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Rare exoplanet 37 EP

XO-5 b

RA 116.7164° · Dec 39.0945° · exoplanet

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Score breakdown

· 5 badges
37 pts · Rare
Rare 50 pts → Epic
  • Hot Jupiter +10
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 37

13 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Tidally locked · +10
  • Orbits a Sun-like star · +8

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. 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 12.2 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • 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. ≈ 15.8 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.06
diameter km
163024.236
discovery facility
XO
discovery method
Transit
discovery year
2008
dist ly
900.8787
eccentricity
0
eq temp k
1230
host star teff
5430
inclination
86.8
insolation
397.4799
mag
12.198
mass earth
378.2
name
XO-5 b
orbital period days
4.1878
radius earth
12.78
semi major au
0.0515
spect
G8 V
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About XO-5 b

XO-5 b is a rare exoplanet. It lies about 900.9 light-years from Earth, shines at apparent magnitude 12.2, has spectral type G8 V and has an equilibrium temperature near 1,230 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 12.2, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, XO-5 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-5 b is a rare exoplanet

XO-5 b scores 37 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Tidally locked and Orbits a Sun-like star — 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.