Key parameters at a glance

A radius of 2.55 Earth radii
A mass of 7.04 Earth masses
Surface gravity around 1.08 g
An orbital period of 28.867 days
Distance from Earth 654.93 light-years
Earth Similarity Index 0.697
Travel time at Voyager 1 speed 11,549,651 years

2 siblings around K2-80

K2-80 d shares its host star with 2 other confirmed planets. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
K2-80 c	Super-Earth	1.47	2.76	5.605	—	2016
K2-80 b	Sub-Neptune	2.01	4.70	19.092	—	2016
K2-80 d this	Sub-Neptune	2.55	7.04	28.867	—	2018

K2-80 d Planet Profile

Physical Specs

Radius

2.55 R⊕

Radius (Jupiter)

0.228 R♃

Mass

7.04 M⊕

Mass (Jupiter)

0.022 M♃

Density

2.33 g/cm³

Surface Gravity

1.08 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.697

HZ Position Unknown

Controversial No

Discovery

Year 2018

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1103of 1978

top 55.7%

This planet

2.55R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-1836 b 2.55 R⊕ Kepler-1681 b 2.55 R⊕ TOI-4602.01 2.55 R⊕

Metric	Earth	K2-80 d	Jupiter
Radius (R⊕)	1.00	2.55	11.21
Mass (M⊕)	1.00	7.04	317.83
Density (g/cm³)	5.51	2.33	1.33
Surface Gravity (g)	1.00	1.08	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 242961495

Gaia DR2

Gaia DR2 38723395078288256

Gaia DR3

Gaia DR3 38723395078288256

System

K2-80

Percentile among Sub-Neptune cohort

Radius 2.552 R⊕ · percentile 44 / cohort 1978

Mass 7.040 M⊕ · percentile 41 / cohort 1978

Orbital period 28.87 d · percentile 72 / cohort 1946

Distance 200.80 pc · percentile 29 / cohort 1975

ESI 0.697 · percentile 92 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

28.867 days

Semi-major axis

— AU

Eccentricity

—

Inclination

89.40 °

Year Length

A year here lasts approximately 28.87 Earth days (7.9% of a terrestrial year).

Transit Fingerprint

Depth

0.086 %

Duration

4.224 h

Rp / R★

0.027806

Transit midpoint (BJD)

2,457,082.9371

Photometric dip

Transit produces a flux drop of 864 ppm lasting ≈ 4.22 h.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.697

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Mayo et al. 2018

Instrument

Kepler CCD Array

Publication

2018-03

Observation locale

Space

Discovery cohort

Planets confirmed in 2018 at K2 (12 shown).

K2-190 c · Rocky Terrestrial K2-183 b · Rocky Terrestrial K2-209 b · Rocky Terrestrial K2-210 b · Rocky Terrestrial K2-165 b · Super-Earth K2-169 b · Super-Earth K2-148 b · Super-Earth K2-219 b · Super-Earth K2-190 b · Super-Earth K2-200 b · Super-Earth K2-201 b · Super-Earth K2-170 b · Super-Earth

Host System: K2-80

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,377 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.841 R☉

Stellar Mass

0.913 M☉

Metallicity [Fe/H]

0.07

Extended Stellar Properties

Surface gravity (log g)

4.650 dex

Stellar density

1.907 g/cm³

Systemic radial velocity

16.78 km/s

Metallicity ratio

[Fe/H]

Distance

200.80 parsec

Light-years 654.93 ly

V-band magnitude

12.69 mag

Voyager-speed travel 11,549,651 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

4.952 mas

Total Proper Motion

60.422 mas/yr

PM Right Ascension

-2.93 mas/yr

PM Declination

-60.35 mas/yr

Galactic Cartesian (pc)

x = 0.500 · y = 0.834 · z = 0.234

Equatorial (J2000)

RA 59.03749° · Dec 13.55903°

Galactic ℓ, b

176.612° · -29.483°

Ecliptic λ, β

59.760° · -6.689°

HTM-20 index

2019361615