12, alternatively designated PSR J1300+1240,[6] is a millisecond pulsar located 2,300 light-years from the Sun in the constellation of Virgo, rotating at about 161 times per second (faster than a blender's blade).[1] It is also named Lich, after a powerful, fictional undead creature of the same name.[7][5]

Quick facts: Observation data Epoch J2000.0  &nb...
PSR B1257+12
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Virgo
Right ascension 13h 00m 01s
Declination +12° 40 57
Characteristics
Spectral type Pulsar
Astrometry
Proper motion (μ) RA: 46.44±0.08[1] mas/yr
Dec.: −84.87±0.32[1] mas/yr
Parallax (π)1.41 ± 0.08 mas[1]
Distance2,300 ± 100 ly
(710 ± 40 pc)
Details
Mass1.4[citation needed] M
Radius~0.000015[citation needed] R
Temperature28,856[citation needed] K
Rotation0.006219 s[2]
Age1–3[3][4][lower-alpha 1] Gyr
Other designations
Lich,[5] PSR 1257+12, PSR J1300+1240, PSR 1300+1240
Database references
SIMBADdata
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The pulsar has a planetary system with three known planets, named "Draugr" (PSR B1257+12 b or PSR B1257+12 A), "Poltergeist" (PSR B1257+12 c, or PSR B1257+12 B) and "Phobetor" (PSR B1257+12 d, or PSR B1257+12 C), respectively. They were both the first extrasolar planets and the first pulsar planets to be discovered; B and C in 1992 and A in 1994. A is the lowest-mass planet yet discovered by any observational technique, with somewhat less than twice the mass of Earth's moon.