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Anomaly exoplanet 102 EP

Proxima Cen b

RA 217.3935° · Dec -62.6762° · exoplanet

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Score breakdown

· 7 badges
102 pts · Anomaly
Anomaly 120 pts → Mythic
  • In the habitable zone +30
  • Stellar next door (<10 ly) +25
  • Earth-sized +16
  • Two suns in its sky +12
  • Orbits a red dwarf +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
Total score 102

18 more points to reach Mythic.

Badges

  • Confirmed exoplanet · +5
  • Stellar next door (<10 ly) · +25
  • In the habitable zone · +30
  • Earth-sized · +16
  • Multi-planet system · +6
  • Orbits a red dwarf · +8
  • Two suns in its sky · +12

Trivia

What makes it special

  • Next-door neighbour. One of the closest objects of its kind to the Sun — a first port of call for any interstellar mission we ever build.
  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.
  • Earth-sized. Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

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. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.
  • What the zone means. The habitable zone is only about temperature: it is the band where liquid water could survive on a surface. It is a promising address, not evidence of anything living.
  • Crowded system. One of at least 2 planets orbiting its star.

Sense of scale

  • In perspective. Closer than Proxima Centauri — this is about as near as another star gets.

Properties

density gcc
5.46
diameter km
13011.324
discovery facility
European Southern Observatory
discovery method
Radial Velocity
discovery year
2016
dist ly
4.2439
eccentricity
0
eq temp k
218
habitable zone
yes
host star teff
2900
insolation
0.641
mag
11.01
mass earth
1.055
multi star system
yes
name
Proxima Cen b
orbital period days
11.1846
radius earth
1.02
semi major au
0.0485
spect
M5.5 V
sys num planets
2
sys num stars
3

About Proxima Cen b

Proxima Cen b is an anomaly exoplanet. It lies about 4.2 light-years from Earth, shines at apparent magnitude 11.01, has spectral type M5.5 V and has an equilibrium temperature near 218 K.

One of the closest objects of its kind to the Sun — a first port of call for any interstellar mission we ever build.

How to see it

At apparent magnitude 11.01, a small backyard telescope will bring it into view.

Like any astronomical target, Proxima Cen 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 Proxima Cen b is an anomaly exoplanet

Proxima Cen b scores 102 points on Spacedle's rarity scale, which places it in the anomaly tier. Another 18 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Stellar next door (<10 ly), In the habitable zone, Earth-sized, Multi-planet system, Orbits a red dwarf 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.