Artist impression of PSR B1257+12 c exoplanet
Confirmed Exoplanet Discovered 1992

PSR B1257+12 c

A super-earth orbiting the unknown PSR B1257+12, located approximately 1,956.9 light-years from Earth.

Image: Wikimedia Commons · CC BY-SA 3.0 · Tyrogthekreeper (talk)

Key parameters at a glance

  • A radius of 1.91 Earth radii
  • A mass of 4.30 Earth masses
  • Surface gravity around 1.18 g
  • An orbital period of 66.542 days
  • Semi-major axis 0.3600 AU
  • Distance from Earth 1,956.94 light-years
  • Earth Similarity Index 0.802
  • Travel time at Voyager 1 speed 34,510,564 years

Context from the literature

PSR B1257+12 c, alternatively designated PSR B1257+12 B, also named Poltergeist, is an extrasolar planet approximately 2,300 light-years away in the constellation of Virgo. It was one of the first planets ever discovered outside the Solar System, and is one of three pulsar planets known to be orbiting the pulsar Lich.

Excerpted from Wikipedia · full article

2 siblings around PSR B1257+12

PSR B1257+12 c shares its host star with 2 other confirmed planets. Side-by-side measurements below.

Planet Type Radius (R⊕) Mass (M⊕) Period (d) Eq. T (K) Year
PSR B1257+12 b Rocky Terrestrial 0.34 0.02 25.262 — 1994
PSR B1257+12 c this Super-Earth 1.91 4.30 66.542 — 1992
PSR B1257+12 d Super-Earth 1.80 3.90 98.211 — 1992

PSR B1257+12 c Planet Profile

Physical Specs

Radius
1.91 R⊕
Radius (Jupiter)
0.170 R♃
Mass
4.30 M⊕
Mass (Jupiter)
0.014 M♃
Density
3.39 g/cm³
Surface Gravity
1.18 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.802
HZ Position Unknown
Controversial No

Discovery

Year 1992
Method Pulsar Timing
Facility Arecibo Observatory
Telescope 305 m Arecibo Radio Telescope

Size rank in cohort

Rank by radius

#114of 1176

top 9.6%

This planet

1.91R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-1121 b 1.91 R⊕ Kepler-524 b 1.91 R⊕ Kepler-1306 b 1.91 R⊕
Metric Earth PSR B1257+12 c Jupiter
Radius (R⊕)1.001.9111.21
Mass (M⊕)1.004.30317.83
Density (g/cm³)5.513.391.33
Surface Gravity (g)1.001.182.53
Insolation (S⊕)1.00—0.037

Alternative Mass Estimates

Method Value Interpretation
Best measured mass 4.300 M⊕ Direct mass measurement (not derived).
Minimum mass (M sin i) 3.400 M⊕ Lower bound from radial-velocity fitting.

Percentile among Super-Earth cohort

Radius 1.910 R⊕ · percentile 90 / cohort 1176
Mass 4.300 M⊕ · percentile 82 / cohort 1176
Orbital period 66.54 d · percentile 97 / cohort 1164
Distance 600.00 pc · percentile 54 / cohort 1171
ESI 0.802 · percentile 89 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period
66.542 days
Semi-major axis
0.3600 AU
Eccentricity
0.019
Inclination
53.00 °

Year Length

A year here lasts approximately 66.54 Earth days (18.2% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.3600 AU.

Eq. Temperature

—

 

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.802

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Wolszczan et al. 1992

Instrument

Arecibo Radio Reciever

Publication

1992-01

Observation locale

Ground

Host System: PSR B1257+12

Spectral Class

Unknown

Effective Temperature

—

Estimated Age

3.00 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

—

Stellar Mass

1.400 M☉

Metallicity [Fe/H]

—

Distance
600.00 parsec
Light-years 1,956.94 ly
V-band magnitude
— mag
Voyager-speed travel 34,510,564 yr
Wikipedia → Image: Wikimedia Commons · Tyrogthekreeper (talk) · CC BY-SA 3.0

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Artist impression of PSR B1257+12 d exoplanet

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