Upsilon Librae

Short description: Binary star in the constellation Libra

Upsilon Librae

Location of υ Librae (circled in red)

Observation data
Equinox J2000.0]] (ICRS)
Constellation | Libra
Right ascension |  15h 37m 01.45020s[1]
Declination | −28° 08′ 06.2926″[1]
Apparent magnitude (V) | 3.628[2]
Characteristics
Spectral type | K3 III[3]
U−B color index | +1.586[2]
B−V color index | +1.374[2]
Astrometry
Radial velocity (Rv)| −24.9±0.7[4] km/s
Proper motion (μ)|  RA: −12.82[1] mas/yr
Dec.: −4.15[1] mas/yr
Parallax (π)| 14.58 ± 0.19[1] mas
Distance| 224 ± 3 ly
(68.6 ± 0.9 pc)
Absolute magnitude (MV)| −0.28[5]
Details[6]
Mass| 1.67 M☉
Radius| 31.5[7] R☉
Luminosity| 309 L☉
Surface gravity (log g)| 1.58 cgs
Temperature| 4,135±20 K
Metallicity [Fe/H]| −0.02 dex
Age| 3.14 Gyr
Other designations

υ Lib, 39 Lib, CD−27°10464, FK5 579, HD 139063, HIP 76470, HR 5794, SAO 183619[8]

Database references
SIMBAD| data

Upsilon Librae (υ Lib, υ Librae) is the Bayer designation for a double star[9] in the zodiac constellation Libra. With an apparent visual magnitude of 3.628,[2] it is visible to the naked eye. The distance to this star, based upon an annual parallax shift of 14.58,[1] is around 224 light years. It has a magnitude 10.8 companion at an angular separation of 2.0 arc seconds along a position angle of 151°, as of 2002.[10]

The brighter component is an evolved K-type giant star with a stellar classification of K3 III.[3] The measured angular diameter, after correction for limb darkening, is 4.27±0.05 mas.[11] At the estimated distance of the star, this yields a physical size of about 31.5 times the radius of the Sun.[7] It has 1.67 times the mass of the Sun and radiates 309 times the solar luminosity from its outer atmosphere at an effective temperature of 4,135 K.[6] The star is about three billion years old.[6]

Upsilon Librae will be the brightest star in the night sky in about 2.3 million years,[12] and will peak in brightness with an apparent magnitude of −0.46, or more than 40 times its present-day brightness.[12]

This star was originally designated by Bayer as Omicron Scorpii, but it was reassigned to Libra as Upsilon Librae.[13]: 196, 278 The star now known as Omicron Scorpii was a reinterpretation of o (Latin letter o) Scorpii, a designation given by Lacaille.

## References

1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V.
2. ↑ 2.0 2.1 2.2 2.3 Celis S., L. (October 1975), "Photoelectric photometry of late-type variable stars", Astronomy and Astrophysics Supplement Series 22: 9–17, Bibcode: 1975A&AS...22....9C.
3. ↑ 3.0 3.1 Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode: 1982mcts.book.....H
4. ↑ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: 14, doi:10.1051/0004-6361/201219219, A61, Bibcode: 2012A&A...546A..61D.
5. ↑ Ryon, Jenna et al. (August 2009), "Comparing the Ca ii H and K Emission Lines in Red Giant Stars", Publications of the Astronomical Society of the Pacific 121 (882): 842, doi:10.1086/605456, Bibcode: 2009PASP..121..842R.
6. ↑ 6.0 6.1 6.2 Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 23, doi:10.1088/0004-6256/150/3/88, 88, Bibcode: 2015AJ....150...88L.
7. ↑ 7.0 7.1 Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1, https://books.google.com/books?id=OvTjLcQ4MCQC&pg=PA41. The radius (R*) is given by:

2⋅R*=(68.6⋅4.27⋅10−3) AU0.0046491 AU/R⨀≈63.0⋅R⨀
8. ↑ "ups Lib". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=ups+Lib.
9. ↑ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.
10. ↑ Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466, doi:10.1086/323920, Bibcode: 2001AJ....122.3466M
11. ↑ Richichi, A. et al. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics 431 (2): 773–777, doi:10.1051/0004-6361:20042039, Bibcode: 2005A&A...431..773R.
12. ↑ 12.0 12.1 Tomkin, Jocelyn (April 1998). "Once and Future Celestial Kings". Sky and Telescope 95 (4): 59–63. Bibcode: 1998S&T....95d..59T. based on computations from HIPPARCOS data. (The calculations exclude stars whose distance or proper motion is uncertain.) PDF
13. ↑ Wagman, Morton (2003). Lost Stars. McDonald & Woodward. ISBN 0939923785.

* v
* t
* e

Stars of Libra

Bayer|

* α1
* α2 (Zubenelgenubi)
* β (Zubeneschamali)
* γ (Zubenelhakrabi)
* δ (Zuben Elakribi)
* ε
* ζ1
* ζ4
* η
* θ
* ι1
* ι2
* κ
* λ
* μ
* ν
* ξ1
* ξ2
* ο
* σ (Brachium)
* τ
* υ

Flamsteed|

* 2
* 3
* 4
* 5
* 10
* 11
* 12
* 16
* 17
* 18
* 22
* 23
* 26
* 28
* 30
* 33
* 36
* 37
* 41
* 42
* 47
* 48
* 49
* 50
* 30 Ser

Variable|

* UZ
* VZ
* EH
* ES
* FY
* GW
* GZ (ζ2)
* GX
* HI
* HM
* HO
* HP
* HR
* IU
* KU
* KX

HR|

* 5390
* 5393
* 5438
* 5455
* 5499
* 5504
* 5513
* 5518
* 5521
* 5522
* 5583
* 5590
* 5620
* 5641
* 5655
* 5658
* 5669
* 5678
* 5707
* 5720
* 5749
* 5750 (ζ3)
* 5756
* 5762
* 5765
* 5801
* 5806
* 5809
* 5810
* 5816
* 5819
* 5847
* 5856
* 5866
* 5896
* 5927

HD|

* 126363
* 132953
* 133131
* 134439
* 134440
* 134758
* 136646
* 137798
* 139139
* 140283
* 141569
* 141937

Other|

* HE 1523-0901
* 2MASS 1507−1627
* WISE 1541−2250

* List

0.00

(0 votes)

Original source: https://en.wikipedia.org/wiki/Upsilon Librae. Read more

|

Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:Upsilon_Librae&oldid=4213728"
*[RA:]: Right Ascension
*[Dec.:]: Declination
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template