Binary star in the constellation Libra
! style="text-align: center; background-color: #FFFFC0;" colspan="2" | Observation dataEpoch J2000
      Equinox J2000
! style="text-align:left" | Constellation
! style="text-align:left" | Right ascension
! style="text-align:left" | Declination
! style="text-align:left" | Apparent magnitude (V)
! style="background-color: #FFFFC0; text-align: center;" colspan="2"| Characteristics
! style="text-align:left" | Spectral type
! style="text-align:left" | B−V 
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HD 133131 is a binary star in the constellation of Libra. It is roughly 168 light-years (51.5 parsecs) away from the Sun. It consists of two G-type main-sequence stars; neither are bright enough to be seen with the naked eye.
Both components, HD 133131 A and B, are very similar to the Sun but are far older, about 6 billion years old. They also have low metallicities (50% of solar abundance), and HD 133131 A is additionally depleted in heavy elements compared to HD 133131 B, indicating a possibly past planetary engulfment event for HD 133131 B.
Planetary system.
In 2016 two planets orbiting HD 133131 A and one planet orbiting HD 133131 B were discovered utilizing the radial velocity method.
! align=center| Companion
! align=center| Mass
! align=center| Semimajor axis
! align=center| Orbital period
! align=center| Eccentricity
! align=center| Inclination
! align=center| Radius
! align=center| Companion
! align=center| Mass
! align=center| Semimajor axis
! align=center| Orbital period
! align=center| Eccentricity
! align=center| Inclination
! align=center| Radius
References.
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