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Uncommon exoplanet 31 EP

tau Gem b

RA 107.7847° · Dec 30.2450° · exoplanet

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Score breakdown

· 4 badges
31 pts · Uncommon
Uncommon 34 pts → Rare
  • Its star is visible to the naked eye +12
  • Hot Jupiter +10
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 31

3 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Its star is visible to the naked eye · +12

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. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 4.4 you can see it with your own eyes from a dark site.
  • 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 January — 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. ≈ 6.5 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
20.3
diameter km
154350.02
discovery facility
Lick Observatory
discovery method
Radial Velocity
discovery year
2013
dist ly
367.0462
eccentricity
0.031
eq temp k
1012.69
host star teff
4388
insolation
241.3109
mag
4.378
mass earth
6547
name
tau Gem b
orbital period days
305.5
radius earth
12.1
semi major au
1.17
spect
K2 III
sys num planets
1
sys num stars
1

About tau Gem b

tau Gem b is an uncommon exoplanet. It lies about 367 light-years from Earth, shines at apparent magnitude 4.38, has spectral type K2 III and has an equilibrium temperature near 1,013 K.

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

How to see it

At apparent magnitude 4.38, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, tau Gem 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 tau Gem b is an uncommon exoplanet

tau Gem b scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter and Its star is visible to the naked eye — 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.