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Common exoplanet 15 EP

K2-161 b

RA 183.7938° · Dec -3.4957° · exoplanet

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Score breakdown

· 3 badges
15 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 15

7 more points to reach Uncommon.

Badges

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

Trivia

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

  • 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. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

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 12.7 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around March — 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
0.747
diameter km
78032.3834
discovery facility
K2
discovery method
Transit
discovery year
2018
dist ly
2988.6294
host star teff
4972
inclination
87.2509
mag
12.718
mass earth
31.1
name
K2-161 b
orbital period days
9.2832
radius earth
6.1172
sys num planets
1
sys num stars
1

Nearby objects

About K2-161 b

K2-161 b is a common exoplanet. It lies about 2,988.6 light-years from Earth, shines at apparent magnitude 12.72, spans roughly 6.12 Earth radii and weighs about 31.1 Earth masses.

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 12.72, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-161 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 K2-161 b is a common exoplanet

K2-161 b scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Distant (over 1,000 light-years) and Gas giant — 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.