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Uncommon exoplanet 22 EP

GJ 720 A b

RA 278.8294° · Dec 45.7456° · exoplanet

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Score breakdown

· 3 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Two suns in its sky +12
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 22

12 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Two suns in its sky · +12

Trivia

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

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

  • How to spot it. At magnitude 9.8 you'll want a small backyard telescope.
  • 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 June — 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. ≈ 891.7 thousand years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.4
diameter km
48090.874
discovery facility
Roque de los Muchachos Observatory
discovery method
Radial Velocity
discovery year
2021
dist ly
50.7417
eccentricity
0.12
eq temp k
401
host star teff
3837
insolation
4.2846
mag
9.84
mass earth
13.64
multi star system
yes
name
GJ 720 A b
orbital period days
19.466
radius earth
3.77
semi major au
0.119
spect
M0.5 V
sys num planets
1
sys num stars
2

About GJ 720 A b

GJ 720 A b is an uncommon exoplanet. It lies about 50.7 light-years from Earth, shines at apparent magnitude 9.84, has spectral type M0.5 V and has an equilibrium temperature near 401 K.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 9.84, a small backyard telescope will bring it into view.

Like any astronomical target, GJ 720 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 GJ 720 A b is an uncommon exoplanet

GJ 720 A b scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Sub-Neptune and Two suns in its sky — 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.