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Rare exoplanet 46 EP

Kepler-173 b

RA 294.6466° · Dec 41.8841° · exoplanet

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Score breakdown

· 7 badges
46 pts · Rare
Rare 50 pts → Epic
  • Tidally locked +10
  • Super-Earth +8
  • Orbits a Sun-like star +8
  • Distant (over 1,000 light-years) +6
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Found by Kepler +3
Total score 46

4 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Super-Earth · +8
  • Tidally locked · +10
  • Multi-planet system · +6
  • Found by Kepler · +3
  • 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. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.
  • Crowded system. One of at least 2 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 14.4 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 July — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

density gcc
5.66
diameter km
16455.498
discovery facility
Kepler
discovery method
Transit
discovery year
2014
dist ly
2717.4176
eccentricity
0
eq temp k
1179
host star teff
6031
inclination
88.44
insolation
599.495
mag
14.357
mass earth
2.21
name
Kepler-173 b
orbital period days
4.2637
radius earth
1.29
semi major au
0.048
sys num planets
2
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About Kepler-173 b

Kepler-173 b is a rare exoplanet. It lies about 2,717.4 light-years from Earth, shines at apparent magnitude 14.36, has an equilibrium temperature near 1,179 K and spans roughly 1.29 Earth radii.

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 14.36, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Kepler-173 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 Kepler-173 b is a rare exoplanet

Kepler-173 b scores 46 points on Spacedle's rarity scale, which places it in the rare tier. Another 4 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Super-Earth, Tidally locked, Multi-planet system, Found by Kepler 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.