14 Herculis b
{{Short description|Extrasolar planet in the constellation Hercules}}
{{Use dmy dates|date=April 2021}}
{{Infobox planet
| name = 14 Herculis b
| image = 14 Herculis b (Celestia).jpg
| image_size =
| image_alt =
| caption = The exoplanet 14 Herculis b as rendered by Celestia
| discoverer = Naef et al.; Butler et al.
| discovery_site = Switzerland
| discovered = 6 July 1998 (announced)
January 2003 (published)
| discovery_method = Doppler spectroscopy
| extrasolarplanet = yes
| pronounced =
| named_after =
| alt_names = HD 145675 b
| adjectives =
| epoch =
| apsis = astron
| aphelion =
| perihelion =
| semimajor = {{val|2.845|0.038|0.039|ul=AU}}
| eccentricity = {{val|0.371|0.003}}
| period = {{val|1767.56|0.22|ul=d}}
{{val|4.8393|0.0006|ul=yr}}
| synodic_period =
| avg_speed =
| mean_anomaly =
| mean_motion =
| inclination = {{val|147.3|2.2|2.7|u=deg}}
| angular_dist =
| asc_node = {{val|276|5|u=deg}}
| time_periastron = {{val|2451368.0|0.5|fmt=commas|ul=JD}}
| arg_peri = {{val|22.28|0.15|u=deg}}
| semi-amplitude = {{val|90.38|0.15|ul=m/s}}
| satellites =
| star = 14 Herculis
| mean_radius =
| flattening =
| surface_area =
| volume =
| mass = {{val|8.5|1.0|0.8|ul=Jupiter mass}}
| density =
| surface_grav =
| moment_of_inertia_factor =
| escape_velocity =
| rotation =
| sidereal_day =
| rot_velocity =
| axial_tilt =
| albedo =
| single_temperature =
| spectral_type =
}}
14 Herculis b or 14 Her b is an exoplanet approximately 58.4 light-years away in the constellation of Hercules. The planet was found orbiting the star 14 Herculis, with a mass that would make the planet a Jovian planet roughly the same size as Jupiter but much more massive. It was discovered in July 1998 by the Geneva Extrasolar Planet Search team.{{cite conference|author=Mayor, M.|title=Searching for giant planets at the Haute-Provence Observatory|conference=IAU Colloqu. 170|book-title=Precise Stellar Radial Velocities|editor= Hearnshaw, J. B.|editor2= Scarfe, C. D.|date=1998|publisher=ASP|location=San Francisco|display-authors=etal}} The discovery was formally published in 2003. At the time of discovery it was the extrasolar planet with the longest orbital period, though longer-period planets have subsequently been discovered.
Discovery
14 Herculis b was detected by measuring variations in its star's radial velocity as a result of the planet's gravity. This was done by making precise measurements of the Doppler shift of the spectrum of 14 Herculis. Prior to this analysis, another possible explanation of previous Doppler shift analysis included face-on spectroscopic binaries.
Orbit and mass
Preliminary astrometric measurements made by the Hipparcos satellite suggested that this planet has an orbital inclination of 155.3° with respect to plane of the sky, which would imply a true mass of 11.1 times that of Jupiter, close to the deuterium burning threshold that some astronomers use to define the distinction between a planet and a brown dwarf. However subsequent analysis suggests that the Hipparcos measurements were not precise enough to accurately determine the orbits.{{cite journal|bibcode=2001A&A...372..935P|title=Screening the Hipparcos-based astrometric orbits of sub-stellar objects|author=Pourbaix, D.|author2=Arenou, F.|name-list-style=amp|journal=Astronomy and Astrophysics|volume=372|issue=3|pages=935–944|date=2001|doi=10.1051/0004-6361:20010597|arxiv = astro-ph/0104412 |s2cid=378792 }} According to a 2008 paper, its inclination was being calculated via astrometry with Hubble, with publication expected by mid-2009.{{cite arXiv | title=HST FGS astrometry - the value of fractional millisecond of arc precision |class=astro-ph |eprint=0803.0296v1 |date=2008 | last1=Fritz Benedict | first1=G. | last2=McArthur | first2=Barbara E. | last3=Bean | first3=Jacob L.}}, for "HD 145675 b"
The inclination and true mass of 14 Herculis b were finally measured in 2021, using data from Gaia, and refined by further astrometric studies in 2022 and 2023. The inclination is 147.3°, and the true mass is {{Jupiter mass|8.5|link=y}}.
Direct imaging
Because of the wide separation between this planet and its host star, and the proximity of the 14 Herculis system to the Sun, it is a promising candidate for direct imaging of the planet, as the angular separation of the planet and host star will be large enough that the light from the planet and star might be spatially resolved. However, a search made using the adaptive optics CFHT 3.60m telescope on Mauna Kea did not make such a detection, confirming the object is not a star.
References
{{reflist|refs=
{{cite journal |last1=Butler |first1=R. Paul |display-authors=etal |date=January 2003 |title=Seven New Keck Planets Orbiting G and K Dwarfs |journal=The Astrophysical Journal |volume=582 |issue=1 |pages=455–466 |doi=10.1086/344570 |bibcode=2003ApJ...582..455B|doi-access=free }}
{{cite journal |last1=Feng |first1=Fabo |last2=Butler |first2=R. Paul |display-authors=etal |date=August 2022 |title=3D Selection of 167 Substellar Companions to Nearby Stars |journal=The Astrophysical Journal Supplement Series |volume=262 |issue=21 |page=21 |doi=10.3847/1538-4365/ac7e57 |arxiv=2208.12720 |bibcode=2022ApJS..262...21F |s2cid=251864022 |doi-access=free }}
{{cite journal |last1=Benedict |first1=G. F. |last2=McArthur |first2=B. E. |display-authors=etal |date=May 2023 |title=The 14 Her Planetary System: Companion Masses and Architecture from Radial Velocities and Astrometry |journal=The Astronomical Journal |volume= 166|issue= 1|page=27 |doi= 10.3847/1538-3881/acd93a|arxiv=2305.11753 |bibcode=2023AJ....166...27B |doi-access=free }}
}}
External links
- {{cite web |url=https://exoplanet.eu/catalog/14_her_b--77/ |title=Notes for Planet 14 Her b |author=Jean Schneider |date=2011 |work=Extrasolar Planets Encyclopaedia |access-date=30 September 2011}}
- {{cite web |url=http://www.solstation.com/stars2/14her.htm |title=14 Herculis |access-date=25 June 2008 |work=SolStation| archive-url= https://web.archive.org/web/20080719164703/http://www.solstation.com/stars2/14her.htm| archive-date= 19 July 2008 }}
{{14 Herculis}}
{{Sky|16|10|23.59|+|43|49|18.2|59}}
{{DEFAULTSORT:14 Herculis B}}
Category:Hercules (constellation)
Category:Exoplanets discovered in 1998