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Rare exoplanet 36 EP

HD 16905 b

RA 40.0136° · Dec -61.3550° · exoplanet

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Score breakdown

· 5 badges
36 pts · Rare
Rare 50 pts → Epic
  • Long-period world +10
  • Eccentric orbit +9
  • Frozen world +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 36

14 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Long-period world · +10
  • Eccentric orbit · +9

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

  • Denser than iron. It is packed tighter than solid iron — whatever it is made of, it is not ordinary rock.

What it actually is

  • What it is made of. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.

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 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 October — that's when to go looking.

Could we get there?

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

Properties

density gcc
10.4
diameter km
158176.88
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2022
dist ly
129.6147
eccentricity
0.68
eq temp k
69.63
host star teff
4866.12
inclination
43
insolation
0.0039
mag
9.44
mass earth
3591.461
name
HD 16905 b
orbital period days
10256
radius earth
12.4
semi major au
8.8
spect
K3 V
sys num planets
1
sys num stars
1

About HD 16905 b

HD 16905 b is a rare exoplanet. It lies about 129.6 light-years from Earth, shines at apparent magnitude 9.44, has spectral type K3 V and has an equilibrium temperature near 70 K.

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

How to see it

At apparent magnitude 9.44, a small backyard telescope will bring it into view.

Like any astronomical target, HD 16905 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 16905 b is a rare exoplanet

HD 16905 b scores 36 points on Spacedle's rarity scale, which places it in the rare tier. Another 14 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Frozen world, Long-period world and Eccentric orbit — 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.