55 Cnc B b
Orbiting 55 Cnc B
55 Cnc B b is an exoplanet orbiting the star 55 Cnc B, discovered in 2025 using the Radial Velocity method.
Minimum Mass (M sin i)
3.50
Earth masses
Orbital Period
6.8
days
Distance
12.5
parsecs
Radius (Earth radii)
Unknown
Minimum Mass, M sin(i) (Earth masses)
3.50
Radial-velocity minimum
Equilibrium Temperature
Unknown
Parameter source: Moutou et al. 2026
Orbital Period
6.799+0.001−0.001days
Semi-Major Axis
0.0440+0.0012−0.0012au
M sin(i) (Earth masses)
3.50+0.80−0.80
M sin(i) (Jupiter masses)
0.0110+0.0025−0.0025
Eccentricity
0.0000
Radial Velocity Semi-Amplitude
2.89+0.61−0.63m/s
Distance from Earth
12.5 pc (~41 ly)
Spectral Type
M4.5 V
Temperature
3286 K
Mass (Solar)
0.26 M☉
Radius (Solar)
0.27 R☉
Luminosity
Unknown
Planets in System
7
Stars in System
2
Coordinates (RA, Dec)
133.1679°, 28.3153°
Discovery Method
Radial Velocity
Discovery Year
2025
Source ID: 55 Cnc B b
55 Cnc B b orbits 55 Cnc B and was reported in 2025 and was detected with the Radial Velocity method.
Published measurements list a minimum mass of 3.5 Earth masses (M sin i) and an orbital period of 6.8 days.
Catalog data places the system at about 12.5 parsecs from Earth, a host star classified as M4.5 V, and 7 known planets in the system.
Host star
Explore the stellar record for this system to compare temperature, spectral type, and known planets.
Open 55 Cnc BMore planets in this system