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Epic exoplanet 47 EP

HD 240237 b

RA 348.9259° · Dec 58.0432° · exoplanet

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Score breakdown

· 5 badges
47 pts · Epic
Epic 68 pts → Anomaly
  • Denser than iron +18
  • Hot Jupiter +10
  • Distant (>1000 ly) +10
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 47

21 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Denser than iron · +18
  • Distant (>1000 ly) · +10

Trivia

What makes it special

  • Heavyweight. Packed denser than solid iron.

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).
  • Fastest probe ever. ≈ 4.8 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 30.4 thousand years in a starship at a tenth of light speed.
  • Distance. 3044 light-years from Earth.

Look-back time

  • Look-back time. Its light left before the last ice age ended.

Saying hello

  • Say hello. A radio message and its reply would take 6089 years round-trip.

Standing on it

  • A year here. A full year lasts about 2 Earth years.

By the numbers

  • Size. About 12.2× the width of Earth.
  • Volume. About 1816 Earths could fit inside it.
  • Mass. Roughly 5050× Earth's mass — about 15.9 Jupiters.
  • Your weight. You'd weigh about 33.9× your Earth weight standing here.
  • Density. Denser than solid iron.
  • Temperature. Around 880°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by McDonald Observatory using the radial velocity method.

Properties

density gcc
15.3
discovery facility
McDonald Observatory
discovery method
Radial Velocity
dist ly
3044.2651
eccentricity
0.4
eq temp k
1153.09
insolation
83.8296
mass earth
5050.3187
name
HD 240237 b
orbital period days
745.7
radius earth
12.2
sys num planets
1

About HD 240237 b

HD 240237 b is an epic exoplanet. It lies about 3,044.3 light-years from Earth, has an equilibrium temperature near 1,153 K, spans roughly 12.2 Earth radii and weighs about 5,050.32 Earth masses.

Packed denser than solid iron.

How to see it

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 epic exoplanet

HD 240237 b scores 47 points on Spacedle's rarity scale, which places it in the epic tier. Another 21 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Denser than iron and Distant (>1000 ly) — 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.