← Back to dex
Epic exoplanet 77 EP

55 Cnc f

RA 133.1468° · Dec 28.3298° · exoplanet

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 6 badges
77 pts · Epic
Epic 78 pts → Anomaly
  • In the habitable zone +30
  • Richly packed system +14
  • Its star is visible to the naked eye +12
  • Two suns in its sky +12
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 77

1 more point to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Gas giant · +4
  • Richly packed system · +14
  • Its star is visible to the naked eye · +12
  • Two suns in its sky · +12

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

What it actually is

  • What it is made of. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.
  • What the zone means. The habitable zone is only about temperature: it is the band where liquid water could survive on a surface. It is a promising address, not evidence of anything living.
  • Crowded system. One of at least 7 planets orbiting its star.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 6 you can see it with your own eyes from a dark site.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.

Properties

density gcc
0.563
diameter km
96819.558
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2007
dist ly
41.0484
eccentricity
0.063
eq temp k
277.07
habitable zone
yes
host star teff
5198
inclination
89.73
insolation
0.9879
mag
5.9508
mass earth
44.812
multi star system
yes
name
55 Cnc f
orbital period days
260.58
radius earth
7.59
semi major au
0.802
spect
G8 V
sys num planets
7
sys num stars
2

About 55 Cnc f

55 Cnc f is an epic exoplanet. It lies about 41 light-years from Earth, shines at apparent magnitude 5.95, has spectral type G8 V and has an equilibrium temperature near 277 K.

Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

How to see it

At apparent magnitude 5.95, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 55 Cnc f is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why 55 Cnc f is an epic exoplanet

55 Cnc f scores 77 points on Spacedle's rarity scale, which places it in the epic tier. Another 1 point would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, In the habitable zone, Gas giant, Richly packed system, Its star is visible to the naked eye and Two suns in its sky — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.