Temperature
3192 K
3135 to 3305
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Stellar HostProfile
Ross 128
M4 • 3.37 pc
Records
6
literature rows
Planets
1
system count
References
7
distinct source labels
TIC: TIC 325275315HIP: HIP 57548
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: Bonfils et al. 2018 • System source: TICv8
Mass
0.17 Msun
0.17 to 0.25
Radius
0.20 Rsun
0.20 to 0.22
Age
5 Gyr
single adopted value
Luminosity
-2.44 log(Lsun)
-2.44 to -2.40
Distance
3.37 pc
single adopted value
Spectral Type
M4
Multiple classifications reported
Planets
1
Stable across source rows
Scale Comparison
Radius against the Sun
Current adopted radius: 0.20 R☉ • circles scaled linearly by radius
Sun
1.0 R☉ baseline
Ross 128
0.20 R☉
System Layout
Known planets
1 planets linked to this host
Ross 128 b
Radial Velocity
◌
Discovery
2017
Period
9.87 days
Radius
—
Mass
1.40 M⊕
Eq. Temp
301 K
Ross 128 and Its Planet
Ross 128 is an M4 red dwarf 11 light-years away. Its reported mass is 0.168 solar masses and its reported radius is 0.197 solar radii, both smaller than the Sun's. Its reported temperature of 3190 K is cooler than the Sun's, and its age carries a reported lower limit of 5 billion years.
One planet orbits this star: Ross 128 b, found in 2017 by the radial velocity method, which detects the wobble a planet's gravity induces in its star's motion. Its minimum mass is 1.4 Earth masses, larger than Earth's, and a minimum mass is a lower bound on a planet's true mass rather than an ordinary estimate. The planet completes an orbit every 9.87 days.
Provenance
Underlying measurements and references
Evidence Summary
Rows
6
Stellar refs
6
System refs
1
Distancestable
Parallaxstable
Temperaturedisputed
Massdisputed
Radiusdisputed
Agestable
Luminositydisputed
Surface Gravitystable
Metallicitystable
Spectral Typedisputed
| ST TEFF | ST MASS | ST RAD | ST AGE | ST LUM | ST SPECTYPE | SY DIST | Stellar Ref | System Ref |
|---|---|---|---|---|---|---|---|---|
| 3305 | — | — | — | — | — | 3.37 | Gaia DR2 | TICv8 |
| 3163 | 0.18 | 0.21 | — | -2.40 | — | 3.37 | TICv8 | TICv8 |
| 3135 | 0.25 | 0.22 | — | — | M4.0V | 3.37 | Turnbull 2015 | TICv8 |
| — | — | — | — | — | M4 | 3.37 | Hawley et al. 1996 | TICv8 |
| 3192 | 0.17 | 0.20 | 5 | -2.44 | M4 | 3.37 | Bonfils et al. 2018 | TICv8 |
| — | — | — | — | — | — | 3.37 | Nidever et al. 2002 | TICv8 |