← Back to dex
Uncommon exoplanet 25 EP

HD 290327 b

RA 80.8400° · Dec -2.2780° · exoplanet

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

Computing the sky for your location…

Score breakdown

· 4 badges
25 pts · Uncommon
Uncommon 34 pts → Rare
  • Frozen world +8
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 25

9 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Orbits a Sun-like star · +8

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. 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. 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 9 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • 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 December — 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. ≈ 3.2 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.8
diameter km
169657.46
discovery facility
La Silla Observatory
discovery method
Radial Velocity
discovery year
2009
dist ly
184.0596
eccentricity
0.08
eq temp k
139.7
host star teff
5505
insolation
0.0616
mag
8.99
mass earth
772.3269
name
HD 290327 b
orbital period days
2443
radius earth
13.3
semi major au
3.43
spect
G8 V
sys num planets
1
sys num stars
1

Nearby objects

About HD 290327 b

HD 290327 b is an uncommon exoplanet. It lies about 184.1 light-years from Earth, shines at apparent magnitude 8.99, has spectral type G8 V and has an equilibrium temperature near 140 K.

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

How to see it

At apparent magnitude 8.99, it is an easy target for binoculars.

Like any astronomical target, HD 290327 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 290327 b is an uncommon exoplanet

HD 290327 b scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Frozen world 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.