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Trash exoplanet 9 EP

HD 103197 b

RA 178.2202° · Dec -50.2928° · exoplanet

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Score breakdown

· 2 badges
9 pts · Trash
Trash 15 pts → Common
  • Confirmed exoplanet +5
  • Neptune-like +4
Total score 9

6 more points to reach Common.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +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

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

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 9.4 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 March — that's when to go looking.

Could we get there?

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

Properties

density gcc
0.793
diameter km
74368.646
discovery facility
La Silla Observatory
discovery method
Radial Velocity
discovery year
2011
dist ly
186.3861
eccentricity
0
eq temp k
474.97
host star teff
5250
insolation
7.52
mag
9.4
mass earth
28.6047
name
HD 103197 b
orbital period days
47.84
radius earth
5.83
semi major au
0.25
spect
K1 V(P)
sys num planets
1
sys num stars
1

About HD 103197 b

HD 103197 b is a trash exoplanet. It lies about 186.4 light-years from Earth, shines at apparent magnitude 9.4, has spectral type K1 V(P) and has an equilibrium temperature near 475 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 9.4, a small backyard telescope will bring it into view.

Like any astronomical target, HD 103197 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 HD 103197 b is a trash exoplanet

HD 103197 b scores 9 points on Spacedle's rarity scale, which places it in the trash tier. Another 6 points would lift it into a rarer tier.

That score comes from 2 science badges — Confirmed exoplanet and Neptune-like — 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.