55 Cancri f

55 Cancri f is an extrasolar planet orbiting the component 55 Cancri A of the binary system 55 Cancri. He is the fourth planet of the system and was discovered last. Due to its high mass, it is likely to be a gas planet.

Discovery

The detection of 55 Cancri f is based, as in the majority of all exoplanets found so far, and all other of the 55 Cancri system on measurements of the radial velocity of the central star. Jack Wisdom suspected after analysis of the radial velocity curves, the existence of the planet already in 2005 and announced it in April at the meeting of the American Astronomical Society. The publication in a scientific journal followed half years later. The calculations with the adoption of this fifth planet with a web in the large gap between the three narrow planets e, b and c and the more far planet d allowed a total of stable planetary system with low eccentricities of all planets, as to conformity with the generally accepted theories planet formation is plausible.

Web properties

The planet orbits its star at a distance of about 0.781 astronomical units with an eccentricity of 0.2. Its orbit is hardly more than that of Venus. He completed all 260 days a round.

Physical Properties

55 Cancri f has a minimum mass of about 45.78 Earth masses and 0.144 Jupiter masses. So he's at least half as heavy as Saturn. About its radius, the chemical composition and the surface temperatures can currently only be speculated. Most likely it is a gas planet with no solid surface. Starting from the orbit and the luminosity of 55 Cancri A, he could be in the habitable zone, so that liquid water and theoretical forms of life on a potential moon appear possible.

Swell

• Debra A. Fischer, Geoffrey W. Marcy, R. Paul Butler, et al.: Five Planets Orbiting 55 Cancri. The Astrophysical Journal, 675 (2008), pp. 790-801. doi: 10.1086/525512, arXiv: 0712.3917