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Rare exoplanet 39 EP

KMT-2021-BLG-0852L b

RA 265.8312° · Dec -33.8918° · exoplanet

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Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Puffy low-density world +12
  • Found by microlensing +12
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 39

11 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Puffy low-density world · +12
  • Found by microlensing · +12

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

  • 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

  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • 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. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 414.4 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 36.8 million years even at the Parker Solar Probe's 192 km/s.

Properties

density gcc
0.299
diameter km
181138.04
discovery facility
KMTNet
discovery method
Microlensing
discovery year
2026
dist ly
23581.0788
mass earth
155.7359
name
KMT-2021-BLG-0852L b
radius earth
14.2
semi major au
7.78
sys num planets
1
sys num stars
1

Nearby objects

About KMT-2021-BLG-0852L b

KMT-2021-BLG-0852L b is a rare exoplanet. It lies about 23,581.1 light-years from Earth, spans roughly 14.2 Earth radii, weighs about 155.74 Earth masses and belongs to a system of 1 known planets.

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

How to see it

Like any astronomical target, KMT-2021-BLG-0852L 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 KMT-2021-BLG-0852L b is a rare exoplanet

KMT-2021-BLG-0852L 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, Distant (over 1,000 light-years), Gas giant, Puffy low-density world and Found by microlensing — 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.