| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Cygnus |
| Right ascension | 19h 53m 17.811s[1] |
| Declination | +42° 23′ 18.52″[1] |
| Apparent magnitude (V) | 10.715[2] |
| Characteristics | |
| Spectral type | A1V[3] |
| B−V color index | 0.154[2] |
| Details | |
| Mass | 2.22+0.10 −0.14[3] M☉ |
| Radius | 1.90+0.04 −0.05[3] R☉ |
| Luminosity | 25.6 ± 2.4[3] L☉ |
| Temperature | 9400 ± 150[3] K |
| Other designations | |
|
KIC 6889235, 2MASS J19531781+4223185, GSC2.3 N2J3000844
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KOI-74 (KIC 6889235 ) is an eclipsing binary star in the constellation of Cygnus. The primary star is an A-type main sequence star with a temperature of 9,400 K (9,130 °C; 16,460 °F). It lies in the field of view of the Kepler Mission and was determined to have a companion object in orbit around it which is smaller and hotter than the main star.[4]
KOI-74b is a hot compact object orbiting KOI-74. It was discovered in 2010 by the Kepler Mission and came to attention because of its small size (its radius is only 4.3% of the solar radius) and high temperature of 13,000 K (12,700 °C; 22,900 °F).[4] The orbit of KOI-74b around the main star takes 5.18875 days to complete. Analysis of relativistic boosting of light in the Kepler data indicates that it is likely to be a low mass white dwarf star of approximately 0.22 solar masses, resulting from an earlier phase of mass transfer in a binary system when the object underwent its giant phase.[3]