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Rare exoplanet 44 EP

HD 39091 b

RA 84.2993° · Dec -80.4646° · exoplanet

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Score breakdown

· 6 badges
44 pts · Rare
Rare 50 pts → Epic
  • Its star is visible to the naked eye +12
  • Eccentric orbit +9
  • Orbits a Sun-like star +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 44

6 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Eccentric orbit · +9
  • Multi-planet system · +6
  • Its star is visible to the naked eye · +12
  • 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 3 planets orbiting its star.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 5.7 you can see it with your own eyes from a dark site.
  • 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 December — that's when to go looking.

Could we get there?

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

Properties

density gcc
13.2
diameter km
156901.26
discovery facility
Anglo-Australian Telescope
discovery method
Radial Velocity
discovery year
2001
dist ly
59.5894
eccentricity
0.642
eq temp k
172.74
host star teff
5998
inclination
45.8
insolation
0.1342
mag
5.65
mass earth
4481.3805
name
HD 39091 b
orbital period days
2088.8
radius earth
12.3
semi major au
3.28
spect
G0 V
sys num planets
3
sys num stars
1

About HD 39091 b

HD 39091 b is a rare exoplanet. It lies about 59.6 light-years from Earth, shines at apparent magnitude 5.65, has spectral type G0 V and has an equilibrium temperature near 173 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 5.65, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HD 39091 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 39091 b is a rare exoplanet

HD 39091 b scores 44 points on Spacedle's rarity scale, which places it in the rare tier. Another 6 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Eccentric orbit, Multi-planet system, Its star is visible to the naked eye 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.