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Rare exoplanet 39 EP

24 Boo b

RA 217.1555° · Dec 49.8446° · exoplanet

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Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Lava world +14
  • Its star is visible to the naked eye +12
  • Confirmed exoplanet +5
  • Gas giant +4
  • Blasted by starlight +4
Total score 39

11 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Lava world · +14
  • Blasted by starlight · +4
  • Its star is visible to the naked eye · +12

Trivia

What makes it special

  • Lava world. Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

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. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

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 5.6 you can see it with your own eyes from a dark site.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around April — that's when to go looking.

Properties

density gcc
0.574
diameter km
177311.18
discovery facility
Okayama Astrophysical Observatory
discovery method
Radial Velocity
discovery year
2018
dist ly
313.0651
eccentricity
0.032
eq temp k
1840.86
host star teff
4816
insolation
2001.2754
mag
5.59
mass earth
280.6425
name
24 Boo b
orbital period days
30.33
radius earth
13.9
semi major au
0.194
spect
G3 IV
sys num planets
1
sys num stars
1

About 24 Boo b

24 Boo b is a rare exoplanet. It lies about 313.1 light-years from Earth, shines at apparent magnitude 5.59, has spectral type G3 IV and has an equilibrium temperature near 1,841 K.

Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

How to see it

At apparent magnitude 5.59, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 24 Boo 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 24 Boo b is a rare exoplanet

24 Boo b scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Lava world, Blasted by starlight and Its star is visible to the naked eye — 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.