Key parameters at a glance

A radius of 1.49 Earth radii
A mass of 2.82 Earth masses
Surface gravity around 1.27 g
An orbital period of 12.828 days
Semi-major axis 0.0712 AU
Equilibrium temperature 347 K (74 °C)
Distance from Earth 34.64 light-years
Earth Similarity Index 0.814
Travel time at Voyager 1 speed 610,802 years
Almost certainly tidally locked to its host star given the close orbit

4 siblings around L 98-59

L 98-59 e shares its host star with 4 other confirmed planets. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
L 98-59 b	Rocky Terrestrial	0.84	0.46	2.253	620	2019
L 98-59 c	Super-Earth	1.33	2.00	3.691	526	2019
L 98-59 d	Super-Earth	1.63	1.64	7.451	416	2019
L 98-59 e this	Super-Earth	1.49	2.82	12.828	347	2021
L 98-59 f	Super-Earth	1.48	2.80	23.064	285	2025

L 98-59 e Planet Profile

Physical Specs

Radius

1.49 R⊕

Radius (Jupiter)

0.133 R♃

Mass

2.82 M⊕

Mass (Jupiter)

0.009 M♃

Density

5.20 g/cm³

Surface Gravity

1.27 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.814

HZ Position Inner

Controversial No

Discovery

Year 2021

Method Radial Velocity

Facility Multiple Observatories

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#766of 1176

top 65.1%

This planet

1.49R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-174 c 1.49 R⊕ TOI-431 c 1.49 R⊕ Kepler-400 c 1.49 R⊕

Metric	Earth	L 98-59 e	Jupiter
Radius (R⊕)	1.00	1.49	11.21
Mass (M⊕)	1.00	2.82	317.83
Density (g/cm³)	5.51	5.20	1.33
Surface Gravity (g)	1.00	1.27	2.53
Insolation (S⊕)	1.00	2.40	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	2.820 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

TIC

TIC 307210830

Gaia DR2

Gaia DR2 5271055243163629056

Gaia DR3

Gaia DR3 5271055243163629056

System

L 98-59

Percentile among Super-Earth cohort

Radius 1.490 R⊕ · percentile 34 / cohort 1176

Mass 2.820 M⊕ · percentile 32 / cohort 1176

Orbital period 12.83 d · percentile 72 / cohort 1164

Distance 10.62 pc · percentile 2 / cohort 1171

ESI 0.814 · percentile 90 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

12.828 days

Semi-major axis

0.0712 AU

Eccentricity

0.012

Inclination

80.00 °

Year Length

A year here lasts approximately 12.83 Earth days (3.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0712 AU.

Extended Orbital Architecture

Semi-major axis / stellar radius

49.800

RV semi-amplitude (K)

1.820 m/s

Transit mid-time (BJD)

2,458,438.4800

Long. of periastron (ω)

165.00°

Angular separation (arcsec)

6.70000

Eq. Temperature

347K

(74 °C)

Insolation (S⊕)

2.40

Earth = 1.00

Earth Similarity (ESI)

0.814

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — liquid water is physically possible with adequate atmospheric pressure. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Demangeon et al. 2021

Instrument

Multiple Instruments

Publication

2021-09

Observation locale

Multiple Locales

Discovery cohort

Planets confirmed in 2021 at Multiple Observatories (12 shown).

GJ 393 b · Rocky Terrestrial HD 168009 b · Sub-Neptune HD 164922 e · Sub-Neptune HD 95735 c · Sub-Neptune HD 141004 b · Sub-Neptune HD 107148 c · Neptune-like TOI-178 f · Sub-Neptune TYC 0434-04538-1 b · Gas Giant HIP 56640 b · Gas Giant HD 137496 c · Gas Giant HD 156668 c · Neptune-like HD 145675 c · Gas Giant

Host System: L 98-59

Spectral Class

M-type red dwarf

Effective Temperature

3,415 K — cooler than the Sun (5,778 K)

Estimated Age

4.94 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.316 R☉

Stellar Mass

0.292 M☉

Metallicity [Fe/H]

-0.46

Extended Stellar Properties

Surface gravity (log g)

4.910 dex

Stellar density

13.000 g/cm³

Systemic radial velocity

-5.68 km/s

Rotational v·sin i

0.00 km/s

Rotation period

77.50 days

Metallicity ratio

[Fe/H]

Distance

10.62 parsec

Light-years 34.64 ly

V-band magnitude

11.69 mag

Voyager-speed travel 610,802 yr

Multi-band Host Photometry — 13 bands

Astrometric Data

Parallax

94.139 mas

Total Proper Motion

353.413 mas/yr

PM Right Ascension

94.77 mas/yr

PM Declination

-340.47 mas/yr

Galactic Cartesian (pc)

x = -0.209 · y = 0.304 · z = -0.929

Equatorial (J2000)

RA 124.53286° · Dec -68.31447°

Galactic ℓ, b

281.817° · -17.593°

Ecliptic λ, β

203.326° · -76.814°

HTM-20 index

1081502068