Key parameters at a glance

A radius of 1.82 Earth radii
A mass of 3.95 Earth masses
Surface gravity around 1.19 g
An orbital period of 2.291 days
Semi-major axis 0.0185 AU
Equilibrium temperature 464 K (191 °C)
Distance from Earth 28.07 light-years
Earth Similarity Index 0.594
Travel time at Voyager 1 speed 495,063 years
Almost certainly tidally locked to its host star given the close orbit

CD Cet b Planet Profile

Physical Specs

Radius

1.82 R⊕

Radius (Jupiter)

0.162 R♃

Mass

3.95 M⊕

Mass (Jupiter)

0.012 M♃

Density

3.60 g/cm³

Surface Gravity

1.19 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.594

HZ Position Inner

Controversial No

Discovery

Year 2020

Method Radial Velocity

Facility Calar Alto Observatory

Telescope 3.5 m telescope

Size rank in cohort

Rank by radius

#235of 1176

top 19.9%

This planet

1.82R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-283 c 1.82 R⊕ Kepler-1262 b 1.82 R⊕ Kepler-113 b 1.82 R⊕

Metric	Earth	CD Cet b	Jupiter
Radius (R⊕)	1.00	1.82	11.21
Mass (M⊕)	1.00	3.95	317.83
Density (g/cm³)	5.51	3.60	1.33
Surface Gravity (g)	1.00	1.19	2.53
Insolation (S⊕)	1.00	8.60	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	3.950 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

TIC

TIC 328465904

Gaia DR2

Gaia DR2 3179036008830848

Gaia DR3

Gaia DR3 3179036008830848

System

CD Cet

Percentile among Super-Earth cohort

Radius 1.820 R⊕ · percentile 79 / cohort 1176

Mass 3.950 M⊕ · percentile 72 / cohort 1176

Orbital period 2.29 d · percentile 14 / cohort 1164

Distance 8.61 pc · percentile 2 / cohort 1171

ESI 0.594 · percentile 80 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

2.291 days

Semi-major axis

0.0185 AU

Eccentricity

—

Inclination

87.48 °

Year Length

A year here lasts approximately 2.29 Earth days (0.6% of a terrestrial year) at a mean orbital distance of 0.0185 AU.

Eq. Temperature

464K

(191 °C)

Insolation (S⊕)

8.60

Earth = 1.00

Earth Similarity (ESI)

0.594

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Bauer et al. 2020

Instrument

CARMENES

Publication

2020-08

Observation locale

Ground

Host System: CD Cet

Spectral Class

M-type red dwarf

Effective Temperature

3,130 K — cooler than the Sun (5,778 K)

Estimated Age

3.00 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.175 R☉

Stellar Mass

0.161 M☉

Metallicity [Fe/H]

0.13

Extended Stellar Properties

Surface gravity (log g)

4.930 dex

Stellar density

30.359 g/cm³

Rotational v·sin i

2.00 km/s

Rotation period

126.20 days

Activity index (log R'HK)

-5.160

Metallicity ratio

[Fe/H]

Distance

8.61 parsec

Light-years 28.07 ly

V-band magnitude

13.95 mag

Voyager-speed travel 495,063 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

116.154 mas

Total Proper Motion

1,743.983 mas/yr

PM Right Ascension

1,741.86 mas/yr

PM Declination

86.02 mas/yr

Galactic Cartesian (pc)

x = 0.662 · y = 0.745 · z = 0.083

Equatorial (J2000)

RA 48.35302° · Dec 4.77519°

Galactic ℓ, b

175.427° · -43.168°

Ecliptic λ, β

47.243° · -12.699°

HTM-20 index

1209251867