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Anomaly exoplanet 81 EP

HD 100546 b

RA 173.3555° · Dec -70.1948° · exoplanet

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Score breakdown

· 8 badges
81 pts · Anomaly
Anomaly 120 pts → Mythic
  • Directly imaged +16
  • Orbits a hot blue-white star +14
  • Puffy low-density world +12
  • Orbits beyond Neptune's distance +12
  • Disputed — it may not be there at all +10
  • Frozen world +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 81

39 more points to reach Mythic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Puffy low-density world · +12
  • Directly imaged · +16
  • Orbits a hot blue-white star · +14
  • Orbits beyond Neptune's distance · +12
  • Disputed — it may not be there at all · +10

Trivia

What makes it special

  • Frozen world. A deep-frozen world, too far from its star's warmth for anything to stay liquid.

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.

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 6.7 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 March — that's when to go looking.

Could we get there?

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

Properties

controversial
yes
density gcc
0.0321
diameter km
986591.296
discovery facility
Paranal Observatory
discovery method
Imaging
discovery year
2014
dist ly
357.7181
eq temp k
94.67
host star teff
10500
insolation
0.0113
mag
6.69
mass earth
2701.5415
name
HD 100546 b
radius earth
77.3421
semi major au
53
spect
B9 Vne
sys num planets
1
sys num stars
1

About HD 100546 b

HD 100546 b is an anomaly exoplanet. It lies about 357.7 light-years from Earth, shines at apparent magnitude 6.69, has spectral type B9 Vne and has an equilibrium temperature near 95 K.

A deep-frozen world, too far from its star's warmth for anything to stay liquid.

How to see it

At apparent magnitude 6.69, it is an easy target for binoculars.

Like any astronomical target, HD 100546 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 100546 b is an anomaly exoplanet

HD 100546 b scores 81 points on Spacedle's rarity scale, which places it in the anomaly tier. Another 39 points would lift it into a rarer tier.

That score comes from 8 science badges — Confirmed exoplanet, Gas giant, Frozen world, Puffy low-density world, Directly imaged, Orbits a hot blue-white star, Orbits beyond Neptune's distance and Disputed — it may not be there at all — 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.