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Epic exoplanet 63 EP

TOI-3688 A b

RA 39.2823° · Dec 54.8512° · exoplanet

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Score breakdown

· 8 badges
63 pts · Epic
Epic 78 pts → Anomaly
  • Lava world +14
  • Two suns in its sky +12
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by TESS +4
Total score 63

15 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Lava world · +14
  • Tidally locked · +10
  • Found by TESS · +4
  • Orbits a Sun-like star · +8
  • Two suns in its sky · +12

Trivia

What makes it special

  • Lava world. Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

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. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

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 12.2 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • 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 October — that's when to go looking.

Properties

density gcc
0.76
diameter km
166862.3276
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2023
dist ly
1292.8106
eccentricity
0
eq temp k
1534
host star teff
5950
inclination
87.9
insolation
924.3
mag
12.241
mass earth
311.4718
multi star system
yes
name
TOI-3688 A b
orbital period days
3.2461
radius earth
13.0809
semi major au
0.0456
sys num planets
1
sys num stars
2
tidally locked
yes
tidally locked inferred
yes

About TOI-3688 A b

TOI-3688 A b is an epic exoplanet. It lies about 1,292.8 light-years from Earth, shines at apparent magnitude 12.24, has an equilibrium temperature near 1,534 K and spans roughly 13.08 Earth radii.

Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

How to see it

At apparent magnitude 12.24, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, TOI-3688 A 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-3688 A b is an epic exoplanet

TOI-3688 A b scores 63 points on Spacedle's rarity scale, which places it in the epic tier. Another 15 points would lift it into a rarer tier.

That score comes from 8 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant, Lava world, Tidally locked, Found by TESS, Orbits a Sun-like star and Two suns in its sky — 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.