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Rare exoplanet 44 EP

Kepler-1203 b

RA 292.7735° · Dec 44.1781° · exoplanet

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Score breakdown

· 5 badges
44 pts · Rare
Rare 50 pts → Epic
  • Earth-sized +16
  • Ultra-short period +14
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Found by Kepler +3
Total score 44

6 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Earth-sized · +16
  • Ultra-short period · +14
  • Found by Kepler · +3

Trivia

What makes it special

  • Earth-sized. Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

Hard to believe

  • A year in a day. Its entire year is over in 14.1 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.

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 15.4 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 July — that's when to go looking.

Properties

density gcc
5.54
diameter km
13521.572
discovery facility
Kepler
discovery method
Transit
discovery year
2016
dist ly
1033.9863
eccentricity
0
eq temp k
1188
host star teff
4105
inclination
83.78
insolation
723.806
mag
15.385
mass earth
1.2
name
Kepler-1203 b
orbital period days
0.588
radius earth
1.06
semi major au
0.0114
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About Kepler-1203 b

Kepler-1203 b is a rare exoplanet. It lies about 1,034 light-years from Earth, shines at apparent magnitude 15.38, has an equilibrium temperature near 1,188 K and spans roughly 1.06 Earth radii.

Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

How to see it

At apparent magnitude 15.38, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Kepler-1203 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 Kepler-1203 b is a rare exoplanet

Kepler-1203 b scores 44 points on Spacedle's rarity scale, which places it in the rare tier. Another 6 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Earth-sized, Ultra-short period and Found by Kepler — 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.