Key parameters at a glance

A radius of 1.21 Earth radii
A mass of 1.92 Earth masses
Surface gravity around 1.31 g
An orbital period of 0.664 days
Semi-major axis 0.0143 AU
Equilibrium temperature 1,703 K (1430 °C)
Distance from Earth 2,877.75 light-years
Earth Similarity Index 0.169
Travel time at Voyager 1 speed 50,749,165 years
Almost certainly tidally locked to its host star given the close orbit

Kepler-1284 b Planet Profile

Physical Specs

Radius

1.21 R⊕

Radius (Jupiter)

0.108 R♃

Mass

1.92 M⊕

Mass (Jupiter)

0.006 M♃

Density

5.96 g/cm³

Surface Gravity

1.31 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.169

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#56of 570

top 9.6%

This planet

1.21R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

Kepler-415 b 1.21 R⊕ Kepler-169 c 1.21 R⊕ Kepler-189 b 1.21 R⊕

Metric	Earth	Kepler-1284 b	Jupiter
Radius (R⊕)	1.00	1.21	11.21
Mass (M⊕)	1.00	1.92	317.83
Density (g/cm³)	5.51	5.96	1.33
Surface Gravity (g)	1.00	1.31	2.53
Insolation (S⊕)	1.00	2,190.08	0.037

Star Catalogue Identifiers

TIC

TIC 159726546

Gaia DR2

Gaia DR2 2129192692257862912

Gaia DR3

Gaia DR3 2129192692257862912

System

Kepler-1284

Percentile among Rocky Terrestrial cohort

Radius 1.210 R⊕ · percentile 87 / cohort 570

Mass 1.920 M⊕ · percentile 80 / cohort 570

Orbital period 0.66 d · percentile 5 / cohort 567

Distance 882.32 pc · percentile 90 / cohort 566

ESI 0.169 · percentile 8 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

0.664 days

Semi-major axis

0.0143 AU

Eccentricity

0.000

Inclination

82.63 °

Year Length

A year here lasts roughly 15.9 hours long on a nearly circular orbit at a mean orbital distance of 0.0143 AU.

Transit Fingerprint

Depth

0.021 %

Duration

1.102 h

Impact parameter b

0.019

Rp / R★

0.013539

Transit midpoint (BJD)

2,454,966.4033

Photometric dip

Transit produces a flux drop of 213 ppm lasting ≈ 1.10 h.

Extended Orbital Architecture

Planet / star radius ratio

0.013539

Semi-major axis / stellar radius

4.702

Impact parameter (b)

0.019

Transit mid-time (BJD)

2,454,966.4033

Angular separation (arcsec)

0.01620

Eq. Temperature

1,703K

(1430 °C)

Insolation (S⊕)

2,190.08

Earth = 1.00

Earth Similarity (ESI)

0.169

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Morton et al. 2016

Instrument

Kepler CCD Array

Publication

2016-05

Observation locale

Space

Discovery cohort

Planets confirmed in 2016 at Kepler (12 shown).

Kepler-1512 b · Rocky Terrestrial Kepler-1410 b · Super-Earth Kepler-560 b · Super-Earth Kepler-1389 b · Super-Earth Kepler-1450 b · Super-Earth Kepler-1544 b · Super-Earth Kepler-1459 b · Super-Earth Kepler-1638 b · Super-Earth Kepler-737 b · Super-Earth Kepler-1185 b · Super-Earth Kepler-1178 b · Rocky Terrestrial Kepler-1040 b · Sub-Neptune

Host System: Kepler-1284

Spectral Class

K-type orange

Effective Temperature

5,123 K — cooler than the Sun (5,778 K)

Estimated Age

4.47 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.790 R☉

Stellar Mass

0.840 M☉

Metallicity [Fe/H]

0.03

Extended Stellar Properties

Surface gravity (log g)

4.570 dex

Stellar density

2.940 g/cm³

Metallicity ratio

[Fe/H]

Distance

882.32 parsec

Light-years 2,877.75 ly

V-band magnitude

15.91 mag

Voyager-speed travel 50,749,165 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.105 mas

Total Proper Motion

20.930 mas/yr

PM Right Ascension

-4.98 mas/yr

PM Declination

-20.33 mas/yr

Galactic Cartesian (pc)

x = 0.244 · y = -0.627 · z = 0.739

Equatorial (J2000)

RA 291.27895° · Dec 47.68758°

Galactic ℓ, b

79.487° · 14.446°

Ecliptic λ, β

310.963° · 68.122°

HTM-20 index

-244624364