Rare exoplanet 45 EP

47 UMa b

RA 164.8648° · Dec 40.4305° · exoplanet

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Score breakdown

· 4 badges

45 pts · Rare

Rare 46 pts → Epic

In the habitable zone +30
Multi-planet system +6
Confirmed exoplanet +5
Gas giant +4

Total score 45

1 more point to reach Epic.

Badges

Confirmed exoplanet · +5
In the habitable zone · +30
Gas giant · +4
Multi-planet system · +6

Trivia

What makes it special

Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist.

Could we get there?

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

Getting there

Aboard Voyager 1. ≈ 790.8 thousand years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 70.3 thousand years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 450 years in a starship at a tenth of light speed.
Distance. 45 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1981.

Saying hello

Say hello. A radio message and its reply would take 90 years round-trip.

Standing on it

A year here. A full year lasts about 3 Earth years.

By the numbers

Size. About 13.2× the width of Earth.
Volume. About 2300 Earths could fit inside it.
Mass. Roughly 804× Earth's mass — about 2.5 Jupiters.
Your weight. You'd weigh about 4.6× your Earth weight standing here.
Temperature. A frigid -58°C — colder than dry ice.

How we found it

Discovery. Found by Lick Observatory using the radial velocity method.

Cosmic context

Crowded system. One of at least 3 planets orbiting its star.

Properties

density gcc: 1.92
discovery facility: Lick Observatory
discovery method: Radial Velocity
dist ly: 44.9988
eccentricity: 0.032
eq temp k: 215.23
habitable zone: yes
insolation: 0.3576
mass earth: 804.08
name: 47 UMa b
orbital period days: 1078
radius earth: 13.2
sys num planets: 3

About 47 UMa b

47 UMa b is a rare exoplanet. It lies about 45 light-years from Earth, has an equilibrium temperature near 215 K, spans roughly 13.2 Earth radii and weighs about 804.08 Earth masses.

Sits where it's neither too hot nor too cold — liquid water could exist.

How to see it

Like any astronomical target, 47 UMa 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 47 UMa b is a rare exoplanet

47 UMa b scores 45 points on Spacedle's rarity scale, which places it in the rare tier. Another 1 point would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, In the habitable zone, Gas giant and Multi-planet system — 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.