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Rare exoplanet 47 EP

GJ 1252 b

RA 306.9286° · Dec -56.4623° · exoplanet

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Score breakdown

· 5 badges
47 pts · Rare
Rare 50 pts → Epic
  • Earth-sized +16
  • Ultra-short period +14
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
  • Found by TESS +4
Total score 47

3 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Earth-sized · +16
  • Ultra-short period · +14
  • Found by TESS · +4
  • Orbits a red dwarf · +8

Trivia

What makes it special

  • Earth-sized. Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

Hard to believe

  • A year in a day. Its entire year is over in 12.4 hours. Birthdays here would come round faster than meals.

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.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 12.7 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around July — that's when to go looking.

Properties

density gcc
4.2
diameter km
15218.1466
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2020
dist ly
66.4478
eccentricity
0
eq temp k
1090
host star teff
3458
inclination
85
insolation
233
mag
12.68
mass earth
1.32
name
GJ 1252 b
orbital period days
0.5182
radius earth
1.193
semi major au
0.0092
spect
M3
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

Nearby objects

About GJ 1252 b

GJ 1252 b is a rare exoplanet. It lies about 66.4 light-years from Earth, shines at apparent magnitude 12.68, has spectral type M3 and has an equilibrium temperature near 1,090 K.

Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

How to see it

At apparent magnitude 12.68, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, GJ 1252 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 GJ 1252 b is a rare exoplanet

GJ 1252 b scores 47 points on Spacedle's rarity scale, which places it in the rare tier. Another 3 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Earth-sized, Ultra-short period, Found by TESS and Orbits a red dwarf — 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.