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Common exoplanet 18 EP

Kepler-39 b

RA 296.9603° · Dec 46.0343° · exoplanet

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Score breakdown

· 4 badges
18 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by Kepler +3
Total score 18

4 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Found by Kepler · +3

Trivia

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.

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 14.4 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around July — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

density gcc
13
diameter km
177311.18
discovery facility
Kepler
discovery method
Transit
discovery year
2011
dist ly
3448.8062
eccentricity
0.112
eq temp k
897
host star teff
6350
inclination
89.07
insolation
90.22
mag
14.355
mass earth
6388.1
name
Kepler-39 b
orbital period days
21.0872
radius earth
13.9
semi major au
0.164
spect
F7 V
sys num planets
1
sys num stars
1

About Kepler-39 b

Kepler-39 b is a common exoplanet. It lies about 3,448.8 light-years from Earth, shines at apparent magnitude 14.36, has spectral type F7 V and has an equilibrium temperature near 897 K.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 14.36, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Kepler-39 b 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 Kepler-39 b is a common exoplanet

Kepler-39 b scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant and Found by Kepler — 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.