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Uncommon exoplanet 29 EP

Kepler-172 c

RA 283.3684° · Dec 41.8218° · exoplanet

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Score breakdown

· 5 badges
29 pts · Uncommon
Uncommon 33 pts → Rare
  • Distant (>1000 ly) +10
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
  • Found by Kepler +3
Total score 29

4 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Multi-planet system · +6
  • Found by Kepler · +3
  • Distant (>1000 ly) · +10

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 47.5 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 4.2 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 27 thousand years in a starship at a tenth of light speed.
  • Distance. 2703 light-years from Earth.

Look-back time

  • Look-back time. Its light left before the last ice age ended.

Saying hello

  • Say hello. A radio message and its reply would take 5405 years round-trip.

Standing on it

  • A year here. A full year lasts just 6.4 Earth days.

By the numbers

  • Size. About 2.9× the width of Earth.
  • Volume. About 23.4 Earths could fit inside it.
  • Mass. About 8.6× the mass of Earth.
  • Your weight. You'd weigh about 1.0× your Earth weight standing here.
  • Temperature. Around 697°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by Kepler using the transit method.

Cosmic context

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

Properties

density gcc
2.01
discovery facility
Kepler
discovery method
Transit
dist ly
2702.5025
eccentricity
0
eq temp k
970
insolation
227.225
mass earth
8.55
name
Kepler-172 c
orbital period days
6.389
radius earth
2.86
sys num planets
4

About Kepler-172 c

Kepler-172 c is an uncommon exoplanet. It lies about 2,702.5 light-years from Earth, has an equilibrium temperature near 970 K, spans roughly 2.86 Earth radii and weighs about 8.55 Earth masses.

One of at least 4 planets orbiting its star.

How to see it

Like any astronomical target, Kepler-172 c 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-172 c is an uncommon exoplanet

Kepler-172 c scores 29 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 4 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Sub-Neptune, Multi-planet system, Found by Kepler and Distant (>1000 ly) — 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.