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Common exoplanet 15 EP

HD 240210 b

RA 347.6219° · Dec 57.0295° · exoplanet

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Score breakdown

· 3 badges
15 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 15

7 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4

Trivia

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.

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 8.3 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • 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 September — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 21.3 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.9 million years even at the Parker Solar Probe's 192 km/s.

Properties

density gcc
4.34
diameter km
163279.36
discovery facility
McDonald Observatory
discovery method
Radial Velocity
discovery year
2009
dist ly
1214.6213
eccentricity
0.15
eq temp k
970.67
host star teff
4297
insolation
26.3684
mag
8.27
mass earth
1655.82
name
HD 240210 b
orbital period days
501.75
radius earth
12.8
semi major au
1.16
spect
K3 III
sys num planets
1
sys num stars
1

Nearby objects

About HD 240210 b

HD 240210 b is a common exoplanet. It lies about 1,214.6 light-years from Earth, shines at apparent magnitude 8.27, has spectral type K3 III and has an equilibrium temperature near 971 K.

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

How to see it

At apparent magnitude 8.27, it is an easy target for binoculars.

Like any astronomical target, HD 240210 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 HD 240210 b is a common exoplanet

HD 240210 b scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Distant (over 1,000 light-years) and Gas giant — 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.