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Uncommon exoplanet 27 EP

HD 139357 b

RA 233.8174° · Dec 53.9222° · exoplanet

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Score breakdown

· 3 badges
27 pts · Uncommon
Uncommon 33 pts → Rare
  • Denser than iron +18
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 27

6 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Denser than iron · +18

Trivia

What makes it special

  • Heavyweight. Packed denser than solid iron.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 6.4 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 570.8 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 3656 years in a starship at a tenth of light speed.
  • Distance. 366 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1660.

Saying hello

  • Say hello. A radio message and its reply would take 731 years round-trip.

Standing on it

  • A year here. A full year lasts about 3.1 Earth years.

By the numbers

  • Size. About 12.1× the width of Earth.
  • Volume. About 1772 Earths could fit inside it.
  • Mass. Roughly 6316× Earth's mass — about 19.9 Jupiters.
  • Your weight. You'd weigh about 43.1× your Earth weight standing here.
  • Density. Denser than solid iron.
  • Temperature. A scorching 174°C on average.

How we found it

  • Discovery. Found by Thueringer Landessternwarte Tautenburg using the radial velocity method.

Properties

density gcc
19.6
discovery facility
Thueringer Landessternwarte Tautenburg
discovery method
Radial Velocity
dist ly
365.5883
eccentricity
0.099
eq temp k
446.97
insolation
7.649
mass earth
6315.5683
name
HD 139357 b
orbital period days
1124.7914
radius earth
12.1
sys num planets
1

About HD 139357 b

HD 139357 b is an uncommon exoplanet. It lies about 365.6 light-years from Earth, has an equilibrium temperature near 447 K, spans roughly 12.1 Earth radii and weighs about 6,315.57 Earth masses.

Packed denser than solid iron.

How to see it

Like any astronomical target, HD 139357 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 139357 b is an uncommon exoplanet

HD 139357 b scores 27 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 6 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Gas giant and Denser than iron — 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.