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Common exoplanet 17 EP

TOI-198 b

RA 2.2715° · Dec -27.1217° · exoplanet

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Score breakdown

· 3 badges
17 pts · Common
Common 22 pts → Uncommon
  • Super-Earth +8
  • Confirmed exoplanet +5
  • Found by TESS +4
Total score 17

5 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Super-Earth · +8
  • Found by TESS · +4

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.
  • What it is made of. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 11.7 you'll want a small backyard telescope.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around September — 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. ≈ 1.4 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
6.89
diameter km
17348.432
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2023
dist ly
77.3844
eccentricity
0.15
eq temp k
456
host star teff
3801
inclination
89.63
insolation
7.2
mag
11.688
mass earth
3.17
name
TOI-198 b
orbital period days
10.2152
radius earth
1.36
semi major au
0.0675
spect
M0 V
sys num planets
1
sys num stars
1

About TOI-198 b

TOI-198 b is a common exoplanet. It lies about 77.4 light-years from Earth, shines at apparent magnitude 11.69, has spectral type M0 V and has an equilibrium temperature near 456 K.

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 11.69, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-198 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-198 b is a common exoplanet

TOI-198 b scores 17 points on Spacedle's rarity scale, which places it in the common tier. Another 5 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Super-Earth 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.