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Rare exoplanet 45 EP

51 Peg b

RA 344.3675° · Dec 20.7691° · exoplanet

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Score breakdown

· 5 badges
45 pts · Rare
Rare 46 pts → Epic
  • Lava world +14
  • Puffy low-density world +12
  • Hot Jupiter +10
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 45

1 more point to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Lava world · +14
  • Puffy low-density world · +12

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. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 886.2 thousand years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 78.7 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 504 years in a starship at a tenth of light speed.
  • Distance. 50.4 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1976.

Saying hello

  • Say hello. A radio message and its reply would take 101 years round-trip.

Standing on it

  • A year here. A full year lasts just 4.2 Earth days.

By the numbers

  • Size. About 14.3× the width of Earth.
  • Volume. About 2924 Earths could fit inside it.
  • Mass. Roughly 146× Earth's mass — about 0.5 Jupiters.
  • Your weight. You'd weigh about 0.7× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. Around 1038°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by Haute-Provence Observatory using the radial velocity method.

Properties

density gcc
0.275
discovery facility
Haute-Provence Observatory
discovery method
Radial Velocity
dist ly
50.4283
eccentricity
0.013
eq temp k
1311.39
insolation
492.82
mass earth
146.2018
name
51 Peg b
orbital period days
4.2308
radius earth
14.3
sys num planets
1
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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.