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Uncommon exoplanet 33 EP

K2-87 b

RA 66.2364° · Dec 18.8274° · exoplanet

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Score breakdown

· 5 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 33

1 more point to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Tidally locked · +10
  • Orbits a Sun-like star · +8

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 14.1 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 November — 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
0.562
diameter km
96947.12
discovery facility
K2
discovery method
Transit
discovery year
2016
dist ly
1602.2153
eq temp k
979
host star teff
5747
inclination
87.74
insolation
85
mag
14.136
mass earth
44.9
name
K2-87 b
orbital period days
9.7266
radius earth
7.6
semi major au
0.094
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About K2-87 b

K2-87 b is an uncommon exoplanet. It lies about 1,602.2 light-years from Earth, shines at apparent magnitude 14.14, has an equilibrium temperature near 979 K and spans roughly 7.6 Earth radii.

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

Like any astronomical target, K2-87 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 K2-87 b is an uncommon exoplanet

K2-87 b scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant, Tidally locked and Orbits a Sun-like star — 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.