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Rare exoplanet 45 EP

HD 125612 b

RA 215.2227° · Dec -17.4818° · 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. ≈ 3.3 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 293.4 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 1879 years in a starship at a tenth of light speed.
  • Distance. 188 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1838.

Saying hello

  • Say hello. A radio message and its reply would take 376 years round-trip.

Standing on it

  • A year here. A full year lasts just 558 Earth days.

By the numbers

  • Size. About 13.2× the width of Earth.
  • Volume. About 2300 Earths could fit inside it.
  • Mass. Roughly 945× Earth's mass — about 3 Jupiters.
  • Your weight. You'd weigh about 5.4× your Earth weight standing here.
  • Temperature. A surprisingly temperate -20°C average.

How we found it

  • Discovery. Found by W. M. Keck Observatory using the radial velocity method.

Cosmic context

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

Properties

density gcc
2.26
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
dist ly
187.9334
eccentricity
0.446
eq temp k
253.38
habitable zone
yes
insolation
0.6309
mass earth
945.2217
name
HD 125612 b
orbital period days
557.6999
radius earth
13.2
sys num planets
3

About HD 125612 b

HD 125612 b is a rare exoplanet. It lies about 187.9 light-years from Earth, has an equilibrium temperature near 253 K, spans roughly 13.2 Earth radii and weighs about 945.22 Earth masses.

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

How to see it

Like any astronomical target, HD 125612 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 125612 b is a rare exoplanet

HD 125612 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.

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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.