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Common exoplanet 19 EP

TOI-199 b

RA 80.1059° · Dec -59.8954° · exoplanet

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Score breakdown

· 4 badges
19 pts · Common
Common 22 pts → Uncommon
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by TESS +4
Total score 19

3 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6
  • Found by TESS · +4

Trivia

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

  • 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.
  • 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 10.7 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 December — that's when to go looking.

Could we get there?

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

Properties

density gcc
0.397
diameter km
115817.0397
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2023
dist ly
333.5597
eccentricity
0.09
eq temp k
325
host star teff
5255
inclination
90
insolation
8.5419
mag
10.701
mass earth
54.0308
name
TOI-199 b
orbital period days
104.854
radius earth
9.0793
semi major au
0.4254
spect
G9 V
sys num planets
2
sys num stars
1

About TOI-199 b

TOI-199 b is a common exoplanet. It lies about 333.6 light-years from Earth, shines at apparent magnitude 10.7, has spectral type G9 V and has an equilibrium temperature near 325 K.

Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

How to see it

At apparent magnitude 10.7, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-199 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-199 b is a common exoplanet

TOI-199 b scores 19 points on Spacedle's rarity scale, which places it in the common tier. Another 3 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, 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.