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Rare exoplanet 41 EP

TOI-905 b

RA 227.6587° · Dec -71.3616° · exoplanet

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Score breakdown

· 6 badges
41 pts · Rare
Rare 50 pts → Epic
  • Hot Jupiter +10
  • Tidally locked +10
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by TESS +4
Total score 41

9 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Tidally locked · +10
  • Found by TESS · +4
  • Orbits a Sun-like star · +8

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 11.1 you'll want a small backyard telescope.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • 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.

Properties

density gcc
0.515
diameter km
167434.5518
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2020
dist ly
517.4432
eccentricity
0.024
eq temp k
1192
host star teff
5570
inclination
85.68
insolation
337
mag
11.08
mass earth
211.9926
name
TOI-905 b
orbital period days
3.7395
radius earth
13.1257
semi major au
0.0467
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-905 b

TOI-905 b is a rare exoplanet. It lies about 517.4 light-years from Earth, shines at apparent magnitude 11.08, has an equilibrium temperature near 1,192 K and spans roughly 13.13 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 11.08, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-905 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-905 b is a rare exoplanet

TOI-905 b scores 41 points on Spacedle's rarity scale, which places it in the rare tier. Another 9 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Tidally locked, 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.