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Rare exoplanet 37 EP

TOI-1291 b

RA 245.8180° · Dec 62.9251° · exoplanet

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Score breakdown

· 6 badges
37 pts · Rare
Rare 50 pts → Epic
  • Lava world +14
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Neptune-like +4
  • Blasted by starlight +4
  • Found by TESS +4
Total score 37

13 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Neptune-like · +4
  • Lava world · +14
  • 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 11.5 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 May — that's when to go looking.

Properties

density gcc
0.831
diameter km
71922.8221
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2026
dist ly
1396.3489
eq temp k
1649
host star teff
6139.95
inclination
88.3839
insolation
1230.42
mag
11.516
mass earth
27.1
name
TOI-1291 b
orbital period days
7.162
radius earth
5.6383
sys num planets
1
sys num stars
1

About TOI-1291 b

TOI-1291 b is a rare exoplanet. It lies about 1,396.3 light-years from Earth, shines at apparent magnitude 11.52, has an equilibrium temperature near 1,649 K and spans roughly 5.64 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 11.52, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-1291 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-1291 b is a rare exoplanet

TOI-1291 b scores 37 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Neptune-like, Lava 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.