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Epic exoplanet 60 EP

55 Cnc B c

RA 133.1679° · Dec 28.3153° · exoplanet

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Score breakdown

· 5 badges
60 pts · Epic
Epic 68 pts → Anomaly
  • In the habitable zone +30
  • Richly packed system +14
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 60

8 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Sub-Neptune · +5
  • Multi-planet system · +6
  • Richly packed system · +14

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist.
  • 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. ≈ 715.1 thousand years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 63.5 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 407 years in a starship at a tenth of light speed.
  • Distance. 40.7 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 81.4 years round-trip.

Standing on it

  • A year here. A full year lasts just 33.7 Earth days.

By the numbers

  • Size. About 2.2× the width of Earth.
  • Volume. About 10.1 Earths could fit inside it.
  • Mass. About 5.3× the mass of Earth.
  • Your weight. You'd weigh about 1.1× your Earth weight standing here.
  • Temperature. A frigid -43°C — colder than dry ice.

How we found it

  • Discovery. Found by Mauna Kea Observatory using the radial velocity method.

Cosmic context

  • Crowded system. One of at least 7 planets orbiting its star.

Properties

density gcc
2.89
discovery facility
Mauna Kea Observatory
discovery method
Radial Velocity
dist ly
40.6955
eccentricity
0
eq temp k
230.04
habitable zone
yes
insolation
0.4613
mass earth
5.3
name
55 Cnc B c
orbital period days
33.747
radius earth
2.16
sys num planets
7

About 55 Cnc B c

55 Cnc B c is an epic exoplanet. It lies about 40.7 light-years from Earth, has an equilibrium temperature near 230 K, spans roughly 2.16 Earth radii and weighs about 5.3 Earth masses.

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

How to see it

Like any astronomical target, 55 Cnc B c 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 B c is an epic exoplanet

55 Cnc B c scores 60 points on Spacedle's rarity scale, which places it in the epic tier. Another 8 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, In the habitable zone, Sub-Neptune, 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.