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Uncommon exoplanet 22 EP

TOI-1859 b

RA 279.8318° · Dec 69.5229° · exoplanet

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Score breakdown

· 4 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Eccentric orbit +9
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by TESS +4
Total score 22

12 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Eccentric orbit · +9
  • Found by TESS · +4

Trivia

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 10.3 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 June — that's when to go looking.

Could we get there?

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

Properties

density gcc
0.406
diameter km
124396.0797
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2023
dist ly
731.8451
eccentricity
0.57
eq temp k
615
host star teff
6341
inclination
88.64
insolation
23.786
mag
10.33
mass earth
68.6
name
TOI-1859 b
orbital period days
63.4835
radius earth
9.7518
semi major au
0.337
sys num planets
1
sys num stars
1

About TOI-1859 b

TOI-1859 b is an uncommon exoplanet. It lies about 731.8 light-years from Earth, shines at apparent magnitude 10.33, has an equilibrium temperature near 615 K and spans roughly 9.75 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 10.33, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-1859 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-1859 b is an uncommon exoplanet

TOI-1859 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, Gas giant, Eccentric orbit 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.