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Rare exoplanet 35 EP

XO-2 S b

RA 117.0310° · Dec 50.2169° · exoplanet

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Score breakdown

· 5 badges
35 pts · Rare
Rare 50 pts → Epic
  • Two suns in its sky +12
  • Orbits a Sun-like star +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 35

15 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6
  • Orbits a Sun-like star · +8
  • Two suns in its sky · +12

Trivia

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

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.
  • Crowded system. One of at least 4 planets orbiting its star.

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 11.2 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 January — that's when to go looking.

Properties

density gcc
0.351
diameter km
139042.58
discovery facility
Roque de los Muchachos Observatory
discovery method
Radial Velocity
discovery year
2014
dist ly
493.7937
eccentricity
0.15
eq temp k
706.59
host star teff
5325
insolation
41.519
mag
11.196
mass earth
82.6354
multi star system
yes
name
XO-2 S b
orbital period days
18.22
radius earth
10.9
semi major au
0.1347
spect
G8 V
sys num planets
4
sys num stars
2

About XO-2 S b

XO-2 S b is a rare exoplanet. It lies about 493.8 light-years from Earth, shines at apparent magnitude 11.2, has spectral type G8 V and has an equilibrium temperature near 707 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 11.2, a small backyard telescope will bring it into view.

Like any astronomical target, XO-2 S 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 XO-2 S b is a rare exoplanet

XO-2 S b scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Multi-planet system, Orbits a Sun-like star 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.