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Anomaly exoplanet 88 EP

KOI-55 b

RA 296.3562° · Dec 41.0927° · exoplanet

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Score breakdown

· 9 badges
88 pts · Anomaly
Anomaly 120 pts → Mythic
  • Ultra-hot Jupiter +26
  • Ultra-short period +14
  • Orbits a hot blue-white star +14
  • Disputed — it may not be there at all +10
  • Distant (over 1,000 light-years) +6
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Blasted by starlight +4
  • Found by Kepler +3
Total score 88

32 more points to reach Mythic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Ultra-hot Jupiter · +26
  • Ultra-short period · +14
  • Multi-planet system · +6
  • Blasted by starlight · +4
  • Found by Kepler · +3
  • Orbits a hot blue-white star · +14
  • Disputed — it may not be there at all · +10

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

  • A year in a day. Its entire year is over in 5.8 hours. Birthdays here would come round faster than meals.

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.
  • Crowded system. One of at least 2 planets orbiting its star.

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 15.2 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.

Properties

controversial
yes
density gcc
5.53
diameter km
9681.9558
discovery facility
Kepler
discovery method
Orbital Brightness Modulation
discovery year
2011
dist ly
4015.0456
eq temp k
7777.78
host star teff
27730
inclination
65
insolation
636352.1258
mag
15.154
mass earth
0.44
name
KOI-55 b
orbital period days
0.2401
radius earth
0.759
semi major au
0.006
spect
B
sys num planets
2
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About KOI-55 b

KOI-55 b is an anomaly exoplanet. It lies about 4,015 light-years from Earth, shines at apparent magnitude 15.15, has spectral type B and has an equilibrium temperature near 7,778 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 15.15, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, KOI-55 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 KOI-55 b is an anomaly exoplanet

KOI-55 b scores 88 points on Spacedle's rarity scale, which places it in the anomaly tier. Another 32 points would lift it into a rarer tier.

That score comes from 9 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Ultra-hot Jupiter, Ultra-short period, Multi-planet system, Blasted by starlight, Found by Kepler and Orbits a hot blue-white star — 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.