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Rare exoplanet 43 EP

K2-210 b

RA 17.6413° · Dec 1.5784° · exoplanet

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Score breakdown

· 4 badges
43 pts · Rare
Rare 50 pts → Epic
  • Earth-sized +16
  • Ultra-short period +14
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
Total score 43

7 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Earth-sized · +16
  • Ultra-short period · +14
  • Orbits a Sun-like star · +8

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 13.7 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. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.

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 11.5 you'll want a small backyard telescope.
  • 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 October — that's when to go looking.

Properties

density gcc
4.89
diameter km
10970.332
discovery facility
K2
discovery method
Transit
discovery year
2018
dist ly
575.698
host star teff
5500
inclination
89.2
mag
11.535
mass earth
0.566
name
K2-210 b
orbital period days
0.5702
radius earth
0.86
sys num planets
1
sys num stars
1

Nearby objects

About K2-210 b

K2-210 b is a rare exoplanet. It lies about 575.7 light-years from Earth, shines at apparent magnitude 11.54, spans roughly 0.86 Earth radii and weighs about 0.57 Earth masses.

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 11.54, a small backyard telescope will bring it into view.

Like any astronomical target, K2-210 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 K2-210 b is a rare exoplanet

K2-210 b scores 43 points on Spacedle's rarity scale, which places it in the rare tier. Another 7 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Earth-sized, Ultra-short period and Orbits a Sun-like 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.