Key parameters at a glance

A radius of 12.80 Earth radii
A mass of 1,719.45 Earth masses
Surface gravity around 10.49 g
An orbital period of 921.200 days
Semi-major axis 1.9610 AU
Distance from Earth 358.31 light-years
Earth Similarity Index 0.434
Travel time at Voyager 1 speed 6,318,884 years

1 sibling around HD 80653

K2-312 c shares its host star with 1 other confirmed planet. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
HD 80653 b	Super-Earth	1.61	5.72	0.720	2,463	2020
K2-312 c this	Gas Giant	12.80	1,719.45	921.200	—	2023

K2-312 c Planet Profile

Physical Specs

Radius

12.80 R⊕

Radius (Jupiter)

1.140 R♃

Mass

1,719.45 M⊕

Mass (Jupiter)

5.410 M♃

Density

4.51 g/cm³

Surface Gravity

10.49 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.434

HZ Position Unknown

Controversial No

Discovery

Year 2023

Method Radial Velocity

Facility Roque de los Muchachos Observatory

Telescope 3.58 m Telescopio Nazionale Galileo

Size rank in cohort

Rank by radius

#1063of 1771

top 60.0%

This planet

12.80R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 240210 b 12.80 R⊕ HD 29985 b 12.80 R⊕ HD 148164 c 12.80 R⊕

Metric	Earth	K2-312 c	Jupiter
Radius (R⊕)	1.00	12.80	11.21
Mass (M⊕)	1.00	1,719.45	317.83
Density (g/cm³)	5.51	4.51	1.33
Surface Gravity (g)	1.00	10.49	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	1,719.452 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 80653

TIC

TIC 55315929

Gaia DR2

Gaia DR2 606477252238780160

Gaia DR3

Gaia DR3 606477252238780160

System

HD 80653

Percentile among Gas Giant cohort

Radius 12.800 R⊕ · percentile 37 / cohort 1771

Mass 1,719.452 M⊕ · percentile 77 / cohort 1747

Orbital period 921.20 d · percentile 76 / cohort 1533

Distance 109.86 pc · percentile 36 / cohort 1759

ESI 0.434 · percentile 95 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

921.200 days

Semi-major axis

1.9610 AU

Eccentricity

0.853

Inclination

— °

Year Length

A year here lasts about 2.52 Earth years on a highly eccentric trajectory at a mean orbital distance of 1.9610 AU.

Extended Orbital Architecture

RV semi-amplitude (K)

194.000 m/s

Transit mid-time (BJD)

2,458,968.8000

Long. of periastron (ω)

41.60°

Angular separation (arcsec)

17.80000

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.434

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Bonomo et al. 2023

Instrument

HARPS-N Spectrograph

Publication

2023-04

Observation locale

Ground

Discovery cohort

Planets confirmed in 2023 at Roque de los Muchachos Observatory (7 shown).

GJ 9404 b · Sub-Neptune Kepler-10 d · Sub-Neptune HD 99492 c · Neptune-like GJ 328 c · Neptune-like Kepler-454 d · Gas Giant TOI-4010 e · Gas Giant Kepler-68 e · Gas Giant

Host System: HD 80653

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,959 K — hotter than the Sun (5,778 K)

Estimated Age

2.67 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.220 R☉

Stellar Mass

1.180 M☉

Metallicity [Fe/H]

0.26

Extended Stellar Properties

Surface gravity (log g)

4.340 dex

Stellar density

0.900 g/cm³

Systemic radial velocity

8.31 km/s

Rotation period

19.55 days

Metallicity ratio

[Fe/H]

Distance

109.86 parsec

Light-years 358.31 ly

V-band magnitude

9.45 mag

Voyager-speed travel 6,318,884 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

9.074 mas

Total Proper Motion

36.276 mas/yr

PM Right Ascension

-33.46 mas/yr

PM Declination

-14.01 mas/yr

Galactic Cartesian (pc)

x = -0.746 · y = 0.618 · z = 0.248

Equatorial (J2000)

RA 140.33908° · Dec 14.36787°

Galactic ℓ, b

216.500° · 39.624°

Ecliptic λ, β

138.231° · -1.047°

HTM-20 index

-347478176