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Common exoplanet 15 EP

HD 12661 b

RA 31.1424° · Dec 25.4136° · exoplanet

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Score breakdown

· 3 badges
15 pts · Common
Common 24 pts → Uncommon
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 15

9 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 2.2 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 192.7 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 1234 years in a starship at a tenth of light speed.
  • Distance. 123 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1903.

Saying hello

  • Say hello. A radio message and its reply would take 247 years round-trip.

Standing on it

  • A year here. A full year lasts just 263 Earth days.

By the numbers

  • Size. About 13.3× the width of Earth.
  • Volume. About 2353 Earths could fit inside it.
  • Mass. Roughly 772× Earth's mass — about 2.4 Jupiters.
  • Your weight. You'd weigh about 4.4× your Earth weight standing here.
  • Temperature. A scorching 52°C on average.

How we found it

  • Discovery. Found by Multiple Observatories using the radial velocity method.

Cosmic context

  • Crowded system. One of at least 2 planets orbiting its star.

Properties

density gcc
1.8
discovery facility
Multiple Observatories
discovery method
Radial Velocity
dist ly
123.4429
eccentricity
0.38
eq temp k
325.35
insolation
1.9237
mass earth
772.3269
name
HD 12661 b
orbital period days
262.7086
radius earth
13.3
sys num planets
2

About HD 12661 b

HD 12661 b is a common exoplanet. It lies about 123.4 light-years from Earth, has an equilibrium temperature near 325 K, spans roughly 13.3 Earth radii and weighs about 772.33 Earth masses.

One of at least 2 planets orbiting its star.

How to see it

Like any astronomical target, HD 12661 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 12661 b is a common exoplanet

HD 12661 b scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 9 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, 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.