Chi Draconis
Template:Location mark Location of χ Draconis (circled) | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Draco |
| Right ascension | Template:RA[1] |
| Declination | Template:DEC[1] |
| Apparent magnitude (V) | 3.570[2] |
| Characteristics | |
| Spectral type | F7V / K0V[3] |
| U−B Template:Engvar | −0.06[4] |
| B−V Template:Engvar | +0.49[4] |
| Variable type | Suspected[5] |
| Astrometry | |
| Radial velocity (Rv) | +32.4[2] km/s |
| Proper motion (μ) | RA: +531.21[1] mas/yr Dec.: −349.71[1] mas/yr |
| Parallax (π) | 120.05±0.15 mas[3] |
| Distance | Template:Rnd ± Template:Rnd ly (Template:Rnd ± Template:Rnd pc) |
| Absolute magnitude (MV) | 4.04[2] |
| Orbit[6] | |
| Primary | χ Dra Aa |
| Companion | χ Dra Ab |
| 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". |
| Argument of periastron (ω) (secondary) | Script error: No such module "val".° |
| Details | |
| χ Dra Aa | |
| Mass | Script error: No such module "val".[3] Template:Solar mass |
| Radius | Script error: No such module "val".[3] Template:Solar radius |
| Luminosity | 1.86[3] Template:Solar luminosity |
| Temperature | Script error: No such module "val".[3] K |
| Metallicity [Fe/H] | −0.41[2] dex |
| Rotational velocity (v sin i) | 11[7] km/s |
| Age | 5.3[2] Gyr |
| χ Dra Ab | |
| Mass | Script error: No such module "val".[3] Template:Solar mass |
| Radius | Script error: No such module "val".[3] Template:Solar radius |
| Luminosity | 0.29[3] Template:Solar luminosity |
| Temperature | Script error: No such module "val".[3] K |
| Metallicity [Fe/H] | {{{metal_fe2}}} dex |
| Other designations | |
| χ Dra, 44 Dra, BD+72°839, FK5 695, Gl 713, HD 170153, HIP 89937, HR 6927, LHS 3379, LTT 15438, SAO 9087, NSV 10749[8] | |
| Database references | |
| SIMBAD | data |
Script error: No such module "Check for unknown parameters".
Chi Draconis (χ Dra, χ Draconis, Chi Draconis) is a magnitude 3.6 binary star in the constellation Draco. It also has the Flamsteed designation 44 Draconis. At a distance of 27 light-years, it is one of the 200 or so closest stars.[9]
Binary system
χ Draconis is a spectroscopic binary which has been resolved using speckle interferometry.[4] The primary is an F7 main sequence star. The spectral type of the companion cannot be determined directly with any accuracy, but is known to be between G8 and K2 and is assumed to be K0. The properties of the secondary suggest that it is also a main-sequence star. The separation of the two stars varies between about Script error: No such module "val". and Script error: No such module "val". during the eccentric 182-day orbit.[10]
The primary star has a mass fractionally higher than the Sun's, but is significantly larger and hotter resulting in it being 86% more luminous.[3] Its age is estimated to be about five billion years.[2]
The secondary only has about three-quarters the mass of the Sun and is both cooler and smaller. It is only about 29% as luminous.[3] It is calculated to be 2.13 magnitudes fainter than the primary, so it would be of sixth magnitude if visible alone.[11]
Visual companions
Multiple star catalogues list faint widely-separated visible companion stars: a 12th-magnitude star and a 14th-magnitude star about Script error: No such module "val". from χ Draconis, but only about Script error: No such module "val". from each-other.[12] Both have much smaller parallaxes than χ Draconis and are unrelated background objects.[13]
See also
References
<templatestyles src="Reflist/styles.css" />
- ↑ a b c d Script error: No such module "Citation/CS1".
- ↑ a b c d e f Script error: No such module "Citation/CS1".
- ↑ a b c d e f g h i j k l Script error: No such module "Citation/CS1". See p. 56, entry #15.
- ↑ a b c Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "Citation/CS1". Data available at https://gruze.org/10pc/ Template:Webarchive
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Template:Cite Gaia DR3
Script error: No such module "Check for unknown parameters".
External links
- ARICNS
- Chi Draconis 2 at SolStation.
- nStars database entry