← Back to dex
Uncommon exoplanet 33 EP

BD-210397 c

RA 33.3024° · Dec -21.1962° · exoplanet

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 5 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Long-period world +10
  • Frozen world +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 33

1 more point to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Long-period world · +10
  • Multi-planet system · +6

Trivia

What makes it special

  • Frozen world. A deep-frozen world, too far from its star's warmth for anything to stay liquid.

What it actually is

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

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 9.8 you'll want a small backyard telescope.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around October — that's when to go looking.

Could we get there?

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

Properties

density gcc
3.91
diameter km
164554.98
discovery facility
La Silla Observatory
discovery method
Radial Velocity
discovery year
2023
dist ly
77.4046
eccentricity
0.43
eq temp k
69.51
host star teff
4051
inclination
33
insolation
0.0039
mag
9.84
mass earth
1525.5764
name
BD-210397 c
orbital period days
6240
radius earth
12.9
semi major au
5.9
spect
K7 V
sys num planets
2
sys num stars
1

About BD-210397 c

BD-210397 c is an uncommon exoplanet. It lies about 77.4 light-years from Earth, shines at apparent magnitude 9.84, has spectral type K7 V and has an equilibrium temperature near 70 K.

A deep-frozen world, too far from its star's warmth for anything to stay liquid.

How to see it

At apparent magnitude 9.84, a small backyard telescope will bring it into view.

Like any astronomical target, BD-210397 c 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 BD-210397 c is an uncommon exoplanet

BD-210397 c scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Frozen world, Long-period world and Multi-planet system — 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.