← Back to dex
Common exoplanet 21 EP

TOI-1439 b

RA 241.7639° · Dec 67.8776° · exoplanet

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 4 badges
21 pts · Common
Common 22 pts → Uncommon
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Neptune-like +4
  • Found by TESS +4
Total score 21

1 more point to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +4
  • 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 10.6 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 May — 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. ≈ 13.2 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
2.76
diameter km
54121.828
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2024
dist ly
751.1568
eccentricity
0.157
eq temp k
748.4
host star teff
5841
insolation
68.4355
mag
10.55
mass earth
38.5
name
TOI-1439 b
orbital period days
27.644
radius earth
4.2428
semi major au
0.192
sys num planets
1
sys num stars
1

About TOI-1439 b

TOI-1439 b is a common exoplanet. It lies about 751.2 light-years from Earth, shines at apparent magnitude 10.55, has an equilibrium temperature near 748 K and spans roughly 4.24 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 10.55, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-1439 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-1439 b is a common exoplanet

TOI-1439 b scores 21 points on Spacedle's rarity scale, which places it in the common tier. Another 1 point would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Neptune-like, 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.