- Source: KIC 9970396
KIC 9970396 is an eclipsing binary system located in the northern constellation of Cygnus about 3,290 light-years (1,010 parsecs) distant. The system consists of a red-giant branch star and an F-type main-sequence star. The two stars orbit each other every 235 days (0.64 years) at a mean distance of 207.92±0.73 R☉ (0.9669±0.0034 AU), almost the same as Earth's distance from the Sun.
The system was given the Kepler Object of Interest designation KOI-7606 as a planetary candidate, but has been marked a false positive since the dips in the light curve are caused by an eclipsing stellar companion rather than a transiting exoplanet.
Stellar components
= KIC 9970396A
=KIC 9970396A is a pulsating red giant currently in the red-giant branch, past the first dredge-up event and approaching the red giant bump. The star displays solar-like oscillations caused by turbulent convection near the surface. Since the star has used up all of its hydrogen within its core, the core now consists mostly of helium, with a mass of 0.229 M☉, that is 19% of the star's entire mass, and a radius of 0.03055 R☉. Its age is estimated at 6.13±0.19 billion years, about 1.5 billion years older than the Solar System (4.568 Gyr).
= KIC 9970396B
=KIC 9970396B is a late F-type star almost identical in mass to the Sun but slightly larger and hotter. Its mass is slightly smaller than the red giant primary, thus a possible scenario for the system is that the two stars formed together and the more massive primary star evolved past the main sequence first.
Its stellar parameters, alongside those of the red giant, were precisely measured using a combination of Kepler photometry and spectroscopic observations.
References
Kata Kunci Pencarian:
- KIC 9970396
- Tabby's Star
- Messier 39
- Kepler-70
- Deneb
- Egg Nebula
- Kepler-186
- V1974 Cygni
- Epsilon Cygni
- Kepler-452
