Iota Coronae Borealis
Binary star system in the constellation Corona Borealis
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Iota Coronae Borealis, Latinized from ι Coronae Borealis, is a binary star[6] system in the constellation Corona Borealis. It is visible to the naked eye with a combined apparent visual magnitude of is 4.96.[2] Based upon an annual parallax shift of 8.8 mas as seen from the Earth, it is located about 372 light years from the Sun.
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Corona Borealis |
| Right ascension | 16h 01m 26.56492s[1] |
| Declination | +29° 51â² 03.8194â³[1] |
| Apparent magnitude (V) | 4.96[2] |
| Characteristics | |
| Evolutionary stage | main sequence[1] |
| Spectral type | A0 IIIp(HgMnEu)s[3] |
| UâB color index | â0.15[2] |
| BâV color index | â0.06[2] |
| Astrometry | |
| Radial velocity (Rv) | â20.8±0.4[4] km/s |
| Proper motion (μ) | RA: â38.817[1] mas/yr Dec.: â7.016[1] mas/yr |
| Parallax (Ï) | 8.7701±0.0857 mas[1] |
| Distance | 372 ± 4 ly (114 ± 1 pc) |
| Absolute magnitude (MV) | +0.08[5] |
| Orbit[6] | |
| Period (P) | 35.474 d |
| Eccentricity (e) | 0.56 |
| Periastron epoch (T) | 2441566.96 JD |
| Argument of periastron (Ï) (secondary) | 156° |
| Semi-amplitude (K1) (primary) | 2.3 km/s |
| Details | |
| ι CrB A | |
| Luminosity | 90[7] Lâ |
| Surface gravity (log g) | 3.84±0.16[8] cgs |
| Temperature | 10,727±278[8] K |
| Metallicity [Fe/H] | â0.01±0.12[8] dex |
| Rotational velocity (v sin i) | 18[9] km/s |
| Other designations | |
| ι CrB, 14 CrB, BD+30°2738, HD 143807, HIP 78493, HR 5971, SAO 84152[10] | |
| Database references | |
| SIMBAD | data |
This is a single-lined spectroscopic binary with an orbital period of 35.5 days and an eccentricity of 0.56.[6] The visible member, component A, has a stellar classification of A0 IIIp(HgMnEu)s,[3] indicating it is a chemically peculiar mercury-manganese star with narrow absorption lines. The secondary member, component B, appears to be an A-type star.[11]