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Rare exoplanet 47 EP

TOI-1298 b

RA 241.3229° · Dec 70.1900° · exoplanet

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Score breakdown

· 7 badges
47 pts · Rare
Rare 50 pts → Epic
  • Hot Jupiter +10
  • 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 47

3 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • 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 11.9 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 May — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

density gcc
0.6
diameter km
123200.2767
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2021
dist ly
1040.5551
eccentricity
0
eq temp k
1278
host star teff
5752
inclination
88.96
insolation
732.0077
mag
11.889
mass earth
99
name
TOI-1298 b
orbital period days
4.5371
radius earth
9.6581
semi major au
0.057
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About TOI-1298 b

TOI-1298 b is a rare exoplanet. It lies about 1,040.6 light-years from Earth, shines at apparent magnitude 11.89, has an equilibrium temperature near 1,278 K and spans roughly 9.66 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 11.89, a small backyard telescope will bring it into view.

Like any astronomical target, TOI-1298 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-1298 b is a rare exoplanet

TOI-1298 b scores 47 points on Spacedle's rarity scale, which places it in the rare tier. Another 3 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), 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.