Delta Boötis

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Short description

δ Boötis
Template:Location mark
Location of δ Boötis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes[1]
A
Right ascension Template:RA[2]
Declination Template:DEC[2]
Apparent magnitude (V) 3.482[3]
B
Right ascension Template:RA[4]
Declination Template:DEC[4]
Apparent magnitude (V) 7.81[5]
Characteristics
A
Spectral type G8 III[6]
U−B Template:Engvar +0.656[3]
B−V Template:Engvar +0.951[3]
B
Spectral type G0 V[5]
U−B Template:Engvar +0.02[5]
B−V Template:Engvar +0.59[5]
Astrometry
A
Radial velocity (Rv)Script error: No such module "val".[7] km/s
Proper motion (μ) RA: +84.383 mas/yr[2]
Dec.: −111.591 mas/yr[2]
Parallax (π)27.0746±0.1256 mas[2]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)+0.700[8]
B
Radial velocity (Rv)Script error: No such module "val".[4] km/s
Proper motion (μ) RA: +82.918 mas/yr[9]
Dec.: −110.075 mas/yr[9]
Parallax (π)27.1573±0.0178 mas[9]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)+4.96[1]
Details
A
Mass1.5[10] Template:Solar mass
RadiusScript error: No such module "val".[11] Template:Solar radius
LuminosityScript error: No such module "val".[12] Template:Solar luminosity
Surface gravity (log g)Script error: No such module "val".[12] cgs
TemperatureScript error: No such module "val".[12] K
Metallicity [Fe/H]Script error: No such module "val".[12] dex
Rotational velocity (v sin i)3.6[13] km/s
B
Mass0.98[10] Template:Solar mass
RadiusScript error: No such module "val".[4] Template:Solar radius
Luminosity0.87[10] Template:Solar luminosity
TemperatureScript error: No such module "val".[10] K
Metallicity [Fe/H]{{{metal_fe2}}} dex
Age3.09[10] Gyr
Other designations
Template:Odlist[14]
A: Template:Odlist[14]
B: Template:Odlist[15]
Database references
SIMBADA
B

Script error: No such module "Check for unknown parameters".

Delta Boötis is a double star in the northern constellation of Boötes, forming the easternmost member of the constellation's kite-shaped asterism of brighter stars.[16] Its name is a Bayer designation that is Latinized from δ Boötis, and abbreviated Delta Boo or δ Boo. Based upon parallax measurements, it is located at a distance of approximately Script error: No such module "convert". from the Earth.[2] The apparent visual magnitude of this star is 3.5,[3] making it visible to the naked eye even during a Full Moon. The magnitude 7.81[5] companion can be viewed in binoculars or a small telescope.[16]

Properties

File:Delta Bootis.jpg
δ Boötis in optical light

This system consists of a pair of stars located in physical proximity to each other and sharing a similar motion through space, suggesting that they may form a binary star system. Based upon their angular separation and their distance, they have a projected separation of 3,800 Astronomical Units (AU). If they are gravitationally bound to each other, the orbital period of the system would be at least 120,000 years.[17]

The brighter member of the pair has a stellar classification of G8 III,[6] indicating that it has exhausted the supply of hydrogen at its core and evolved into a giant star. It now has a radius more than eleven times the radius of the Sun.[11] Compared to the Sun, this star appears deficient in elements other than hydrogen and helium—what astronomers term the star's metallicity. The outer envelope of this star has an effective temperature of 4,810 K,[12] which is what gives it the characteristic yellow hue of a G-type star.[18]

The secondary component has a stellar classification of G0 V,[5] which suggests it is a main sequence star that may be similar in physical properties to the Sun. The apparent visual magnitude of this star is 7.81,[5] making it much less luminous than the primary component.[19]

Nomenclature

This star is sometimes called Princeps Template:IPAc-en, meaning prince or prime in Latin.[20] The origin of this name is unclear, although it usually appears in an astrological context.[21][22]

In Chinese, Script error: No such module "Lang". (Script error: No such module "Lang".), meaning Seven Excellencies, refers to an asterism consisting of δ Boötis, 42 Herculis, τ Herculis, φ Herculis, χ Herculis, ν1 Boötis and μ1 Boötis.[23] Consequently, the Chinese name for δ Boötis itself is Script error: No such module "Lang". (Script error: No such module "Lang"., Template:Langx.)[24]

References

<templatestyles src="Reflist/styles.css" />

  1. ↑ a b Template:Cite XHIP
  2. ↑ a b c d e Template:Cite DR3
  3. ↑ a b c d Script error: No such module "citation/CS1".
  4. ↑ a b c d Template:Cite Gaia DR2
  5. ↑ a b c d e f g Script error: No such module "citation/CS1".
  6. ↑ a b Script error: No such module "citation/CS1".
  7. ↑ Script error: No such module "citation/CS1".
  8. ↑ Script error: No such module "citation/CS1".
  9. ↑ a b Template:Cite Gaia DR3
  10. ↑ a b c d e Script error: No such module "citation/CS1".
  11. ↑ a b Script error: No such module "citation/CS1".
  12. ↑ a b c d e Script error: No such module "citation/CS1". Delta Boo's database entry at VizieR.
  13. ↑ Script error: No such module "citation/CS1".
  14. ↑ a b Template:Cite simbad
  15. ↑ Template:Cite simbad
  16. ↑ a b Script error: No such module "citation/CS1".
  17. ↑ Script error: No such module "citation/CS1".
  18. ↑ Script error: No such module "citation/CS1".
  19. ↑ The actual brightness ratio is given by 2.512Δm, where Δm is the difference in magnitude. For this pair, Δm = –4.33, so the ratio is 2.512−4.33 = 0.019. Hence the secondary component is 1.9% as bright as the primary.
  20. ↑ Template:OED
  21. ↑ Script error: No such module "citation/CS1".
  22. ↑ Script error: No such module "citation/CS1".
  23. ↑ Template:In lang 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, Template:ISBN.
  24. ↑ Template:In lang AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 6 月 26 日 Template:Webarchive

Script error: No such module "Check for unknown parameters".

External links

Template:Stars of Boötes

Retrieved from "http://debianws.lexgopc.com/wiki143/index.php?title=Delta_Boötis&oldid=2018655"