← Back to dex
Epic exoplanet 57 EP

TOI-2109 b

RA 253.1863° · Dec 16.5799° · exoplanet

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

Computing the sky for your location…

Score breakdown

· 6 badges
57 pts · Epic
Epic 78 pts → Anomaly
  • Ultra-hot Jupiter +26
  • Ultra-short period +14
  • Confirmed exoplanet +5
  • Gas giant +4
  • Blasted by starlight +4
  • Found by TESS +4
Total score 57

21 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Ultra-hot Jupiter · +26
  • Ultra-short period · +14
  • Blasted by starlight · +4
  • Found by TESS · +4

Trivia

What makes it special

  • Ultra-hot Jupiter. So hot that iron vaporises on the dayside, blows around to the night side and rains back down as molten metal.

Hard to believe

  • A year in a day. Its entire year is over in 16.1 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. 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 10.2 you'll want a small backyard telescope.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around June — that's when to go looking.

Properties

density gcc
2.55
diameter km
192599.4474
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2021
dist ly
854.6624
eq temp k
3646
host star teff
6540
inclination
70.74
insolation
14429
mag
10.217
mass earth
1595.4986
name
TOI-2109 b
orbital period days
0.6725
radius earth
15.0985
semi major au
0.0179
spect
F
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-2109 b

TOI-2109 b is an epic exoplanet. It lies about 854.7 light-years from Earth, shines at apparent magnitude 10.22, has spectral type F and has an equilibrium temperature near 3,646 K.

So hot that iron vaporises on the dayside, blows around to the night side and rains back down as molten metal.

How to see it

At apparent magnitude 10.22, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-2109 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-2109 b is an epic exoplanet

TOI-2109 b scores 57 points on Spacedle's rarity scale, which places it in the epic tier. Another 21 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Ultra-hot Jupiter, Ultra-short period, Blasted by starlight and Found by TESS — 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.