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an open source database of all discovered extrasolar planets

PSR 1257+12

The planetary system PSR 1257+12 hosts at least 3 planets.

  System parameters
Primary system name PSR 1257+12
Alternative system names PSR B1257+12
Right ascension 13 00 03.5767
Declination +12 40 56.4721
Distance [parsec] 710+43−38edit
Distance [lightyears] 2316+140−124
Number of stars in system 1
Number of planets in system 3

ArchitectureArchitecture of the system

This list shows all planetary and stellar components in the system. It gives a quick overview of the hierarchical architecture.

  •  PSR 1257+12, stellar object
    •  PSR 1257+12 A, planet, semi-major axis: 0.1900 AU
      •  PSR 1257+12 B, planet, semi-major axis: 0.360 AU
        •  PSR 1257+12 C, planet, semi-major axis: 0.460 AU

        PlanetsPlanets in the system

        This table lists all planets in the system PSR 1257+12.

          PSR 1257+12 A PSR 1257+12 B PSR 1257+12 C
        Alternative planet names PSR B1257+12 A, PSR 1257+12 b, PSR B1257+12 b PSR B1257+12 B, PSR 1257+12 c, PSR B1257+12 c PSR B1257+12 C, PSR 1257 12 d, PSR B1257+12 d
        Description N/A N/A N/A
        Lists Confirmed planets
        Mass [Mjup] ( 6.3±0.6 )·10-5edit 0.0135±0.0006edit 0.0123±0.0006edit
        Mass [Mearth] 0.020±0.002 4.29±0.19 3.91±0.19
        Radius [Rjup] N/A N/A N/A
        Radius [Rearth] N/A N/A N/A
        Orbital period [days] 25.262±0.003edit 66.5419±0.0001edit 98.2114±0.0002edit
        Semi-major axis [AU] 0.1900edit 0.360edit 0.460edit
        Eccentricity 0.00edit 0.0186±0.0002edit 0.0252±0.0002edit
        Equilibrium temperature [K] N/A N/A N/A
        Discovery method timing
        Discovery year 1992
        Last updated [yy/mm/dd] 16/04/12

        starStars in the system

        This table lists all stars in the system PSR 1257+12.

          PSR 1257+12
        Alternative star names PSR B1257+12, PSR J1300+1240
        Mass [MSun] 1.400edit
        Radius [RSun] 1.400 ·10-5edit
        Age [Gyr] 3.00edit
        Metallicity [Fe/H] N/A
        Temperature [K] N/A
        Spectral type Pulsar
        Visual magnitude N/A

        Planet sizes

        The following plot shows the approximate sizes of the planets in this system The Solar System planets are shown as a comparison. Note that unless the radius has been determined through a transit observation, this is only an approximation (see Lissauer et al. 2011b).

        PlutoMercuryMarsVenusEarthNeptuneUranusSaturnJupiterPSR 1257+12 APSR 1257+12 BPSR 1257+12 C

        referencesScientific references and contributors

        Links to scientific papers and other data sources


        This table lists all links which are relevant to this particular system. Note that this is just a summary. More references to the scientific publications and comments can be found in the commit messages. To see these, head over the github or click here to directly go to the git blame output of this system. In the left column of the output you can see the commit message corresponding to each parameter. It also lists the date of the last commit and the person making the changes. Within the commit message, you will find a link to the scientific publication where the data is taken from. Note that this is a new feature and not all system parameters might have a reference associated with it yet. Please help making this catalogue better and contribute data or references!

        Open Exoplanet Catalogue contributors

        Contributor E-mail Number of commits
        Andrew Tribick ajtribick(at) 2

        This table lists all people who have contributed to the Open Exoplanet Catalogue. Please consider contributing! Click here to find out how. You can also view all commits contributing to this file on github.

        xmlData download

        You can download the xml file corresponding to this planetary system, which is part of the Open Exoplanet Catalogue. All information on this page has been directly generated from this XML file. You can also download the entire catalogue over at github. If you prefer to download the dataset as an ASCII tables, you might find the oec_tables repository usefule.


        If you spot an error or if you can contribute additional data to this entry, please send an e-mail to Please include the corrected xml file and a reference to where the new data is coming from, ideally a scientific paper. If you are fluent with git and github, you can also create a pull request or open an issue on the Open Exoplanet Catalogue repository. Please include the reference to the relevant scientific paper in your commit message.