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Common exoplanet 19 EP

8 UMi b

RA 224.2017° · Dec 74.9009° · exoplanet

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Score breakdown

· 3 badges
19 pts · Common
Common 22 pts → Uncommon
  • Hot Jupiter +10
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 19

3 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10

Trivia

What it actually is

  • What it is made of. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

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 6.8 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around May — 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. ≈ 9.3 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 827.8 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

density gcc
1.17
diameter km
172208.7
discovery facility
Bohyunsan Optical Astronomical Observatory
discovery method
Radial Velocity
discovery year
2015
dist ly
530.1731
eccentricity
0.062
eq temp k
1126.38
host star teff
4847
insolation
247.8402
mag
6.833
mass earth
524.4169
name
8 UMi b
orbital period days
93.31
radius earth
13.5
semi major au
0.462
spect
K0
sys num planets
1
sys num stars
1

About 8 UMi b

8 UMi b is a common exoplanet. It lies about 530.2 light-years from Earth, shines at apparent magnitude 6.83, has spectral type K0 and has an equilibrium temperature near 1,126 K.

Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

How to see it

At apparent magnitude 6.83, it is an easy target for binoculars.

Like any astronomical target, 8 UMi 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 8 UMi b is a common exoplanet

8 UMi b scores 19 points on Spacedle's rarity scale, which places it in the common tier. Another 3 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Gas giant and Hot Jupiter — 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.