14 Herculis c

{{Short description|Extrasolar planet in the constellation Hercules}}

{{Infobox planet

| name = 14 Herculis c

| image = File:14 Herculis c (NIRCam).png

| caption = Direct image of 14 Herculis c taken with the James Webb Space Telescope. Its host star is blocked by a coronagraph.

| discovery_ref =

| discoverer = Goździewski et al.; Rosenthal et al.

| discovery_site = Observatoire de Haute-Provence, Keck & AFP

| discovered = 17 November 2005 (candidate)
2 July 2021 (confirmed)

| discovery_method = Doppler spectroscopy

| extrasolarplanet = yes

| alt_names = HD 145675 c

| orbit_ref =

| apsis = astron

| semimajor = {{val|20.0|12.0|4.9|ul=AU}}
{{val|28.1|6.4|6.8|u=AU}}

| eccentricity = {{val|0.64|0.06|0.10}}

| period = {{val|52160|1030|fmt=commas}} days
({{val|142.8|2.8}} years)

| inclination = {{val|111.9|5.4|5.5|u=deg}}

| asc_node = {{val|205.1|7.448|10.31|u=deg}}

| time_periastron = {{val|2451779|33|fmt=commas|ul=JD}}

| arg_peri = {{val|172.5|4.011|4.584|u=deg}}

| semi-amplitude = {{val|50.8|0.4|ul=m/s}}

| star = 14 Herculis

| physical_ref =

| mass = {{val|7.9|1.6|1.2|ul=Jupiter mass}}

| mean_radius = {{val|1.03|0.01|ul=Jupiter radius}}

| single_temperature = {{convert|275|K|C F|lk=in}}

| surface_grav = {{val|4.25|0.15|ul=cgs}}

}}

14 Herculis c or 14 Her c is the outermost of two known exoplanets orbiting the star 14 Herculis, approximately 58.4 light-years away in the constellation of Hercules. The planet has a mass that would make it a gas giant roughly the same size as Jupiter but much more massive.

Discovery

14 Herculis c was discovered by the radial velocity method. Its discovery was first reported in 2005 (published in 2006), using data from the ELODIE Planet Search survey. It remained a planet candidate until its existence was securely confirmed in 2021.

According to a 2007 analysis, the existence of a second planet in the 14 Herculis system was "clearly" supported by the evidence, but the planet's parameters were not precisely known. It may be in a 4:1 resonance with the inner planet 14 Herculis b.

The inclination and true mass of 14 Herculis c were measured in 2021, using data from Gaia, and refined by further astrometric studies in 2022 and 2023, as well by a 2025 study using James Webb Space Telescope astrometry. The inclination is 116°, corresponding to a true mass of {{Jupiter mass|7.1|link=y}}.

Direct imaging

The planet was directly imaged with the James Webb Space Telescope's NIRCam instrument in 2025. The observations determined a temperature of {{convert|275|K|C|lk=in}}, making it one of the coldest exoplanets directly imaged. They also re-measured its orbital elements, finding it to be closer to the star, at around 15 AU, on a highly eccentric orbit, as well as measuring its orbital inclination, finding it to be misaligned with 14 Herculis b by 40°. At wavelengths of 4.4 μm, its apparent magnitude is fainter than expected, hinting at disequilibrium chemistry and/or water ice clouds.{{Cite web |title=Frigid Exoplanet in Strange Orbit Imaged by NASA's Webb |url=https://webbtelescope.org/contents/news-releases/2025/news-2025-125 |access-date=2025-06-10 |website=Webb |language=en}}

See also

References

{{reflist|refs=

{{cite journal |bibcode=2006ApJ...645..688G |author=Goździewski, K. |author2=Konacki, M. |author3=Maciejewski, A. J.|title=Orbital Configurations and Dynamical Stability of Multiplanet Systems around Sun-like Stars HD 202206, 14 Herculis, HD 37124, and HD 108874|journal=The Astrophysical Journal|volume=645|issue=1|pages=688–703|date=2006|doi=10.1086/504030|arxiv = astro-ph/0511463 |s2cid=15012577 |url=http://authors.library.caltech.edu/5547/1/GOZapj06.pdf}}

