55 Cancri f
Periastron 0.730 AU (109,200,000 km) | | |
0.781 ± 0.007 AU (116,800,000 ± 1,000,000 km)[1] | ||
Eccentricity | 0.2 ± 0.2[1] | |
260.00 ± 1.1[1] d 0.7118 y | ||
2,450,080.9108 ± 1.1[1] | ||
181.1 ± 60[1] | ||
Semi-amplitude | 4.879 ± 0.6[1] | |
Star | 55 Cancri A | |
Physical characteristics | ||
Temperature | 200–300 K (−73–27 °C; −100–80 °F) | |
55 Cancri f (abbreviated 55 Cnc f), also designated Rho1 Cancri f and formally named Harriot /ˈhæriət/,[2] is an exoplanet approximately 41 light-years away from Earth in the constellation of Cancer (the Crab). 55 Cancri f is the fourth known planet (in order of distance) from the star 55 Cancri and the first planet to have been given the designation of "f".[3]
Name
In July 2014 the International Astronomical Union launched NameExoWorlds, a process for giving proper names to certain exoplanets and their host stars.[4] The process involved public nomination and voting for the new names.[5] In December 2015, the IAU announced the winning name was Harriot for this planet.[6] The winning name was submitted by the Royal Netherlands Association for Meteorology and Astronomy of the Netherlands. It honors the astronomer Thomas Harriot.[7]
Discovery
The initial presentation of this planet occurred at a meeting of the American Astronomical Society in April 2005,[8] however it was another two and a half years before the planet was to be published in a peer-reviewed journal.[1] It is the first known planet outside the Solar System to spend its entire orbit within what astronomers call the "habitable zone".[9] Furthermore, its discovery made 55 Cancri the first star other than the Sun known to have at least five planets.
Orbit and mass
55 Cancri f is located about 0.781
Astrometric observations made with the Hubble Space Telescope suggest that the outer planet 55 Cancri d is inclined at 53° with respect to the plane of the sky.[11] The inner planets b and e are inclined at 85°. The inclination of f is unknown.
Characteristics
Since the planet was detected indirectly through observations of its star, properties such as its radius, composition and temperature are unknown. With a mass half that of Saturn,[10] 55 Cancri f is likely to be a gas giant with no solid surface. It orbits in the so-called "habitable zone," which means that liquid water and life could exist on the surface of a possible moon or moons.[9]
It is not known if the composition and appearance is more like that of Saturn or Neptune.[3]
See also
- Appearance of extrasolar planets
- Cancer (Chinese astronomy)
- Lists of exoplanets
- Planetary system
References
- ^ S2CID 17083836.
- ^ "Mathematics Pronunciation Guide". Archived from the original on 4 September 2019. Retrieved 27 April 2019.
- ^ a b Shige Abe (12 November 2007). "Researchers Identify First Five-Planet Extrasolar System". NASA Astrobiology. Archived from the original on 16 September 2008. Retrieved 17 September 2008.
- ^ NameExoWorlds: An IAU Worldwide Contest to Name Exoplanets and their Host Stars. IAU.org. 9 July 2014
- ^ "NameExoWorlds The Process". Archived from the original on 15 August 2015. Retrieved 5 September 2015.
- ^ Final Results of NameExoWorlds Public Vote Released, International Astronomical Union, 15 December 2015.
- ^ "NameExoWorlds The Approved Names". Archived from the original on 1 February 2018. Retrieved 27 December 2015.
- ^ J. Wisdom (11 April 2005). "A Neptune-sized Planet in the rho1 Cancri System". DDA 36th Meeting, 10–14 April 2005—Session 5 Posters. The American Astronomical Society. Archived from the original on 16 December 2006. Retrieved 17 September 2008.
- ^ a b Ian Sample, science correspondent (7 November 2007). "Could this be Earth's near twin? Introducing planet 55 Cancri f". The Guardian. London. Archived from the original on 2 October 2008. Retrieved 17 October 2008.
- ^ a b c Jean Schneider (2011). "Notes for Planet 55 Cnc f". Extrasolar Planets Encyclopaedia. Retrieved 8 October 2011.
- doi:10.1086/318927.
External links
- Ward Glen (8 November 2007). "Astronomers Find Fifth Planet Around 55 Cancri". The Starry Mirror. Archived from the original on 10 November 2007. Retrieved 17 September 2008.