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Uncommon exoplanet 27 EP

HD 29985 b

RA 70.5217° · Dec -33.9211° · exoplanet

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Score breakdown

· 4 badges
27 pts · Uncommon
Uncommon 34 pts → Rare
  • Long-period world +10
  • Frozen world +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 27

7 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Long-period world · +10

Trivia

What makes it special

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

What it actually is

  • What it is made of. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.

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 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 November — 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. ≈ 1.8 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
4.56
diameter km
163279.36
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2022
dist ly
101.9913
eccentricity
0.261
eq temp k
46.73
host star teff
4678
inclination
52.658
insolation
0.0008
mag
9.98
mass earth
1739.4749
name
HD 29985 b
orbital period days
20608.1405
radius earth
12.8
semi major au
13.39
sys num planets
1
sys num stars
1

About HD 29985 b

HD 29985 b is an uncommon exoplanet. It lies about 102 light-years from Earth, shines at apparent magnitude 9.98, has an equilibrium temperature near 47 K and spans roughly 12.8 Earth radii.

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

How to see it

At apparent magnitude 9.98, a small backyard telescope will bring it into view.

Like any astronomical target, HD 29985 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 29985 b is an uncommon exoplanet

HD 29985 b scores 27 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 7 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Frozen world and Long-period world — 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.