Key parameters at a glance

A radius of 2.43 Earth radii
A mass of 6.50 Earth masses
Surface gravity around 1.10 g
An orbital period of 5.657 days
Semi-major axis 0.0600 AU
Equilibrium temperature 1,211 K (938 °C)
Distance from Earth 1,554.80 light-years
Earth Similarity Index 0.205
Travel time at Voyager 1 speed 27,418,816 years

K2-44 b Planet Profile

Physical Specs

Radius

2.43 R⊕

Radius (Jupiter)

0.217 R♃

Mass

6.50 M⊕

Mass (Jupiter)

0.020 M♃

Density

2.48 g/cm³

Surface Gravity

1.10 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.205

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1279of 1978

top 64.6%

This planet

2.43R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-1054.01 2.43 R⊕ Kepler-1739 b 2.43 R⊕ Kepler-55 b 2.43 R⊕

Metric	Earth	K2-44 b	Jupiter
Radius (R⊕)	1.00	2.43	11.21
Mass (M⊕)	1.00	6.50	317.83
Density (g/cm³)	5.51	2.48	1.33
Surface Gravity (g)	1.00	1.10	2.53
Insolation (S⊕)	1.00	646.00	0.037

Star Catalogue Identifiers

TIC

TIC 49427836

Gaia DR2

Gaia DR2 3793339378098543616

Gaia DR3

Gaia DR3 3793339378098543616

System

K2-44

Percentile among Sub-Neptune cohort

Radius 2.433 R⊕ · percentile 35 / cohort 1978

Mass 6.500 M⊕ · percentile 33 / cohort 1978

Orbital period 5.66 d · percentile 15 / cohort 1946

Distance 476.70 pc · percentile 46 / cohort 1975

ESI 0.205 · percentile 7 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

5.657 days

Semi-major axis

0.0600 AU

Eccentricity

—

Inclination

87.99 °

Year Length

A year here lasts approximately 5.66 Earth days (1.5% of a terrestrial year) at a mean orbital distance of 0.0600 AU.

Transit Fingerprint

Depth

0.033 %

Duration

4.296 h

Impact parameter b

0.290

Rp / R★

0.014100

Transit midpoint (BJD)

2,456,811.7094

Photometric dip

Transit produces a flux drop of 334 ppm lasting ≈ 4.30 h.

Extended Orbital Architecture

Planet / star radius ratio

0.014100

Semi-major axis / stellar radius

9.378

Impact parameter (b)

0.290

Transit mid-time (BJD)

2,456,811.7094

Angular separation (arcsec)

0.12600

Eq. Temperature

1,211K

(938 °C)

Insolation (S⊕)

646.00

Earth = 1.00

Earth Similarity (ESI)

0.205

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.

Discovery Paper

Primary reference

Crossfield et al. 2016

Instrument

Kepler CCD Array

Publication

2016-09

Observation locale

Space

Discovery cohort

Planets confirmed in 2016 at K2 (12 shown).

K2-72 d · Rocky Terrestrial K2-72 b · Rocky Terrestrial K2-91 b · Rocky Terrestrial K2-72 c · Rocky Terrestrial K2-102 b · Super-Earth K2-90 c · Super-Earth K2-72 e · Super-Earth K2-83 b · Rocky Terrestrial K2-88 b · Rocky Terrestrial K2-80 c · Super-Earth K2-83 c · Super-Earth K2-65 b · Super-Earth

Host System: K2-44

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,912 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.580 R☉

Stellar Mass

1.150 M☉

Metallicity [Fe/H]

0.00

Extended Stellar Properties

Surface gravity (log g)

4.101 dex

Stellar density

0.322 g/cm³

Systemic radial velocity

47.46 km/s

Metallicity ratio

[Fe/H]

Distance

476.70 parsec

Light-years 1,554.80 ly

V-band magnitude

12.27 mag

Voyager-speed travel 27,418,816 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

2.070 mas

Total Proper Motion

14.078 mas/yr

PM Right Ascension

6.48 mas/yr

PM Declination

-12.50 mas/yr

Galactic Cartesian (pc)

x = -0.994 · y = 0.104 · z = -0.044

Equatorial (J2000)

RA 174.01166° · Dec -2.52093°

Galactic ℓ, b

268.470° · 55.225°

Ecliptic λ, β

175.500° · -4.693°

HTM-20 index

-1068572780