Gliese 414 Ac
{{Short description|Frigid super-Neptune exoplanet orbiting GJ 414 A}}
{{Infobox planet
| caption = Artistical representation of a super-Neptune exoplanet.
| discoverer = Dedrick et al.
| period = {{val|749.83|4.35|3.63|ul=day}}
{{Val|2.054|ul=year}}
| mean_radius = {{val|8.4|3.6|2.5|ul=Earth radius}}
({{val|0.749|0.321|0.223|ul=Jupiter radius}})
| name = Gliese 414 A c
| image = 230px
| discovered = 2020
| discovery_method = Radial velocity
| discovery_ref = {{Cite web |last=Martin |first=Pierre-Yves |date=2020 |title=Planet GJ 414 A b |url=https://exoplanet.eu/catalog/gj_414_a_b--7489/ |access-date=2023-12-14 |work=Extrasolar Planets Encyclopaedia |language=en |archive-date=2023-12-14 |archive-url=https://web.archive.org/web/20231214131021/https://exoplanet.eu/catalog/gj_414_a_b--7489/ |url-status=live }}
| alt_names = HD 97101 Ac, HIP 54646 c
| semimajor = {{val|1.4|0.055|0.06|ul=AU}}
| eccentricity = {{val|0.093|0.1|0.064}}
| arg_peri = {{val|74|74|200|ul=°}}
| star = Gliese 414 A
| mass = {{val|53.83|9.18|8.58|ul=Earth mass}}
({{val|0.169|0.029|0.027|ul=Jupiter mass}})
| single_temperature = {{val|123.3|13.2|ul=K}} ({{convert|-149.7|C|F}}){{Efn|Assuming a bond albedo of 0.343, the same as Saturn.|name=Bond albedo|group=}}
}}
Gliese 414 Ac, or GJ 414 Ac, is an exoplanet orbiting Gliese 414 A, a K-type main-sequence star located 39 light-years from Earth, in the constellation Ursa Major.{{Cite web |title=Gliese 414 {{!}} NASA Exoplanet Archive |url=https://exoplanetarchive.ipac.caltech.edu/overview/GJ%20414 |access-date=2023-12-14 |website=exoplanetarchive.ipac.caltech.edu |archive-date=2023-12-09 |archive-url=https://web.archive.org/web/20231209091347/https://exoplanetarchive.ipac.caltech.edu/overview/GJ%20414 |url-status=live }}{{Efn|name=Constellation 1|group=note}} It is classified as a super-Neptune exoplanet, being at least 54 times more massive than the Earth and about 8.5 times larger.{{Cite journal |last1=Dedrick |first1=Cayla M. |last2=Fulton |first2=Benjamin J. |last3=Knutson |first3=Heather A. |last4=Howard |first4=Andrew W. |last5=Beatty |first5=Thomas G. |last6=Cargile |first6=Phillip A. |last7=Gaudi |first7=B. Scott |last8=Hirsch |first8=Lea A. |last9=Kuhn |first9=Rudolf B. |last10=Lund |first10=Michael B. |last11=James |first11=David J. |last12=Kosiarek |first12=Molly R. |last13=Pepper |first13=Joshua |last14=Petigura |first14=Erik A. |last15=Rodriguez |first15=Joseph E. |date=2021-02-01 |title=Two Planets Straddling the Habitable Zone of The Nearby K Dwarf Gl 414A |journal=The Astronomical Journal |volume=161 |issue=2 |pages=86 |doi=10.3847/1538-3881/abd0ef |arxiv=2009.06503 |bibcode=2021AJ....161...86D |issn=0004-6256 |doi-access=free }} Gliese 414 Ac orbits its parent star at a distance of 1.4 astronomical units and completes one revolution around it every 2 years and 20 days. It is one of the two planets orbiting Gliese 414 A, the other is Gliese 414 Ab, a sub-Neptune.
