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Uncommon exoplanet 28 EP

KMT-2021-BLG-0171L b

RA 269.2417° · Dec -30.0931° · exoplanet

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Score breakdown

· 4 badges
28 pts · Uncommon
Uncommon 34 pts → Rare
  • Found by microlensing +12
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 28

6 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Sub-Neptune · +5
  • Found by microlensing · +12

Trivia

What it actually is

  • What it is made of. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.

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. ≈ 263.6 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 23.4 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 150 thousand years in a starship at a tenth of light speed.

Properties

density gcc
1.64
diameter km
42733.27
discovery facility
KMTNet
discovery method
Microlensing
discovery year
2022
dist ly
15003.176
host star teff
5200
mass earth
11.2
name
KMT-2021-BLG-0171L b
radius earth
3.35
semi major au
3.5
sys num planets
1
sys num stars
1

Nearby objects

About KMT-2021-BLG-0171L b

KMT-2021-BLG-0171L b is an uncommon exoplanet. It lies about 15,003.2 light-years from Earth, spans roughly 3.35 Earth radii, weighs about 11.2 Earth masses and belongs to a system of 1 known planets.

Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.

How to see it

Like any astronomical target, KMT-2021-BLG-0171L 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-0171L b is an uncommon exoplanet

KMT-2021-BLG-0171L b scores 28 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 6 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Sub-Neptune 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.