---
title: "The PSR B1257+12 system"
url: "https://spacecatalog.org/system/psr-b1257-12"
release: "DR1"
licence: "No licence stated; acknowledgement requested"
citation: "This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Cite Christiansen et al. (2025), Planetary Science Journal (doi:10.3847/PSJ/ade3c2), and the literature reference given with each value."
---

# The PSR B1257+12 system

PSR B1257+12 is a star in Virgo, 1957 ly away, with 3 known planets. Their orbits run from 0.190 to 0.460 AU. All of them were detected by pulsar timing.

## The planets, innermost first

| Planet | Orbit (AU) | Period | Radius | Mass | Equilibrium T |
| --- | --- | --- | --- | --- | --- |
| [b](https://spacecatalog.org/object/psr-b1257-12-b) | 0.190 | 25.26 d | 0.34 R⊕ | 0.02 M⊕ | — |
| [c](https://spacecatalog.org/object/psr-b1257-12-c) | 0.360 | 66.54 d | 1.91 R⊕ | 4.3 M⊕ | — |
| [d](https://spacecatalog.org/object/psr-b1257-12-d) | 0.460 | 98.21 d | 1.80 R⊕ | 3.9 M⊕ | — |

Every figure is the planet's composite parameter from the [NASA Exoplanet Archive (Planetary Systems Composite Parameters)](https://exoplanetarchive.ipac.caltech.edu/cgi-bin/TblView/nph-tblView?app=ExoTbls&config=PSCompPars), one consistent set per world. Semi-major axes are orbits about the star, not distances from Earth.

This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Cite Christiansen et al. (2025), Planetary Science Journal (doi:10.3847/PSJ/ade3c2), and the literature reference given with each value.

## The host star

| Quantity | Value |
| --- | --- |
| MASS | 1.4 M☉ |
| DISTANCE FROM EARTH | 1957 ly |
| CONSTELLATION | Virgo |
| STARS IN SYSTEM | 1 |

The star itself: https://spacecatalog.org/object/psr-b1257-12

The page itself, with the orbits drawn: https://spacecatalog.org/system/psr-b1257-12