About 55 Cnc d
55 Cnc d is an epic exoplanet. It lies about 41 light-years from Earth, has an equilibrium temperature near 105 K, spans roughly 13 Earth radii and weighs about 1,232.49 Earth masses.
A deep-frozen world far from its star's warmth.
Epic exoplanet 47 EP
55 Cnc d
RA 133.1468° · Dec 28.3298° · exoplanet
Score breakdown
· 6 badgesEpic 68 pts → Anomaly
- Richly packed system +14
- Long-period world +10
- Frozen world +8
- Multi-planet system +6
- Confirmed exoplanet +5
- Gas giant +4
Total score 47
21 more points to reach Anomaly.
Badges
- Confirmed exoplanet · +5
- Gas giant · +4
- Frozen world · +8
- Long-period world · +10
- Multi-planet system · +6
- Richly packed system · +14
Trivia
What makes it special
- Frozen world. A deep-frozen world far from its star's warmth.
- Packed system. Crammed into a system of five or more planets.
Could we get there?
- Verdict. Hopelessly far for any craft humanity can build today.
Getting there
- Aboard Voyager 1. ≈ 721.3 thousand years at Voyager 1's speed (17 km/s).
- Fastest probe ever. ≈ 64.1 thousand years even at the Parker Solar Probe's 192 km/s.
- At 10% light speed. ≈ 410 years in a starship at a tenth of light speed.
- Distance. 41 light-years from Earth.
Look-back time
- Look-back time. The light you'd see left around the year 1985.
Saying hello
- Say hello. A radio message and its reply would take 82.1 years round-trip.
Standing on it
- A year here. A full year lasts about 13.1 Earth years.
By the numbers
- Size. About 13× the width of Earth.
- Volume. About 2197 Earths could fit inside it.
- Mass. Roughly 1232× Earth's mass — about 3.9 Jupiters.
- Your weight. You'd weigh about 7.3× your Earth weight standing here.
- Temperature. A frigid -168°C — colder than dry ice.
How we found it
- Discovery. Found by Lick Observatory using the radial velocity method.
Cosmic context
- Crowded system. One of at least 7 planets orbiting its star.
Properties
- density gcc
- 3.08
- discovery facility
- Lick Observatory
- discovery method
- Radial Velocity
- dist ly
- 41.0484
- eccentricity
- 0.0913
- eq temp k
- 104.85
- insolation
- 0.0203
- mass earth
- 1232.493
- name
- 55 Cnc d
- orbital period days
- 4799
- radius earth
- 13
- sys num planets
- 7
How to see it
Like any astronomical target, 55 Cnc d 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 d is an epic exoplanet
55 Cnc d scores 47 points on Spacedle's rarity scale, which places it in the epic tier. Another 21 points would lift it into a rarer tier.
That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Frozen world, Long-period world, Multi-planet system and Richly packed system — 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.