Temperature
5442 K
5357.5 to 5519
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Stellar HostProfile
K2-189
Unclassified star โข 242.1 pc
Records
10
literature rows
Planets
2
system count
References
10
distinct source labels
TIC: TIC 422349881
Approximate color
from effective temperature
Canonical Summary
Adopted host values from one source row
Values come from the row with the most populated summary measurements. Missing values stay missing. Ranges and counts describe all source rows.
Stellar source: Howard et al. 2025 โข System source: TICv8
Mass
0.85 Msun
0.85 to 0.96
Radius
0.88 Rsun
0.86 to 0.88
Distance
242.1 pc
single adopted value
Planets
2
Stable across source rows
Scale Comparison
Radius against the Sun
Current adopted radius: 0.88 Rโ (circles scaled linearly by radius)
Sun
1.0 Rโ baseline
K2-189
0.88 Rโ
System Layout
Known planets
2 planets linked to this host
K2-189: A Two-Planet System in the Distant Sky
K2-189 is a single-star system located 790 light-years away. Its host star has a reported mass of 0.85 solar masses, a radius of 0.879 solar radii, and a temperature of 5440 K. Compared with the Sun, this star is less massive, physically smaller, and cooler. Two planets have been identified orbiting K2-189, both discovered by the transit method in 2018.
K2-189 b is an Earth-like planet with a radius of 1.4 Earth radii and an orbital period of 2.59 days. Among the listed planets, it has the shortest year and the smallest radius by reported estimates.
K2-189 c is a Super-Earth with a radius of 2.31 Earth radii and an orbital period of 6.68 days. Among the listed planets, it has the longest year and the largest radius by reported estimates.
A transit occurs when a planet passes in front of its star from our viewpoint, causing a small dip in observed brightness. Repeated dips help establish orbital periods. Both K2-189 b and K2-189 c have reported radius estimates larger than Earth's.
Provenance
Underlying measurements and references
Evidence Summary
Rows
10
Stellar refs
9
System refs
1
Distancestable
Parallaxstable
Temperaturedisputed
Massdisputed
Radiusdisputed
Luminositydisputed
Surface Gravitydisputed
Metallicitydisputed
| ST TEFF | ST MASS | ST RAD | ST AGE | ST LUM | ST SPECTYPE | SY DIST | Stellar Ref | System Ref |
|---|---|---|---|---|---|---|---|---|
| โ | โ | 0.88 | โ | โ | โ | 242.1 | Petigura et al. 2018 | TICv8 |
| 5442 | 0.85 | 0.88 | โ | โ | โ | 242.1 | Howard et al. 2025 | TICv8 |
| 5468 | 0.96 | 0.87 | โ | -0.22 | โ | 242.1 | TICv8 | TICv8 |
| 5357.5 | โ | 0.88 | โ | -0.24 | โ | 242.1 | Gaia DR2 | TICv8 |
| โ | โ | โ | โ | โ | โ | 242.1 | Pope et al. 2016 | TICv8 |
| โ | โ | โ | โ | โ | โ | 242.1 | Barros et al. 2016 | TICv8 |
| 5519 | 0.94 | 0.87 | โ | โ | โ | 242.1 | Livingston et al. 2018 | TICv8 |
| โ | โ | 0.88 | โ | โ | โ | 242.1 | Kruse et al. 2019 | TICv8 |
| โ | โ | 0.88 | โ | โ | โ | 242.1 | Kruse et al. 2019 | TICv8 |
| 5503 | 0.93 | 0.86 | โ | โ | โ | 242.1 | Mayo et al. 2018 | TICv8 |