Star system, 41 light-years
55 Cancri and its five planets
55 Cnc f is an exoplanet about 7.59 times Earth's width (a size estimated from its mass), about 0.7 times Jupiter's, 41 light-years away, orbiting in its star's computed habitable zone.
55 Cancri is a star of spectral type G8 V, 41 light-years from us, with five known planets. This page takes them one at a time.
Drawn at the system's own scale, every orbit from the Archive's numbers.
What is measured, what is computed, what is imagined.
measured The period, and where the table says so the width and the mass, by the method named in each section.
computed Anything marked computed: the size of an orbit where Kepler's third law corrects the table, the temperature of a bare ball at that distance, the starlight received, and the habitable zone.
imagined The picture is an artist's impression. Nobody has seen the surface of a planet of another star: its colour, clouds and land are not known, and the share picture says so in its corner.
The planets
55 Cnc e
55 Cnc e is an exoplanet 1.875 times Earth's width, 41 light-years away, orbiting closer to its star than the habitable zone we compute for it.
- Width
- 1.875 × Earth's measured
- Mass
- 7.99 times Earth's measured
- One year
- 0.73655 days measured
- Distance from its star
- 0.01604 au computed from the period and the star's mass
- Temperature of a bare ball there
- 1,795 K computed, not measured
- Starlight, against Earth's
- 2470 × computed
It was found by the back-and-forth wobble its pull puts into its star's motion, seen as a shift in the colour of the star's light in 2004. Its orbit is closer to its star than the habitable zone computed for it. The Archive's own distance for it is 0.01544 au; the three papers behind its period, its star's mass and that distance do not agree with Kepler's third law, so the page uses the one the period and the star's mass give.
See 55 Cnc e in 3D · The picture is an artist's impression.
55 Cnc b
55 Cnc b is an exoplanet about 13.9 times Earth's width (a size estimated from its mass), about 1.2 times Jupiter's, 41 light-years away, orbiting closer to its star than the habitable zone we compute for it.
- Width
- 13.9 × Earth's estimated
- Mass
- 263.978 times Earth's measured
- One year
- 14.6516 days measured
- Distance from its star
- 0.118 au from the Archive
- Temperature of a bare ball there
- 662 K computed, not measured
- Starlight, against Earth's
- 45.6 × computed
It was found by the back-and-forth wobble its pull puts into its star's motion, seen as a shift in the colour of the star's light in 1996. Its orbit is closer to its star than the habitable zone computed for it.
See 55 Cnc b in 3D · The picture is an artist's impression.
55 Cnc c
55 Cnc c is an exoplanet about 8.51 times Earth's width (a size estimated from its mass), about 0.8 times Jupiter's, 41 light-years away, orbiting closer to its star than the habitable zone we compute for it.
- Width
- 8.51 × Earth's estimated
- Mass
- 54.474 times Earth's measured
- One year
- 44.3936 days measured
- Distance from its star
- 0.247 au from the Archive
- Temperature of a bare ball there
- 457 K computed, not measured
- Starlight, against Earth's
- 10.4 × computed
It was found by the back-and-forth wobble its pull puts into its star's motion, seen as a shift in the colour of the star's light in 2004. Its orbit is closer to its star than the habitable zone computed for it.
See 55 Cnc c in 3D · The picture is an artist's impression.
55 Cnc f
55 Cnc f is an exoplanet about 7.59 times Earth's width (a size estimated from its mass), about 0.7 times Jupiter's, 41 light-years away, orbiting in its star's computed habitable zone.
- Width
- 7.59 × Earth's estimated
- Mass
- 44.812 times Earth's measured
- One year
- 260.58 days measured
- Distance from its star
- 0.802 au from the Archive
- Temperature of a bare ball there
- 254 K computed, not measured
- Starlight, against Earth's
- 0.988 × computed
It was found by the back-and-forth wobble its pull puts into its star's motion, seen as a shift in the colour of the star's light in 2007. Its orbit lies inside the conservative habitable zone computed for its star (liquid water on a rocky world's surface would be possible there, which says nothing about whether any is).
See 55 Cnc f in 3D · The picture is an artist's impression.
55 Cnc d
55 Cnc d is an exoplanet about 13 times Earth's width (a size estimated from its mass), about 1.2 times Jupiter's, 41 light-years away, orbiting farther from its star than the habitable zone we compute for it.
- Width
- 13 × Earth's estimated
- Mass
- 1,232 times Earth's measured
- One year
- 4,799 days measured
- Distance from its star
- 5.6 au from the Archive
- Temperature of a bare ball there
- 96 K computed, not measured
- Starlight, against Earth's
- 0.0203 × computed
It was found by the back-and-forth wobble its pull puts into its star's motion, seen as a shift in the colour of the star's light in 2002. Its orbit is farther from its star than the habitable zone computed for it.
See 55 Cnc d in 3D · The picture is an artist's impression.
The star
- Surface temperature
- 5,198 K
- Width
- 0.98 × the Sun's
- Mass
- 1.015 × the Sun's
- Spectral type
- G8 V
- Distance
- 41 light-years
- Habitable zone, computed
- 0.7831 to 1.406 au from the star
- Stars in the system
- 2