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Uncommon exoplanet 25 EP

HD 240237 b

RA 348.9259° · Dec 58.0432° · exoplanet

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Score breakdown

· 4 badges
25 pts · Uncommon
Uncommon 34 pts → Rare
  • Hot Jupiter +10
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 25

9 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Hot Jupiter · +10

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.

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.
  • 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 September — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 53.5 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
15.3
diameter km
155625.64
discovery facility
McDonald Observatory
discovery method
Radial Velocity
discovery year
2011
dist ly
3044.2651
eccentricity
0.4
eq temp k
1153.09
host star teff
3926
insolation
83.8296
mag
8.19
mass earth
5050.3187
name
HD 240237 b
orbital period days
745.7
radius earth
12.2
semi major au
1.92
spect
K2 III
sys num planets
1
sys num stars
1

Nearby objects

About HD 240237 b

HD 240237 b is an uncommon exoplanet. It lies about 3,044.3 light-years from Earth, shines at apparent magnitude 8.19, has spectral type K2 III and has an equilibrium temperature near 1,153 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 8.19, it is an easy target for binoculars.

Like any astronomical target, HD 240237 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 240237 b is an uncommon exoplanet

HD 240237 b scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant and Hot Jupiter — 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.