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Epic exoplanet 52 EP

TOI-2257 b

RA 194.7396° · Dec 77.6617° · exoplanet

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Score breakdown

· 5 badges
52 pts · Epic
Epic 78 pts → Anomaly
  • In the habitable zone +30
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
  • Sub-Neptune +5
  • Found by TESS +4
Total score 52

26 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Sub-Neptune · +5
  • Found by TESS · +4
  • Orbits a red dwarf · +8

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

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. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.
  • 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.

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 15.2 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around April — that's when to go looking.

Properties

density gcc
2.84
diameter km
27987.1028
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2021
dist ly
188.4891
eccentricity
0.496
eq temp k
256
habitable zone
yes
host star teff
3430
inclination
89.786
insolation
0.6703
mag
15.211
mass earth
5.45
name
TOI-2257 b
orbital period days
35.1893
radius earth
2.194
semi major au
0.145
spect
M3
sys num planets
1
sys num stars
1

About TOI-2257 b

TOI-2257 b is an epic exoplanet. It lies about 188.5 light-years from Earth, shines at apparent magnitude 15.21, has spectral type M3 and has an equilibrium temperature near 256 K.

Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

How to see it

At apparent magnitude 15.21, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, TOI-2257 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 TOI-2257 b is an epic exoplanet

TOI-2257 b scores 52 points on Spacedle's rarity scale, which places it in the epic tier. Another 26 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, In the habitable zone, Sub-Neptune, 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.