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Epic exoplanet 51 EP

WASP-102 b

RA 336.4643° · Dec 15.8566° · exoplanet

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Score breakdown

· 7 badges
51 pts · Epic
Epic 78 pts → Anomaly
  • Lava world +14
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Blasted by starlight +4
Total score 51

27 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Lava world · +14
  • Tidally locked · +10
  • Blasted by starlight · +4
  • Orbits a Sun-like star · +8

Trivia

What makes it special

  • Lava world. Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

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.
  • 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 August — that's when to go looking.

Properties

density gcc
0.32
diameter km
190168.7195
discovery facility
SuperWASP
discovery method
Transit
discovery year
2025
dist ly
1747.1818
eccentricity
0
eq temp k
1671
host star teff
5990
inclination
89.06
insolation
1293
mag
12.667
mass earth
197.6893
name
WASP-102 b
orbital period days
2.7098
radius earth
14.9079
semi major au
0.041
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About WASP-102 b

WASP-102 b is an epic exoplanet. It lies about 1,747.2 light-years from Earth, shines at apparent magnitude 12.67, has an equilibrium temperature near 1,671 K and spans roughly 14.91 Earth radii.

Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

How to see it

At apparent magnitude 12.67, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, WASP-102 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 WASP-102 b is an epic exoplanet

WASP-102 b scores 51 points on Spacedle's rarity scale, which places it in the epic tier. Another 27 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant, Lava world, Tidally locked, Blasted by starlight 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.