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Epic exoplanet 67 EP

K2-3 d

RA 172.3354° · Dec -1.4551° · exoplanet

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Score breakdown

· 5 badges
67 pts · Epic
Epic 78 pts → Anomaly
  • In the habitable zone +30
  • Denser than iron +18
  • Super-Earth +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
Total score 67

11 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Super-Earth · +8
  • Denser than iron · +18
  • Multi-planet system · +6

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

  • Denser than iron. It is packed tighter than solid iron — whatever it is made of, it is not ordinary rock.

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.
  • 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 3 planets orbiting its star.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 12.2 it is far too faint for the eye: this one belongs to cameras and long exposures.

Properties

density gcc
17.5
diameter km
18598.5396
discovery facility
K2
discovery method
Transit
discovery year
2015
dist ly
143.7458
eccentricity
0.091
eq temp k
305.2
habitable zone
yes
host star teff
3844
inclination
89.82
insolation
1.44
mag
12.168
mass earth
2.2
name
K2-3 d
orbital period days
44.556
radius earth
1.458
semi major au
0.2014
spect
M V
sys num planets
3
sys num stars
1

About K2-3 d

K2-3 d is an epic exoplanet. It lies about 143.7 light-years from Earth, shines at apparent magnitude 12.17, has spectral type M V and has an equilibrium temperature near 305 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 12.17, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-3 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 K2-3 d is an epic exoplanet

K2-3 d scores 67 points on Spacedle's rarity scale, which places it in the epic tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, In the habitable zone, Super-Earth, Denser than iron and Multi-planet 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.