Confirmed Exoplanet Discovered 2019

HIP 54373 c

A sub-neptune orbiting the k-type orange HIP 54373, located approximately 61.0 light-years from Earth.

Key parameters at a glance

  • A radius of 3.57 Earth radii
  • A mass of 12.44 Earth masses
  • Surface gravity around 0.98 g
  • An orbital period of 15.144 days
  • Semi-major axis 0.0990 AU
  • Distance from Earth 61.05 light-years
  • Earth Similarity Index 0.581
  • Travel time at Voyager 1 speed 1,076,546 years
  • Almost certainly tidally locked to its host star given the close orbit

1 sibling around HIP 54373

HIP 54373 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
HIP 54373 b Sub-Neptune 2.87 8.62 7.760 — 2019
HIP 54373 c this Sub-Neptune 3.57 12.44 15.144 — 2019

HIP 54373 c Planet Profile

Physical Specs

Radius
3.57 R⊕
Radius (Jupiter)
0.318 R♃
Mass
12.44 M⊕
Mass (Jupiter)
0.039 M♃
Density
1.50 g/cm³
Surface Gravity
0.98 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.581
HZ Position Unknown
Controversial No

Discovery

Year 2019
Method Radial Velocity
Facility Las Campanas Observatory
Telescope 6.5 m Magellan II Clay Telescope

Size rank in cohort

Rank by radius

#150of 1978

top 7.5%

This planet

3.57R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

K2-217 b 3.58 R⊕ TOI-7384 b 3.56 R⊕ Kepler-734 b 3.56 R⊕
Metric Earth HIP 54373 c Jupiter
Radius (R⊕)1.003.5711.21
Mass (M⊕)1.0012.44317.83
Density (g/cm³)5.511.501.33
Surface Gravity (g)1.000.982.53
Insolation (S⊕)1.00—0.037

Alternative Mass Estimates

Method Value Interpretation
Minimum mass (M sin i) 12.440 M⊕ Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HIP

HIP 54373

TIC

TIC 410407964

Gaia DR2

Gaia DR2 3552000252294347392

Gaia DR3

Gaia DR3 3552000252294347392

System

HIP 54373

Percentile among Sub-Neptune cohort

Radius 3.570 R⊕ · percentile 92 / cohort 1978
Mass 12.440 M⊕ · percentile 85 / cohort 1978
Orbital period 15.14 d · percentile 51 / cohort 1946
Distance 18.72 pc · percentile 4 / cohort 1975
ESI 0.581 · percentile 80 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period
15.144 days
Semi-major axis
0.0990 AU
Eccentricity
0.200
Inclination
— °

Year Length

A year here lasts approximately 15.14 Earth days (4.1% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 0.0990 AU.

Eq. Temperature

—

 

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.581

0 = alien, 1 = Earth-identical

Insufficient insolation data. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Feng et al. 2019

Instrument

Carnegie Planet Finder Spectrograph

Publication

2019-06

Observation locale

Ground

Discovery cohort

Planets confirmed in 2019 at Las Campanas Observatory (12 shown).

HD 39855 b · Sub-Neptune HIP 54373 b · Sub-Neptune HD 103949 b · Sub-Neptune HD 24085 b · Sub-Neptune HIP 35173 b · Sub-Neptune HD 211970 b · Sub-Neptune HD 64114 b · Neptune-like HIP 71135 b · Neptune-like HD 206255 b · Neptune-like HD 21411 b · Neptune-like HD 8326 b · Neptune-like HD 102843 b · Gas Giant

Host System: HIP 54373

Spectral Class

K-type orange

Effective Temperature

4,021 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.565 R☉

Stellar Mass

0.570 M☉

Metallicity [Fe/H]

—

Extended Stellar Properties

Surface gravity (log g)

4.681 dex

Stellar density

4.366 g/cm³

Systemic radial velocity

-4.37 km/s

Distance
18.72 parsec
Light-years 61.05 ly
V-band magnitude
10.38 mag
Voyager-speed travel 1,076,546 yr

Multi-band Host Photometry — 11 bands

6.311.811.81B10.38V9.64Gaia8.67TESS7.45J6.85H6.62K6.52W16.40W26.43W36.26W4

Astrometric Data

Parallax

53.399 mas

Total Proper Motion

239.476 mas/yr

PM Right Ascension

-235.02 mas/yr

PM Declination

-45.99 mas/yr

Galactic Cartesian (pc)

x = -0.919 · y = 0.214 · z = -0.330

Equatorial (J2000)

RA 166.86435° · Dec -19.29169°

Galactic ℓ, b

271.650° · 37.185°

Ecliptic λ, β

175.927° · -22.857°

HTM-20 index

1706631384

Similar Worlds

K2-8 b

Sub-Neptune · K-type orange

Radius 3.58 R⊕ · 1,316.1 ly

KOBE-1 c

Sub-Neptune · K-type orange

Radius 3.56 R⊕ · 78.2 ly

TOI-2076 c

Sub-Neptune · K-type orange

Radius 3.54 R⊕ · 136.7 ly

Kepler-1143 c

Sub-Neptune · K-type orange

Radius 3.60 R⊕ · 1,810.8 ly

Kepler-305 b

Sub-Neptune · K-type orange

Radius 3.60 R⊕ · 2,832.6 ly

K2-285 c

Sub-Neptune · K-type orange

Radius 3.53 R⊕ · 505.4 ly

Explore Related Categories

Sub-Neptune Planets Radial Velocity Discoveries Las Campanas Observatory Mission K-type orange Hosts