WISEP J121756.91+162640.2 A b
WISEP J121756.91+162640.2 A b orbits the star WISEP J121756.91+162640.2 A, 32.9 light-years from Earth.
Get to know this world ↓Size-based classification; composition may be uncertain.
Around 947% wider than Earth.
Its light travels for roughly 33 years to reach us.
Imaging
Overview
WISEP J121756.91+162640.2 A b is one of the confirmed worlds in the NASA Exoplanet Archive. Recorded as discovered in 2012. The credited discovery facility is W. M. Keck Observatory. Its Imaging evidence gives us a way to study a planet that is usually too faint to see directly.
Its recorded radius is 10.47 times Earth's radius. Size is useful for comparison, but it cannot establish surface conditions by itself.
The planet
The archive lists a mass or minimum-mass value of 6,992 Earth masses (Mass). Radius: 10.47 Earth radii.
Mass and radius constrain possible interiors; multiple compositions can fit a given set of measurements.
Orbit & year
The orbital period is not determined in this record. Its recorded semi-major axis is 8 AU. One AU is roughly the Earth–Sun distance.
Host star
Planetary system
1 confirmed planets are stored for this star.
WISEP J121756.91+162640.2 A b · Orbit not determined
Discovery
Reported discovery year: 2012. Method: Imaging. Facility: W. M. Keck Observatory.
First stored in this atlas: 04/10/2026. This is an ingestion date, not a confirmation date.
How these methods work ↗Potential habitability
The data here does not establish habitability, liquid water, or life. An appropriate atmosphere and many other conditions would be needed.
The listed equilibrium temperature is 450 K. This is an estimated energy-balance temperature, not a measured surface temperature.
Understand the habitable zone ↗What do we actually know?
The underlying light, motion or timing signal. Usually not a photograph of the planet.
Parameters derived from observations, with instrument and model uncertainty.
Our light-year conversion and browsing class are calculated from archive values.
Equilibrium temperature is an energy-balance estimate, not surface weather.
Possible composition depends on models and may not be unique.
Surface conditions and the presence of life are not established here.
Measured signals are interpreted through models. The archive’s composite table combines published values and may include calculated estimates. Values do not necessarily form one self-consistent solution.
Radius and mass can be estimated or inferred, orbital period comes from recurring observations, and size classification is calculated by this site. Atmospheric and surface conditions remain unknown unless established by specific observations.
Consult the archive for individual parameter references and uncertainty intervals before scientific use.
Scientific data
| Radius | 10.468 Earth radii |
|---|---|
| Mass / minimum mass | 6,992 Earth masses (Mass) |
| Semi-major axis | 8 AU |
| Equilibrium temperature | 450 K · estimated, not surface temperature |
| Host star temperature | 575 K |
| Host star mass | 0.029 Solar masses |
| Host star radius | 0.091 Solar radii |
| Distance | 10.1 parsecs |
| Discovery year | 2,012 |
| Discovery method | Imaging |
| Discovery facility | W. M. Keck Observatory |
| Discovery publication | 2012-10 |
| Stellar spectral type | T8.5 |
Uncertainties and parameter provenance
Archive uncertainty ranges and published references, where available. A missing uncertainty does not imply an exact value.
| Parameter | Uncertainty / source |
|---|---|
| Radius | +0.327 / -0.327 Leggett et al. 2014 |
| Mass / minimum mass | +636 / -636 Leggett et al. 2014 |
| Equilibrium temperature | Upper uncertainty unavailable / Lower uncertainty unavailable Leggett et al. 2014 |
Sources
NASA Exoplanet Archive · Planetary Systems Composite Parameters (PSCompPars).
Open the scientific archive record ↗Last changed in this atlas: 04/10/2026, 11:39:41. Read our methodology.