Key parameters at a glance

A radius of 5.70 Earth radii
A mass of 413.18 Earth masses
Surface gravity around 12.72 g
An orbital period of 8.138 days
Equilibrium temperature 850 K (577 °C)
Distance from Earth 143.71 light-years
Earth Similarity Index 0.156
Travel time at Voyager 1 speed 2,534,352 years

DS Tuc A b Planet Profile

Physical Specs

Radius

5.70 R⊕

Radius (Jupiter)

0.509 R♃

Mass

413.18 M⊕

Mass (Jupiter)

1.300 M♃

Density

— g/cm³

Surface Gravity

12.72 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.156

HZ Position Inner

Controversial No

Discovery

Year 2019

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#304of 574

top 52.8%

This planet

5.70R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

HD 127506 b 5.67 R⊕ Kepler-516 b 5.74 R⊕ TOI-1883 b 5.65 R⊕

Metric	Earth	DS Tuc A b	Jupiter
Radius (R⊕)	1.00	5.70	11.21
Mass (M⊕)	1.00	413.18	317.83
Density (g/cm³)	5.51	—	1.33
Surface Gravity (g)	1.00	12.72	2.53
Insolation (S⊕)	1.00	115.83	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	413.179 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

HD 222259 A

HIP

HIP 116748 A

TIC

TIC 410214986

Gaia DR2

Gaia DR2 6387058411482257536

Gaia DR3

Gaia DR3 6387058411482257536

System

DS Tuc

Percentile among Neptune-like cohort

Radius 5.700 R⊕ · percentile 47 / cohort 574

Mass 413.179 M⊕ · percentile 97 / cohort 574

Orbital period 8.14 d · percentile 31 / cohort 524

Distance 44.06 pc · percentile 14 / cohort 572

ESI 0.156 · percentile 16 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

8.138 days

Semi-major axis

— AU

Eccentricity

0.000

Inclination

89.50 °

Year Length

A year here lasts approximately 8.14 Earth days (2.2% of a terrestrial year) on a nearly circular orbit.

Transit Fingerprint

Depth

0.294 %

Duration

3.176 h

Impact parameter b

0.180

Rp / R★

0.054190

Transit midpoint (BJD)

2,458,332.3100

Photometric dip

Transit produces a flux drop of 2,936 ppm lasting ≈ 3.18 h.

Extended Orbital Architecture

Planet / star radius ratio

0.054190

Semi-major axis / stellar radius

20.350

Impact parameter (b)

0.180

Transit mid-time (BJD)

2,458,332.3100

Eq. Temperature

850K

(577 °C)

Insolation (S⊕)

115.83

Earth = 1.00

Earth Similarity (ESI)

0.156

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.

Discovery Paper

Primary reference

Newton et al. 2019

Instrument

TESS CCD Array

Publication

2019-07

Observation locale

Space

Discovery cohort

Planets confirmed in 2019 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

LP 791-18 c · Sub-Neptune LTT 1445 A b · Super-Earth TOI-270 d · Sub-Neptune L 98-59 d · Super-Earth GJ 357 b · Rocky Terrestrial GJ 143 b · Sub-Neptune HD 23472 c · Super-Earth L 98-59 c · Super-Earth LP 791-18 b · Rocky Terrestrial TOI-270 c · Sub-Neptune HD 23472 b · Sub-Neptune TOI-270 b · Super-Earth

Host System: DS Tuc A

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,428 K — cooler than the Sun (5,778 K)

Estimated Age

0.04 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.964 R☉

Stellar Mass

1.010 M☉

Metallicity [Fe/H]

0.00

Extended Stellar Properties

Surface gravity (log g)

4.600 dex

Stellar density

2.400 g/cm³

Systemic radial velocity

8.05 km/s

Rotational v·sin i

17.80 km/s

Rotation period

2.85 days

Activity index (log R'HK)

-4.090

Distance

44.06 parsec

Light-years 143.71 ly

V-band magnitude

8.17 mag

Voyager-speed travel 2,534,352 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

22.666 mas

Total Proper Motion

104.224 mas/yr

PM Right Ascension

79.46 mas/yr

PM Declination

-67.44 mas/yr

Galactic Cartesian (pc)

x = 0.354 · y = -0.031 · z = -0.935

Equatorial (J2000)

RA 354.91547° · Dec -69.19604°

Galactic ℓ, b

312.101° · -46.634°

Ecliptic λ, β

311.436° · -57.687°

HTM-20 index

430226194