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Rare exoplanet 45 EP

TOI-1820 b

RA 187.6867° · Dec 27.4520° · exoplanet

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Score breakdown

· 6 badges
45 pts · Rare
Rare 50 pts → Epic
  • Lava world +14
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by TESS +4
Total score 45

5 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Lava world · +14
  • Tidally locked · +10
  • Found by TESS · +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.

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. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.

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 10.9 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 March — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Properties

density gcc
2
diameter km
163001.7596
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2022
dist ly
810.5107
eccentricity
0.043
eq temp k
1375
host star teff
5734
inclination
84.4
insolation
292.245
mag
10.899
mass earth
731.0053
name
TOI-1820 b
orbital period days
4.8607
radius earth
12.7782
semi major au
0.061
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-1820 b

TOI-1820 b is a rare exoplanet. It lies about 810.5 light-years from Earth, shines at apparent magnitude 10.9, has an equilibrium temperature near 1,375 K and spans roughly 12.78 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 10.9, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-1820 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-1820 b is a rare exoplanet

TOI-1820 b scores 45 points on Spacedle's rarity scale, which places it in the rare tier. Another 5 points would lift it into a rarer tier.

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