Key parameters at a glance

A radius of 3.89 Earth radii
A mass of 14.43 Earth masses
Surface gravity around 0.95 g
An orbital period of 12.733 days
Semi-major axis 0.1097 AU
Distance from Earth 357.27 light-years
Earth Similarity Index 0.554
Travel time at Voyager 1 speed 6,300,421 years

DMPP-9 b Planet Profile

Physical Specs

Radius

3.89 R⊕

Radius (Jupiter)

0.347 R♃

Mass

14.43 M⊕

Mass (Jupiter)

0.045 M♃

Density

1.35 g/cm³

Surface Gravity

0.95 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.554

HZ Position Unknown

Controversial No

Discovery

Year 2026

Method Radial Velocity

Facility Multiple Observatories

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#28of 1978

top 1.4%

This planet

3.89R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

HD 42618 b 3.89 R⊕ TOI-942 b 3.89 R⊕ HD 20003 c 3.89 R⊕

Metric	Earth	DMPP-9 b	Jupiter
Radius (R⊕)	1.00	3.89	11.21
Mass (M⊕)	1.00	14.43	317.83
Density (g/cm³)	5.51	1.35	1.33
Surface Gravity (g)	1.00	0.95	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	14.430 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 200133

HIP

HIP 104083

TIC

TIC 376777782

Gaia DR2

Gaia DR2 6401028668786744960

Gaia DR3

Gaia DR3 6401028668786744960

System

DMPP-9

Percentile among Sub-Neptune cohort

Radius 3.890 R⊕ · percentile 98 / cohort 1978

Mass 14.430 M⊕ · percentile 91 / cohort 1978

Orbital period 12.73 d · percentile 43 / cohort 1946

Distance 109.54 pc · percentile 22 / cohort 1975

ESI 0.554 · percentile 77 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

12.733 days

Semi-major axis

0.1097 AU

Eccentricity

0.250

Inclination

— °

Year Length

A year here lasts approximately 12.73 Earth days (3.5% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 0.1097 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.554

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Standing et al. 2026

Instrument

Multiple Instruments

Publication

2026-02

Observation locale

Ground

Discovery cohort

Planets confirmed in 2026 at Multiple Observatories (12 shown).

DMPP-6 b · Sub-Neptune TOI-4336 A c · Super-Earth GJ 887 d · Sub-Neptune HD 176986 d · Sub-Neptune GJ 887 e · Rocky Terrestrial DMPP-6 c · Sub-Neptune TOI-5789 d · Super-Earth TOI-5789 e · Sub-Neptune HD 85426 c · Sub-Neptune DMPP-2 c · Neptune-like DMPP-7 b · Neptune-like TOI-375 d · Gas Giant

Host System: DMPP-9

Spectral Class

F-type yellow-white

Effective Temperature

6,092 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.260 R☉

Stellar Mass

1.100 M☉

Metallicity [Fe/H]

—

Extended Stellar Properties

Surface gravity (log g)

4.261 dex

Stellar density

0.717 g/cm³

Systemic radial velocity

11.65 km/s

Rotational v·sin i

3.22 km/s

Rotation period

16.20 days

Distance

109.54 parsec

Light-years 357.27 ly

V-band magnitude

9.22 mag

Voyager-speed travel 6,300,421 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

9.100 mas

Total Proper Motion

86.692 mas/yr

PM Right Ascension

51.49 mas/yr

PM Declination

-69.74 mas/yr

Galactic Cartesian (pc)

x = 0.283 · y = -0.270 · z = -0.920

Equatorial (J2000)

RA 316.30600° · Dec -66.95816°

Galactic ℓ, b

327.312° · -37.705°

Ecliptic λ, β

294.738° · -47.454°

HTM-20 index

-717579351