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Uncommon exoplanet 22 EP

TOI-4578 b

RA 184.2110° · Dec 75.1402° · exoplanet

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Score breakdown

· 4 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Sub-Neptune +5
  • Found by TESS +4
Total score 22

12 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Found by TESS · +4
  • 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. 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.

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 11.4 you'll want a small backyard telescope.
  • 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 March — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 10.4 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
2.71
diameter km
28953.2908
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2026
dist ly
594.416
eq temp k
842.42
host star teff
5951.32
inclination
88.9414
insolation
119.0248
mag
11.362
mass earth
5.77
name
TOI-4578 b
orbital period days
8.6239
radius earth
2.2697
sys num planets
1
sys num stars
1

About TOI-4578 b

TOI-4578 b is an uncommon exoplanet. It lies about 594.4 light-years from Earth, shines at apparent magnitude 11.36, has an equilibrium temperature near 842 K and spans roughly 2.27 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 11.36, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-4578 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-4578 b is an uncommon exoplanet

TOI-4578 b scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Sub-Neptune, Found by TESS 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.