Kepler-70
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cygnus |
| Right ascension | 19h 45m 25.47457s |
| Declination | +41° 05′ 33.8822″ |
| Apparent magnitude (V) | 14.87 |
| Characteristics | |
| Spectral type | sdB |
| Apparent magnitude (U) | 13.80 |
| Apparent magnitude (B) | 14.71 |
| Apparent magnitude (R) | 15.43 |
| Apparent magnitude (I) | 15.72 |
| Apparent magnitude (J) | 15.36 |
| Apparent magnitude (H) | 15.59 |
| Astrometry | |
| Proper motion (μ) | RA: +7.217(29) mas/yr Dec.: −3.148(30) mas/yr |
| Parallax (π) | 0.9086±0.0247 mas |
| Distance | 3,590 ± 100 ly (1,100 ± 30 pc) |
| Absolute magnitude (MV) | +4.21±0.11 |
| Details | |
| Mass | 0.496±0.002 M☉ |
| Radius | 0.203±0.007 R☉ |
| Luminosity | 22.9±3.1 L☉ |
| Surface gravity (log g) | 5.552±0.041 cgs or 5.52±0.03 cgs |
| Temperature | 27,730±270 K or 28,050±470 K |
| Age | 18.4±1.0 Myr |
| Other designations | |
| 2MASS J19452546+4105339, KIC 5807616, KOI-55, UCAC2 46165657, UCAC3 263-170867, USNO-B1.0 1310-00349976 | |
| Database references | |
| SIMBAD | data |
| KIC | data |
Kepler-70, also known as KIC 5807616 and KOI-55, is a star about 3,600 light-years (1,100 parsecs) away in the constellation Cygnus, with an apparent visual magnitude of 14.87. This is too faint to be seen with the naked eye; viewing it requires a telescope with an aperture of 40 cm (20 in) or more.
A subdwarf B star, Kepler-70 passed through the red giant stage some 18.4 million years ago. In its present-day state, it is fusing helium in its core. Once it runs out of helium it will contract to form a white dwarf. It has a relatively small radius of about 0.2 times the Sun's radius; white dwarfs are generally much smaller. The star may be host to a planetary system with two planets, although later research indicates that this is not in fact the case.