Characteristics
Gliese 414 Ac is classified as a super-Neptune (or sub-Saturn), a type of exoplanets that are more massive than Neptune, but less massive than Saturn, having masses between 20 and 80{{nbsp}}{{Earth mass|sym=y|link=y}}.{{Cite web |last=Staff |first=Space.com |date=2009-03-14 |title=Super-Neptune Planet Found |url=https://www.space.com/6338-super-neptune-planet.html |access-date=2024-01-31 |website=Space.com |language=en |archive-date=2024-01-31 |archive-url=https://web.archive.org/web/20240131212810/https://www.space.com/6338-super-neptune-planet.html |url-status=live }} The planet has a minimum mass of 54{{nbsp}}{{Earth mass|sym=y}} and a radius of 8.4{{nbsp}}{{Earth radius|link=y}}, both values between Neptune and Saturn.{{Efn|Neptune has a mass of 17.15 {{Earth mass|sym=y}} and a radius of 3.88 {{Earth radius}}, while Saturn has a mass of 95.2 {{Earth mass|sym=y}} and a radius of 9.45 {{Earth radius}}.{{Cite web |title=Planetary Physical Parameters |url=https://ssd.jpl.nasa.gov/planets/phys_par.html |access-date=January 31, 2024 |website=ssd.jpl.nasa.gov |archive-date=October 4, 2022 |archive-url=https://web.archive.org/web/20221004115344/https://ssd.jpl.nasa.gov/planets/phys_par.html |url-status=live }} |name=Neptune and Saturn}}
It completes one orbit around its star approximately every two years, and is located at a distance of {{convert|1.4|AU|km|lk=in}} from it, too far to be located in the habitable zone of its star, which extends up to 0.7 AU. Due to the great separation from its star, the planet is frigid, having an equilibrium temperature of around -150 °C, comparable to Saturn, which has a temperature of -140 °C.{{Cite web |title=Solar System Temperatures - NASA Science |url=https://science.nasa.gov/resource/solar-system-temperatures/ |access-date=2023-12-14 |website=science.nasa.gov |language=en |archive-date=2023-10-01 |archive-url=https://archive.today/20231001035325/https://science.nasa.gov/resource/solar-system-temperatures/ |url-status=live }} Gliese 414 Ac is as a potential candidate for future direct imaging missions.
Discovery
Gliese 414 Ac was discovered in 2020 by analyzing radial velocity data from Keck's HIRES instrument and the Automated Planet Finder at Lick Observatory, as well as photometric data from KELT.{{Cite web |title=Open Exoplanet Catalogue - Gliese 414 Ab |url=https://www.openexoplanetcatalogue.com/planet/GJ%20414%20A%20b/ |access-date=2023-12-14 |website=www.openexoplanetcatalogue.com |archive-date=2023-12-14 |archive-url=https://web.archive.org/web/20231214114557/https://www.openexoplanetcatalogue.com/planet/GJ%20414%20A%20b/ |url-status=live }}
Host star
{{main|Gliese 414}}
Gliese 414 Ac orbits Gliese 414 A, an orange dwarf (spectral type K7V{{Cite web |title=HD 97101 |url=https://simbad.cds.unistra.fr/mobile/object.html?object_name=HD%2097101 |access-date=January 31, 2024 |website=SIMBAD}}) that is smaller and cooler than the Sun. The star has a radius of 0.68{{nbsp}}{{Solar radius|link=y}}, a mass of 0.65{{Nbsp}}{{Solar mass|link=y}} and a temperature of {{convert|4120|K|C|lk=in}}. It is a binary star, having an orbital companion called Gliese 414 B, a red dwarf star that is at a projected distance of 408 astronomical units from it.{{Cite web |last=Anderson |first=Natali |date=2020-09-21 |title=Astronomers Find Two Massive Exoplanets in Nearby Binary System {{!}} Astronomy {{!}} Sci-News.com |url=https://www.sci.news/astronomy/two-massive-exoplanets-nearby-binary-system-08870.html |access-date=2024-01-13 |website=Sci.News: Breaking Science News |language=en-US |archive-date=2024-01-13 |archive-url=https://web.archive.org/web/20240113140329/https://www.sci.news/astronomy/two-massive-exoplanets-nearby-binary-system-08870.html |url-status=live }}
The stellar system is located about 39 light-years from the Earth, in the constellation Ursa Major.{{Efn|Obtained with a right ascension of {{RA|11|11|5.17}} and a declination of {{DEC|+30|26|45.7}} on this [https://djm.cc/constellation.html website].|name=Constellation 1|group=note}} Both stars are too faint and can't be seen with the naked eye.{{Cite web |title=Gliese 414 |url=https://www.stellarcatalog.com/stars/gliese-414-a |access-date=January 31, 2024 |website=Stellar Catalog |archive-date=December 13, 2023 |archive-url=https://web.archive.org/web/20231213211446/https://www.stellarcatalog.com/stars/gliese-414-a |url-status=live }}
There is another planet orbiting Gliese 414 A. Named Gliese 414 Ab, it is a sub-Neptune that is located {{Convert|0.23|AU|km|lk=in|abbr=on}} from it (6 times closer than Gliese 414 Ac). The planet has an eccentric orbit and its distance from its star varies between 0.13 and 0.34 AU, which means that it is occasionally located in the optimistic habitable zone. The planet has a radius of 2.95{{nbsp}}{{Earth radius|link=y}} and a minimum mass of 7.6{{nbsp}}{{Earth mass|sym=y|link=y}}.
See also
Notes and references
{{2020 in space}}
{{Ursa Major}}
Category:Exoplanets discovered in 2020
Category:Exoplanets detected by radial velocity