Surface temperature 6,116 K | Magnitude 12.4 Apparent magnitude (V) 12.4 | |
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Mass 2.486 × 10^30 kg (1.25 M☉) Radius 1.153 million km (1.656 R☉) Similar Kepler‑56, Kepler‑33, Kepler‑80, Kepler‑32, Kepler‑102 | ||
Kepler-89 is a star with four confirmed planets. Kepler-89 is a possible wide binary star.
Planetary system
The discovery of four planets orbiting the star was announced October 2012 by analyzing data gathered by Kepler space telescope. Follow-up radial velocity measurements confirmed the existence of Kepler-89d, indicating that Kepler-89d is slightly larger and more massive than Saturn. In October 2013, other three planets were confirmed with Kepler-89c and Kepler-89e getting reasonable mass constraints. Transit-timing variations of the outermost planet suggest that additional planets or minor bodies are present in the system.
In 2012, a partial transit of the second outermost planet by the outermost planet was reported. This was the first time a planet-planet transit in front of the star was detected. This allowed to determine the mutual inclination of the planets d and e to be 1.15°.