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Uncommon exoplanet 32 EP

TOI-2120 b

RA 23.5073° · Dec 65.5140° · exoplanet

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Score breakdown

· 5 badges
32 pts · Uncommon
Uncommon 34 pts → Rare
  • Tidally locked +10
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
  • Sub-Neptune +5
  • Found by TESS +4
Total score 32

2 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Tidally locked · +10
  • Found by TESS · +4
  • Orbits a red dwarf · +8

Trivia

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.

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 15.6 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • 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 October — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 1.8 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 163.9 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

diameter km
27068.6564
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2024
dist ly
104.9423
eccentricity
0.32
eq temp k
384
host star teff
3131
inclination
88.67
insolation
3.61
mag
15.648
mass earth
6.8
name
TOI-2120 b
orbital period days
5.7998
radius earth
2.122
semi major au
0.0377
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-2120 b

TOI-2120 b is an uncommon exoplanet. It lies about 104.9 light-years from Earth, shines at apparent magnitude 15.65, has an equilibrium temperature near 384 K and spans roughly 2.12 Earth radii.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 15.65, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, TOI-2120 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-2120 b is an uncommon exoplanet

TOI-2120 b scores 32 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 2 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Sub-Neptune, Tidally locked, Found by TESS and Orbits a red dwarf — 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.