49 Librae

{{Starbox observe

| epoch = J2000

| constell = Libra

| ra = {{RA|16|00|19.61087}}

| dec = {{DEC|−16|32|00.5483}}

| appmag_v = 5.47

}}

{{Starbox character

| type = main sequence

| class = F8 V

| b-v = +0.52

| u-b = +0.03

| variable =

}}

{{Starbox astrometry

| radial_v = {{val|−20.1|4.0}}

| prop_mo_ra = −644.387

| prop_mo_dec = −360.803

| parallax = 34.2281

| p_error = 0.1906

| parallax_footnote =

| absmag_v = 2.89

}}

{{Starbox orbit

| reference =

| period_unitless = {{Val|1142.4|1.1|fmt=commas|u=days}}

| axis_unitless = ≥ {{Val|59.53|0.244|ul=Gm}}

| eccentricity = {{Val|0.110|0.012}}

| inclination = {{Val|143.0|2.0}}

| node = {{Val|163.5|2.8}}

| periastron = {{Val|57025|22|ul=MJD}}

| periarg = {{Val|69.4|7.4}}

| k1 = {{Val|3.847|0.051}}

}}

{{Starbox detail

| component1 = 49 Lib A

| mass = 1.4

| radius = {{Val|1.86|0.05|0.04}}

| gravity = 4.14

| metal_fe = −0.02

| temperature = 6,237

| luminosity = {{Val|4.74|0.03}}

| rotational_velocity = {{Val|9.6|1.0}}

| rotation =

| age_gyr = 12

| component2 = 49 Lib B

| mass2 = 0.45

}}

{{Starbox catalog

| names = {{odlist| F=49 Lib | BD=−16°4196 | FK5=1419 | GJ=3931 | HD=143333 | HIP=78400 | HR=5954 | SAO=159625 | WDS=J16003-1632A }}

}}

{{Starbox reference

| Simbad = 49+Lib

}}

49 Librae is the Flamsteed designation for a binary star system in the Zodiac constellation of Libra. It has an apparent visual magnitude of 5.47, making it faintly visible to the naked eye from dark suburban skies as a dim, yellow-white hued star. The system is located 95 light years away from the Sun, based on parallax, but is drifting closer with a radial velocity of −20 km/s.

The variable nature of the velocity for 49 Librae was first noted by W. S. Adams in 1924. It is a single-lined spectroscopic binary with an orbital period of {{Convert|1142.4|days|years|disp=out|abbr=off}} and an eccentricity of 0.11. The primary component has a stellar classification of F8 V or F9 V, indicating it is an F-type main-sequence star. It has an estimated 1.4 times the mass of the Sun, while the companion only has 0.4 solar masses. The system is a source for radio and X-ray emissions, which may be coming from the secondary companion.

References

{{Reflist|refs=

{{citation | postscript=.

| title=Spectroscopic Orbits for 15 Late-type Stars

| last1=Willmarth | first1=Daryl W. | last2=Fekel | first2=Francis C.

| last3=Abt | first3=Helmut A. | last4=Pourbaix | first4=Dimitri

| display-authors=1 | journal=The Astronomical Journal

| doi=10.3847/0004-6256/152/2/46 | bibcode=2016AJ....152...46W | s2cid=53648490

| url=https://dipot.ulb.ac.be/dspace/bitstream/2013/236718/3/Willmarth_2016_AJ_152_46.pdf | doi-access=free

}}

{{citation

| last1=Balachandran | first1=Suchitra

| title=Lithium depletion and rotation in main-sequence stars

| journal=Astrophysical Journal, Part 1 | volume=354

| date=May 1, 1990 | pages=310–332

| doi=10.1086/168691 | bibcode=1990ApJ...354..310B

| postscript=. }}

{{citation

| display-authors=1

| last1=Nordström | first1=B.

| last2=Andersen | first2=J.

| last3=Holmberg | first3=J.

| title=The Geneva-Copenhagen survey of the Solar neighbourhood. II. New uvby calibrations and rediscussion of stellar ages, the G dwarf problem, age-metallicity diagram, and heating mechanisms of the disk

| journal=Astronomy & Astrophysics | pages=519–537 | volume=475 | issue=2

|date=November 2007

| arxiv=0707.1891 | bibcode=2007A&A...475..519H

| doi=10.1051/0004-6361:20077221 | s2cid=119054949 | postscript=.

}}

{{citation

| last=Nicolet | first=B.

|date=October 1978

| title=Photoelectric photometric Catalogue of homogeneous measurements in the UBV System

| journal=Astronomy and Astrophysics Supplement Series

| volume=34 | pages=1–49 | bibcode=1978A&AS...34....1N

| postscript=. }}