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Rare exoplanet 41 EP

TOI-2154 b

RA 71.0281° · Dec 84.3643° · exoplanet

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Score breakdown

· 6 badges
41 pts · Rare
Rare 50 pts → Epic
  • Lava world +14
  • Tidally locked +10
  • Confirmed exoplanet +5
  • Gas giant +4
  • Blasted by starlight +4
  • Found by TESS +4
Total score 41

9 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Lava world · +14
  • Tidally locked · +10
  • 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 11.1 you'll want a small backyard telescope.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around December — that's when to go looking.

Properties

density gcc
0.37
diameter km
207755.7515
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2023
dist ly
966.9221
eccentricity
0.117
eq temp k
1580
host star teff
6280
inclination
83.37
insolation
1005.8946
mag
11.068
mass earth
292.4021
name
TOI-2154 b
orbital period days
3.8241
radius earth
16.2866
semi major au
0.0513
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-2154 b

TOI-2154 b is a rare exoplanet. It lies about 966.9 light-years from Earth, shines at apparent magnitude 11.07, has an equilibrium temperature near 1,580 K and spans roughly 16.29 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 11.07, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-2154 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-2154 b is a rare exoplanet

TOI-2154 b scores 41 points on Spacedle's rarity scale, which places it in the rare tier. Another 9 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Lava world, Tidally locked, 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.