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Uncommon exoplanet 33 EP

WISEP J121756.91+162640.2 A b

RA 184.4871° · Dec 16.4445° · exoplanet

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Score breakdown

· 4 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Directly imaged +16
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 33

1 more point to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Directly imaged · +16
  • Orbits a red dwarf · +8

Trivia

Hard to believe

  • Denser than iron. It is packed tighter than solid iron — whatever it is made of, it is not ordinary rock.

What it actually is

  • What it is made of. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around March — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 578.9 thousand years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 51.4 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

density gcc
33.5
diameter km
133531.9016
discovery facility
W. M. Keck Observatory
discovery method
Imaging
discovery year
2012
dist ly
32.9418
eq temp k
450
host star teff
575
insolation
0
mass earth
6992
name
WISEP J121756.91+162640.2 A b
radius earth
10.468
semi major au
8
spect
T8.5
sys num planets
1
sys num stars
1

Nearby objects

About WISEP J121756.91+162640.2 A b

WISEP J121756.91+162640.2 A b is an uncommon exoplanet. It lies about 32.9 light-years from Earth, has spectral type T8.5, has an equilibrium temperature near 450 K and spans roughly 10.47 Earth radii.

Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.

How to see it

Like any astronomical target, WISEP J121756.91+162640.2 A 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 WISEP J121756.91+162640.2 A b is an uncommon exoplanet

WISEP J121756.91+162640.2 A b scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Directly imaged and Orbits a red dwarf — 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.