# 23 Librae b > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/23_Librae_b > Markdown URL: https://mediated.wiki/source/23_Librae_b.md > Source: https://en.wikipedia.org/wiki/23_Librae_b > Source revision: 1353014634 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) Extrasolar planet in the constellation Libra 23 Librae b 23 Librae b (min. mass ~1.59 MJ) as seen with Celestia Discovery[1][2] Discovered by California and Carnegie Planet Search Discovery site W. M. Keck Observatory Discovery date November 1, 1999 Detection method Doppler spectroscopy Orbital characteristics Semi-major axis 0.81 ± 0.02 AU (121.2 ± 3.0 million km) Eccentricity 0.233 ± 0.002 Orbital period (sidereal) 258.19 ± 0.07 d 0.7069 y Time of periastron 2,450,331.7 ± 2.2 Argument of periastron 358.3 ± 3.7 Semi-amplitude 49.52 ± 0.57 Star 23 Librae **23 Librae b** (23 Lib b), also known as HD 134987 b, is an [extrasolar](/source/Exoplanet) [Jovian planet](/source/Jovian_planet) discovered in November 1999 orbiting the star [23 Librae](/source/23_Librae). It orbits in its star's [habitable zone](/source/Habitable_zone).[1][2][3] As of 1999, the planet was known to have at least 1.5 times [Jupiter's mass](/source/Jupiter_mass). The planet orbits 23 Librae at an average distance of 0.82 [AU](/source/Astronomical_unit), which is between that of [Venus](/source/Venus) and the [Earth](/source/Earth) in the [Solar System](/source/Solar_System).[4] ## See also - [List of exoplanets discovered before 2000](/source/List_of_exoplanets_discovered_before_2000) ## References 1. ^ [***a***](#cite_ref-Keck_1-0) [***b***](#cite_ref-Keck_1-1) ["Astronomers discover six new planets orbiting nearby stars"](http://www.keckobservatory.org/astronomers_discover_six_new_planets_orbiting_nearby_stars/) (Press release). Kamuela, HI: W. M. Keck Observatory. November 1, 1999. Retrieved December 19, 2017. 1. ^ [***a***](#cite_ref-Vogt2000_2-0) [***b***](#cite_ref-Vogt2000_2-1) [Vogt, Steven S.](/source/Steven_S._Vogt); [Marcy, Geoffrey W.](/source/Geoffrey_Marcy); [Butler, R. Paul](/source/R._Paul_Butler); Apps, Kevin (2000). ["Six New Planets from the Keck Precision Velocity Survey"](https://doi.org/10.1086%2F308981). *The Astrophysical Journal*. **536** (2): 902–914. [arXiv](/source/ArXiv_(identifier)):[astro-ph/9911506](https://arxiv.org/abs/astro-ph/9911506). [Bibcode](/source/Bibcode_(identifier)):[2000ApJ...536..902V](https://ui.adsabs.harvard.edu/abs/2000ApJ...536..902V). [doi](/source/Doi_(identifier)):[10.1086/308981](https://doi.org/10.1086%2F308981). 1. **[^](#cite_ref-Butler2006_3-0)** [Butler, R. P.](/source/R._Paul_Butler); Wright, J. T.; [Marcy, G. W.](/source/Geoffrey_Marcy); Fischer, D. A.; [Vogt, S. S.](/source/Steven_S._Vogt); [Tinney, C. G.](/source/Chris_Tinney); Jones, H. R. A.; Carter, B. D.; Johnson, J. A.; McCarthy, C.; Penny, A. J. (2006). ["Catalog of Nearby Exoplanets"](https://doi.org/10.1086%2F504701). *The Astrophysical Journal*. **646** (1): 505–522. [arXiv](/source/ArXiv_(identifier)):[astro-ph/0607493](https://arxiv.org/abs/astro-ph/0607493). [Bibcode](/source/Bibcode_(identifier)):[2006ApJ...646..505B](https://ui.adsabs.harvard.edu/abs/2006ApJ...646..505B). [doi](/source/Doi_(identifier)):[10.1086/504701](https://doi.org/10.1086%2F504701). 1. **[^](#cite_ref-Jones2010_4-0)** Jones, Hugh R. A.; [Butler, R. Paul](/source/R._Paul_Butler); [Tinney, C. G.](/source/Chris_Tinney); O'Toole, Simon; Wittenmyer, Rob; Henry, Gregory W.; Meschiari, Stefano; [Vogt, Steve](/source/Steven_S._Vogt); Rivera, Eugenio; [Laughlin, Greg](/source/Gregory_P._Laughlin); Carter, Brad D.; Bailey, Jeremy; Jenkins, James S. (2010). ["A long-period planet orbiting a nearby Sun-like star"](https://doi.org/10.1111%2Fj.1365-2966.2009.16232.x). *Monthly Notices of the Royal Astronomical Society*. **403** (4): 1703–1713. [arXiv](/source/ArXiv_(identifier)):[0912.2716](https://arxiv.org/abs/0912.2716). [Bibcode](/source/Bibcode_(identifier)):[2010MNRAS.403.1703J](https://ui.adsabs.harvard.edu/abs/2010MNRAS.403.1703J). [doi](/source/Doi_(identifier)):[10.1111/j.1365-2966.2009.16232.x](https://doi.org/10.1111%2Fj.1365-2966.2009.16232.x). v t e 23 Librae system Stars 23 Librae Planets 23 Librae b 23 Librae c This exoplanet related article is a stub. You can help Wikipedia by adding missing information. - [v](https://en.wikipedia.org/wiki/Template:Exoplanet-planet-stub) - [t](/source/Template_talk%3AExoplanet-planet-stub) - [e](https://en.wikipedia.org/wiki/Special:EditPage/Template:Exoplanet-planet-stub) --- Adapted from the Wikipedia article [23 Librae b](https://en.wikipedia.org/wiki/23_Librae_b) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/23_Librae_b?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.