← Back to dex
Uncommon exoplanet 27 EP

HD 41004 B b

RA 89.9566° · Dec -48.2394° · exoplanet

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 4 badges
27 pts · Uncommon
Uncommon 34 pts → Rare
  • Two suns in its sky +12
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 27

7 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6
  • Two suns in its sky · +12

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

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • 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 8.6 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • 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 December — that's when to go looking.

Properties

density gcc
18.1
diameter km
154350.02
discovery facility
La Silla Observatory
discovery method
Radial Velocity
discovery year
2003
dist ly
135.5191
eccentricity
0.081
host star teff
5036
mag
8.6078
mass earth
5838.29
multi star system
yes
name
HD 41004 B b
orbital period days
1.3283
radius earth
12.1
spect
M2 V
sys num planets
2
sys num stars
2

About HD 41004 B b

HD 41004 B b is an uncommon exoplanet. It lies about 135.5 light-years from Earth, shines at apparent magnitude 8.61, has spectral type M2 V and spans roughly 12.1 Earth radii.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 8.61, it is an easy target for binoculars.

Like any astronomical target, HD 41004 B 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 41004 B b is an uncommon exoplanet

HD 41004 B 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, Multi-planet system and Two suns in its sky — 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.