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Common exoplanet 19 EP

HAT-P-54 b

RA 99.8980° · Dec 25.4824° · exoplanet

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Score breakdown

· 3 badges
19 pts · Common
Common 22 pts → Uncommon
  • Tidally locked +10
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 19

3 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Tidally locked · +10

Trivia

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 13.4 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 December — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 8.2 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.118
diameter km
134977.128
discovery facility
HATNet
discovery method
Transit
discovery year
2015
dist ly
468.5264
eccentricity
0.074
eq temp k
818
host star teff
4390
inclination
87.04
insolation
88.6713
mag
13.398
mass earth
241.5508
name
HAT-P-54 b
orbital period days
3.7998
radius earth
10.5813
semi major au
0.0412
spect
K7
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About HAT-P-54 b

HAT-P-54 b is a common exoplanet. It lies about 468.5 light-years from Earth, shines at apparent magnitude 13.4, has spectral type K7 and has an equilibrium temperature near 818 K.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 13.4, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, HAT-P-54 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 HAT-P-54 b is a common exoplanet

HAT-P-54 b scores 19 points on Spacedle's rarity scale, which places it in the common tier. Another 3 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Gas giant and Tidally locked — 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.