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Epic exoplanet 63 EP

TOI-1238 b

RA 201.3823° · Dec 68.8361° · exoplanet

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Score breakdown

· 6 badges
63 pts · Epic
Epic 78 pts → Anomaly
  • Denser than iron +18
  • Earth-sized +16
  • Ultra-short period +14
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Found by TESS +4
Total score 63

15 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Earth-sized · +16
  • Ultra-short period · +14
  • Denser than iron · +18
  • Multi-planet system · +6
  • Found by TESS · +4

Trivia

What makes it special

  • Earth-sized. Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

Hard to believe

  • Denser than iron. It is packed tighter than solid iron — whatever it is made of, it is not ordinary rock.
  • A year in a day. Its entire year is over in 18.4 hours. Birthdays here would come round faster than meals.

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. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.
  • Crowded system. One of at least 2 planets orbiting its star.

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 12.8 it is far too faint for the eye: this one belongs to cameras and long exposures.

Properties

density gcc
11.7
diameter km
15435.002
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2022
dist ly
230.6396
eccentricity
0.25
eq temp k
1133
host star teff
4089
inclination
86.51
insolation
442
mag
12.796
mass earth
3.76
name
TOI-1238 b
orbital period days
0.7646
radius earth
1.21
semi major au
0.0139
spect
K7/M0
sys num planets
2
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-1238 b

TOI-1238 b is an epic exoplanet. It lies about 230.6 light-years from Earth, shines at apparent magnitude 12.8, has spectral type K7/M0 and has an equilibrium temperature near 1,133 K.

Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

How to see it

At apparent magnitude 12.8, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, TOI-1238 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-1238 b is an epic exoplanet

TOI-1238 b scores 63 points on Spacedle's rarity scale, which places it in the epic tier. Another 15 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Earth-sized, Ultra-short period, Denser than iron, Multi-planet system 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.