HD 117440
Template:Short description Template:About-distinguish
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Centaurus[1] |
| Right ascension | Template:RA[2] |
| Declination | Template:DEC[2] |
| Apparent magnitude (V) | 4.64 + 5.03[3] |
| Characteristics | |
| Spectral type | G7III + G9III[4] |
| U−B Template:Engvar | +1.03 |
| B−V Template:Engvar | +1.17 |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | Script error: No such module "val".[5] km/s |
| Proper motion (μ) | RA: Script error: No such module "val".[2] mas/yr Dec.: Script error: No such module "val".[2] mas/yr |
| Parallax (π) | 3.60±0.49 mas[2] |
| Distance | approx. Template:Rnd ly (approx. Template:Rnd pc) |
| Orbit[6] | |
| Period (P) | Script error: No such module "val". yr |
| Semi-major axis (a) | Script error: No such module "val".″ |
| Eccentricity (e) | Script error: No such module "val". |
| Inclination (i) | Script error: No such module "val".° |
| Longitude of the node (Ω) | Script error: No such module "val".° |
| Periastron epoch (T) | Script error: No such module "val". B |
| Argument of periastron (ω) (secondary) | Script error: No such module "val".° |
| Details | |
| Mass | Script error: No such module "val".[7] Template:Solar mass |
| Surface gravity (log g) | 1.86[8] cgs |
| Temperature | 4,683[8] K |
| Metallicity [Fe/H] | −0.36[8] dex |
| Rotational velocity (v sin i) | 4.5[8] km/s |
| Age | Script error: No such module "val".[7] Myr |
| Metallicity [Fe/H] | {{{metal_fe2}}} dex |
| Other designations | |
| Template:Odlist | |
| Database references | |
| SIMBAD | data |
Script error: No such module "Check for unknown parameters".
HD 117440, also known by its Bayer designation d Centauri, is a binary star[9] system in the southern constellation of Centaurus. It is visible to the naked eye with a combined apparent visual magnitude of 3.90.[1] The distance to this system is approximately 900 light years based on parallax measurements.[2] It is drifting closer to the Sun with a radial velocity of −2 km/s.[5]
A companion star was first reported by T. J. J. See in 1897 at an angular separation of Script error: No such module "val". from the primary.[3] Orbital elements for the pair were published by W. S. Finsen in 1962[10] then updated in 1964, yielding an orbital period of 83.1 years with a semimajor axis of Script error: No such module "val". and an eccentricity of 0.52.[6] Both components are evolved G-type giant stars with a yellow, Sun-like hue. The primary, component A, has an apparent magnitude of +4.64, while the secondary, component B, has an apparent magnitude of +5.03.[10]
References
<templatestyles src="Reflist/styles.css" />
- ↑ a b Template:Cite XHIP
- ↑ a b c d e f Script error: No such module "Citation/CS1". Vizier catalog entry
- ↑ a b Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ a b Script error: No such module "Citation/CS1".
- ↑ a b Script error: No such module "Citation/CS1".
- ↑ a b Script error: No such module "Citation/CS1".
- ↑ a b c d Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ a b Script error: No such module "Citation/CS1".
Script error: No such module "Check for unknown parameters".