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Uncommon exoplanet 23 EP

HD 66428 b

RA 120.8692° · Dec -1.1636° · exoplanet

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Score breakdown

· 4 badges
23 pts · Uncommon
Uncommon 34 pts → Rare
  • Orbits a Sun-like star +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 23

11 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6
  • Orbits a Sun-like star · +8

Trivia

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.
  • 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 8.2 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around January — that's when to go looking.

Could we get there?

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

Properties

density gcc
10
diameter km
158176.88
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
discovery year
2005
dist ly
173.7815
eccentricity
0.471
eq temp k
159.02
host star teff
5716
inclination
16.639
insolation
0.1082
mag
8.25
mass earth
3478.9497
name
HD 66428 b
orbital period days
2269.8173
radius earth
12.4
semi major au
3.395
spect
G8 IV (+ G)
sys num planets
2
sys num stars
1

About HD 66428 b

HD 66428 b is an uncommon exoplanet. It lies about 173.8 light-years from Earth, shines at apparent magnitude 8.25, has spectral type G8 IV (+ G) and has an equilibrium temperature near 159 K.

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

How to see it

At apparent magnitude 8.25, it is an easy target for binoculars.

Like any astronomical target, HD 66428 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 66428 b is an uncommon exoplanet

HD 66428 b scores 23 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 11 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, 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.