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Rare exoplanet 33 EP

HD 41004 B b

RA 89.9566° · Dec -48.2394° · exoplanet

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Score breakdown

· 4 badges
33 pts · Rare
Rare 46 pts → Epic
  • Denser than iron +18
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 33

13 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Denser than iron · +18
  • Multi-planet system · +6

Trivia

What makes it special

  • Heavyweight. Packed denser than solid iron.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 2.4 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 211.6 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 1355 years in a starship at a tenth of light speed.
  • Distance. 136 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1890.

Saying hello

  • Say hello. A radio message and its reply would take 271 years round-trip.

Standing on it

  • A year here. A full year lasts just 1.3 Earth days.

By the numbers

  • Size. About 12.1× the width of Earth.
  • Volume. About 1772 Earths could fit inside it.
  • Mass. Roughly 5838× Earth's mass — about 18.4 Jupiters.
  • Your weight. You'd weigh about 39.9× your Earth weight standing here.
  • Density. Denser than solid iron.

How we found it

  • Discovery. Found by La Silla Observatory using the radial velocity method.

Cosmic context

  • Crowded system. One of at least 2 planets orbiting its star.

Properties

density gcc
18.1
discovery facility
La Silla Observatory
discovery method
Radial Velocity
dist ly
135.5191
eccentricity
0.081
mass earth
5838.29
name
HD 41004 B b
orbital period days
1.3283
radius earth
12.1
sys num planets
2

About HD 41004 B b

HD 41004 B b is a rare exoplanet. It lies about 135.5 light-years from Earth, spans roughly 12.1 Earth radii, weighs about 5,838.29 Earth masses and completes an orbit every 1.33 days.

Packed denser than solid iron.

How to see it

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 a rare exoplanet

HD 41004 B b scores 33 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Denser than iron and Multi-planet system — 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.