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Rare exoplanet 45 EP

HD 82943 b

RA 143.7114° · Dec -12.1303° · exoplanet

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Score breakdown

· 4 badges
45 pts · Rare
Rare 46 pts → Epic
  • In the habitable zone +30
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 45

1 more point to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Gas giant · +4
  • Multi-planet system · +6

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 1.6 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 140.5 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 900 years in a starship at a tenth of light speed.
  • Distance. 90 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1936.

Saying hello

  • Say hello. A radio message and its reply would take 180 years round-trip.

Standing on it

  • A year here. A full year lasts just 441 Earth days.

By the numbers

  • Size. About 13.5× the width of Earth.
  • Volume. About 2460 Earths could fit inside it.
  • Mass. Roughly 534× Earth's mass — about 1.7 Jupiters.
  • Your weight. You'd weigh about 2.9× your Earth weight standing here.
  • Temperature. A surprisingly temperate 13°C average.

How we found it

  • Discovery. Found by La Silla Observatory using the radial velocity method.

Cosmic context

  • Crowded system. One of at least 2 planets orbiting its star.

Properties

density gcc
1.19
discovery facility
La Silla Observatory
discovery method
Radial Velocity
dist ly
89.9871
eccentricity
0.162
eq temp k
286.13
habitable zone
yes
insolation
1.117
mass earth
534.25
name
HD 82943 b
orbital period days
441.47
radius earth
13.5
sys num planets
2

About HD 82943 b

HD 82943 b is a rare exoplanet. It lies about 90 light-years from Earth, has an equilibrium temperature near 286 K, spans roughly 13.5 Earth radii and weighs about 534.25 Earth masses.

Sits where it's neither too hot nor too cold — liquid water could exist.

How to see it

Like any astronomical target, HD 82943 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 HD 82943 b is a rare exoplanet

HD 82943 b scores 45 points on Spacedle's rarity scale, which places it in the rare tier. Another 1 point would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, In the habitable zone, Gas giant and Multi-planet system — 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.