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Epic exoplanet 63 EP

WASP-172 b

RA 199.4337° · Dec -47.2376° · exoplanet

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Score breakdown

· 7 badges
63 pts · Epic
Epic 68 pts → Anomaly
  • Lava world +14
  • Puffy low-density world +12
  • Hot Jupiter +10
  • Distant (>1000 ly) +10
  • Blasted by starlight +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 63

5 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Lava world · +14
  • Puffy low-density world · +12
  • Blasted by starlight · +8
  • Distant (>1000 ly) · +10

Trivia

What makes it special

  • Lava world. Its surface is likely an ocean of molten rock.
  • Cotton-candy planet. So low-density it would float on water.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 30.8 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 2.7 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 17.6 thousand years in a starship at a tenth of light speed.
  • Distance. 1755 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 271.

Saying hello

  • Say hello. A radio message and its reply would take 3510 years round-trip.

Standing on it

  • A year here. A full year lasts just 5.5 Earth days.

By the numbers

  • Size. About 17.6× the width of Earth.
  • Volume. About 5450 Earths could fit inside it.
  • Mass. Roughly 149× Earth's mass — about 0.5 Jupiters.
  • Your weight. You'd weigh about 0.5× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. Around 1467°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by SuperWASP-South using the transit method.

Properties

density gcc
0.16
discovery facility
SuperWASP-South
discovery method
Transit
dist ly
1755.0781
eccentricity
0
eq temp k
1740
insolation
1506.5
mass earth
149.3801
name
WASP-172 b
orbital period days
5.4774
radius earth
17.5981
sys num planets
1

About WASP-172 b

WASP-172 b is an epic exoplanet. It lies about 1,755.1 light-years from Earth, has an equilibrium temperature near 1,740 K, spans roughly 17.6 Earth radii and weighs about 149.38 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, WASP-172 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 WASP-172 b is an epic exoplanet

WASP-172 b scores 63 points on Spacedle's rarity scale, which places it in the epic tier. Another 5 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Lava world, Puffy low-density world, Blasted by starlight and Distant (>1000 ly) — 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.