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Common exoplanet 18 EP

HD 168009 b

RA 273.8848° · Dec 45.2088° · exoplanet

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Score breakdown

· 3 badges
18 pts · Common
Common 22 pts → Uncommon
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 18

4 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Orbits a Sun-like star · +8

Trivia

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. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.

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 6.3 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 June — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 1.3 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.85
diameter km
38906.41
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2021
dist ly
76.0048
eccentricity
0.12
eq temp k
887.57
host star teff
5778.33
insolation
99.3735
mag
6.295
mass earth
9.5349
name
HD 168009 b
orbital period days
15.1479
radius earth
3.05
semi major au
0.1192
spect
G2V
sys num planets
1
sys num stars
1

Nearby objects

About HD 168009 b

HD 168009 b is a common exoplanet. It lies about 76 light-years from Earth, shines at apparent magnitude 6.29, has spectral type G2V and has an equilibrium temperature near 888 K.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 6.29, it is an easy target for binoculars.

Like any astronomical target, HD 168009 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 168009 b is a common exoplanet

HD 168009 b scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Sub-Neptune 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.