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Epic exoplanet 53 EP

TOI-2578 b

RA 68.0521° · Dec 52.2527° · exoplanet

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Score breakdown

· 7 badges
53 pts · Epic
Epic 78 pts → Anomaly
  • Lava world +14
  • Puffy low-density world +12
  • Tidally locked +10
  • Confirmed exoplanet +5
  • Gas giant +4
  • Blasted by starlight +4
  • Found by TESS +4
Total score 53

25 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Lava world · +14
  • Tidally locked · +10
  • Puffy low-density world · +12
  • Blasted by starlight · +4
  • Found by TESS · +4

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 11.4 you'll want a small backyard telescope.
  • 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.

Properties

density gcc
0.121
diameter km
250793.9353
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2026
dist ly
931.2732
eccentricity
0.098
eq temp k
1778
host star teff
6333
inclination
81.32
insolation
1667
mag
11.353
mass earth
167.1777
name
TOI-2578 b
orbital period days
3.458
radius earth
19.6606
semi major au
0.0495
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-2578 b

TOI-2578 b is an epic exoplanet. It lies about 931.3 light-years from Earth, shines at apparent magnitude 11.35, has an equilibrium temperature near 1,778 K and spans roughly 19.66 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 11.35, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-2578 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 TOI-2578 b is an epic exoplanet

TOI-2578 b scores 53 points on Spacedle's rarity scale, which places it in the epic tier. Another 25 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Gas giant, Lava world, Tidally locked, Puffy low-density world, Blasted by starlight and Found by TESS — 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.