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Rare exoplanet 39 EP

TOI-1685 b

RA 68.5940° · Dec 43.0370° · exoplanet

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Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Ultra-short period +14
  • Super-Earth +8
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
  • Found by TESS +4
Total score 39

11 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Super-Earth · +8
  • Ultra-short period · +14
  • Found by TESS · +4
  • Orbits a red dwarf · +8

Trivia

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. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.

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 13.4 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 November — that's when to go looking.

Could we get there?

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

Properties

density gcc
5.3
diameter km
18126.5602
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2021
dist ly
122.6846
eccentricity
0
eq temp k
1000
host star teff
3470
inclination
86.62
insolation
213
mag
13.378
mass earth
3.07
name
TOI-1685 b
orbital period days
0.6691
radius earth
1.421
semi major au
0.0116
spect
M3 V
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-1685 b

TOI-1685 b is a rare exoplanet. It lies about 122.7 light-years from Earth, shines at apparent magnitude 13.38, has spectral type M3 V and has an equilibrium temperature near 1,000 K.

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 13.38, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, TOI-1685 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-1685 b is a rare exoplanet

TOI-1685 b scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Super-Earth, Ultra-short period, 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.