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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 24 pts → Uncommon
  • Hot Jupiter +10
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 19

5 more points to reach Uncommon.

Badges

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

Trivia

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.
  • At 10% light speed. ≈ 5302 years in a starship at a tenth of light speed.
  • Distance. 530 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1496.

Saying hello

  • Say hello. A radio message and its reply would take 1060 years round-trip.

Standing on it

  • A year here. A full year lasts just 93.3 Earth days.

By the numbers

  • Size. About 13.5× the width of Earth.
  • Volume. About 2460 Earths could fit inside it.
  • Mass. Roughly 524× Earth's mass — about 1.7 Jupiters.
  • Your weight. You'd weigh about 2.9× your Earth weight standing here.
  • Temperature. Around 853°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by Bohyunsan Optical Astronomical Observatory using the radial velocity method.

Properties

density gcc
1.17
discovery facility
Bohyunsan Optical Astronomical Observatory
discovery method
Radial Velocity
dist ly
530.1731
eccentricity
0.062
eq temp k
1126.38
insolation
247.8402
mass earth
524.4169
name
8 UMi b
orbital period days
93.31
radius earth
13.5
sys num planets
1

About 8 UMi b

8 UMi b is a common exoplanet. It lies about 530.2 light-years from Earth, has an equilibrium temperature near 1,126 K, spans roughly 13.5 Earth radii and weighs about 524.42 Earth masses.

About 13.5× the width of Earth.

How to see it

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 5 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.

spacedle A daily roll through the real universe. © 2026 spacedle. Buy me a coffee

Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.