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Uncommon exoplanet 24 EP

HD 20003 b

RA 46.9090° · Dec -72.3219° · exoplanet

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Score breakdown

· 4 badges
24 pts · Uncommon
Uncommon 34 pts → Rare
  • Orbits a Sun-like star +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 24

10 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Multi-planet system · +6
  • Orbits a Sun-like star · +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.
  • 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 8.4 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • Best time of year. It stands highest in the middle of the night around November — that's when to go looking.

Could we get there?

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

Properties

density gcc
1.59
diameter km
43753.766
discovery facility
La Silla Observatory
discovery method
Radial Velocity
discovery year
2019
dist ly
136.4363
eccentricity
0.36
eq temp k
814.93
host star teff
5494
insolation
75.8952
mag
8.39
mass earth
11.66
name
HD 20003 b
orbital period days
11.8482
radius earth
3.43
semi major au
0.0974
spect
G8 V
sys num planets
2
sys num stars
1

About HD 20003 b

HD 20003 b is an uncommon exoplanet. It lies about 136.4 light-years from Earth, shines at apparent magnitude 8.39, has spectral type G8 V and has an equilibrium temperature near 815 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 8.39, it is an easy target for binoculars.

Like any astronomical target, HD 20003 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 20003 b is an uncommon exoplanet

HD 20003 b scores 24 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 10 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Sub-Neptune, Multi-planet system and Orbits a Sun-like star — 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.