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Rare exoplanet 49 EP

HAT-P-27 b

RA 222.7673° · Dec 5.9474° · exoplanet

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Score breakdown

· 6 badges
49 pts · Rare
Rare 50 pts → Epic
  • Two suns in its sky +12
  • Hot Jupiter +10
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 49

1 more point to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Tidally locked · +10
  • Orbits a Sun-like star · +8
  • Two suns in its sky · +12

Trivia

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 12.1 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around May — that's when to go looking.

Could we get there?

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

Properties

density gcc
0.76
diameter km
145803.366
discovery facility
HATNet
discovery method
Transit
discovery year
2011
dist ly
649.6147
eccentricity
0
eq temp k
1091.99
host star teff
5316
inclination
85
insolation
336.0384
mag
12.052
mass earth
197.05
multi star system
yes
name
HAT-P-27 b
orbital period days
3.0396
radius earth
11.43
semi major au
0.04
spect
G8
sys num planets
1
sys num stars
2
tidally locked
yes
tidally locked inferred
yes

About HAT-P-27 b

HAT-P-27 b is a rare exoplanet. It lies about 649.6 light-years from Earth, shines at apparent magnitude 12.05, has spectral type G8 and has an equilibrium temperature near 1,092 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 12.05, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, HAT-P-27 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-27 b is a rare exoplanet

HAT-P-27 b scores 49 points on Spacedle's rarity scale, which places it in the rare tier. Another 1 point would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Tidally locked, Orbits a Sun-like star and Two suns in its sky — 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.