{{cite journal |bibcode=2007ApJ...654..625W |author=Wittenmyer, R. A. |author2=Endl, M. |author3=Cochran, W. D.|title=Long-Period Objects in the Extrasolar Planetary Systems 47 Ursae Majoris and 14 Herculis|journal=The Astrophysical Journal|volume=654|issue=1|pages=625–632|date=2007|doi=10.1086/509110|arxiv = astro-ph/0609117 |s2cid=14707902 }}

{{citation|arxiv=2105.11583|year=2021|title=The California Legacy Survey. I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades|doi=10.3847/1538-4365/abe23c |last1=Rosenthal |first1=Lee J. |last2=Fulton |first2=Benjamin J. |last3=Hirsch |first3=Lea A. |last4=Isaacson |first4=Howard T. |last5=Howard |first5=Andrew W. |last6=Dedrick |first6=Cayla M. |last7=Sherstyuk |first7=Ilya A. |last8=Blunt |first8=Sarah C. |last9=Petigura |first9=Erik A. |last10=Knutson |first10=Heather A. |last11=Behmard |first11=Aida |last12=Chontos |first12=Ashley |last13=Crepp |first13=Justin R. |last14=Crossfield |first14=Ian J. M. |last15=Dalba |first15=Paul A. |last16=Fischer |first16=Debra A. |last17=Henry |first17=Gregory W. |last18=Kane |first18=Stephen R. |last19=Kosiarek |first19=Molly |last20=Marcy |first20=Geoffrey W. |last21=Rubenzahl |first21=Ryan A. |last22=Weiss |first22=Lauren M. |last23=Wright |first23=Jason T. |journal=The Astrophysical Journal Supplement Series |volume=255 |issue=1 |page=8 |bibcode=2021ApJS..255....8R |s2cid=235186973 |doi-access=free }}

{{cite journal | last1=Bardalez Gagliuffi | first1=Daniella C. | last2=Faherty | first2=Jacqueline K. | last3=Li | first3=Yiting | last4=Brandt | first4=Timothy D. | last5=Williams | first5=Lauryn | last6=Brandt | first6=G. Mirek | last7=Gelino | first7=Christopher R. | display-authors=1 | title=14 Her: A Likely Case of Planet–Planet Scattering | journal=The Astrophysical Journal Letters | date=1 December 2021 | volume=922 | issue=2 | at=L43 | arxiv=2111.06004 | bibcode=2021ApJ...922L..43B | bibcode-access=free | doi=10.3847/2041-8213/ac382c | 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 }}

{{cite journal |last1=Bardalez Gagliuffi |first1=Daniella |last2=Balmer |first2=William O. |display-authors=etal |date=June 2025 |title=JWST Coronagraphic Images of 14 Her c: a Cold Giant Planet in a Dynamically Hot, Multi-planet System |journal=The Astrophysical Journal Letters |volume= |issue= |pages= |doi= |arxiv=2506.09201}}

{{cite arXiv|eprint=2506.13580 |last1=Xiao |first1=Guang-Yao |last2=Feng |first2=Fabo |title=Updated Mutual Inclination Measurement for 14 Her b and c |date=2025 |class=astro-ph.EP }}

{{Cite journal |last=Naef |first=D. |last2=Mayor |first2=M. |last3=Beuzit |first3=J. L. |last4=Perrier |first4=C. |last5=Queloz |first5=D. |last6=Sivan |first6=J. P. |last7=Udry |first7=S. |date=January 2004 |title=The ELODIE survey for northern extra-solar planets. III. Three planetary candidates detected with ELODIE |url=https://ui.adsabs.harvard.edu/abs/2004A&A...414..351N/abstract |journal=Astronomy and Astrophysics |language=en |volume=414 |pages=351–359 |arxiv=astro-ph/0310261 |bibcode=2004A&A...414..351N |doi=10.1051/0004-6361:20034091 |issn=0004-6361}}

}}