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Epic exoplanet 55 EP

GPX-1 b

RA 38.3692° · Dec 56.0257° · exoplanet

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Score breakdown

· 6 badges
55 pts · Epic
Epic 78 pts → Anomaly
  • Ultra-hot Jupiter +26
  • Tidally locked +10
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Blasted by starlight +4
Total score 55

23 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Ultra-hot Jupiter · +26
  • Tidally locked · +10
  • Blasted by starlight · +4

Trivia

What makes it special

  • Ultra-hot Jupiter. So hot that iron vaporises on the dayside, blows around to the night side and rains back down as molten metal.

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.

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 12.3 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • 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 October — that's when to go looking.

Properties

density gcc
8.2224
diameter km
210186.4794
discovery facility
Acton Sky Portal Observatory
discovery method
Transit
discovery year
2021
dist ly
2136.3642
eccentricity
0
eq temp k
2300
host star teff
7000
inclination
79.9
insolation
4650
mag
12.316
mass earth
6261.2196
name
GPX-1 b
orbital period days
1.7446
radius earth
16.4772
semi major au
0.0338
spect
F2
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About GPX-1 b

GPX-1 b is an epic exoplanet. It lies about 2,136.4 light-years from Earth, shines at apparent magnitude 12.32, has spectral type F2 and has an equilibrium temperature near 2,300 K.

So hot that iron vaporises on the dayside, blows around to the night side and rains back down as molten metal.

How to see it

At apparent magnitude 12.32, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, GPX-1 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 GPX-1 b is an epic exoplanet

GPX-1 b scores 55 points on Spacedle's rarity scale, which places it in the epic tier. Another 23 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant, Ultra-hot Jupiter, Tidally locked and Blasted by starlight — 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.