Registry · exoplanet

55 Cnc B c

Exoplanet

harvesting The full record is being pulled from the archives right now — measurement tables, the Gaia row, catalogue photometry. This page will fill itself in.

Right ascension: 08h 52m 40.30s
Declination: +28° 18′ 55.0″
Galactic l, b: 196.82, 37.71
Magnitude V: 13.15
Distance: 12.477 pc

Planet

NASA Exoplanet Archive, composite parameters

Host star	55 Cnc B · M4.5 V
Discovery	Radial Velocity, 2025 · Mauna Kea Observatory
Orbital period	33.747 d
Semi-major axis	0.13 au
Eccentricity	0
Radius	2.16 R⊕ · 0.193 R♃
Mass	5.3 M⊕ · 0.01668 M♃
Density	2.89 g/cm³
Equilibrium temperature	230.04 K
System distance	12.477 pc

Recorded parameters

4 quantities with a single published value

Parameter	Value	Unit	Uncertainty	As published	Source	Reference
Mass	5.3	M_earth	± 1.4	Radial Velocity	NASA Exoplanet Archive	Moutou et al. 2026
Orbital period	33.747	d	± 0.035	Radial Velocity	NASA Exoplanet Archive	Moutou et al. 2026
Semi-major axis	0.13	au	± 0.003	Radial Velocity	NASA Exoplanet Archive	Moutou et al. 2026
Eccentricity	0			Radial Velocity	NASA Exoplanet Archive	Moutou et al. 2026

In the same field

within 9 arcmin · wider search

Object	Type	Separation	V
55 Cnc B	Star	0″	—
55 Cnc B b	Exoplanet	0″	13.15
* rho01 Cnc B	HighPM*	8.367″	—
* rho01 Cnc f	Planet	81.47″	—
* rho01 Cnc e	Planet	81.47″	—
* rho01 Cnc	HighPM*	81.47″	—
* rho01 Cnc b	Planet	81.47″	—
* rho01 Cnc c	Planet	81.47″	—
* rho01 Cnc d	Planet	81.47″	—
55 Cnc	Star	84.82″	—
55 Cnc b	Exoplanet	84.82″	5.951

Provenance

where this card came from

Archive	Read at (UTC)	Record
Seeded from the bulk archive load; no per-object fetch yet.

Machine-readable: /api/v1/object/55-cnc-b-c · Registry entry updated 2026-08-14.