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Uncommon exoplanet 24 EP

HD 203387 b

RA 320.5618° · Dec -16.8345° · exoplanet

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Score breakdown

· 4 badges
24 pts · Uncommon
Uncommon 33 pts → Rare
  • Eccentric orbit +9
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 24

9 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Eccentric orbit · +9
  • Multi-planet system · +6

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 3.5 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 314.5 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 2014 years in a starship at a tenth of light speed.
  • Distance. 201 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1825.

Saying hello

  • Say hello. A radio message and its reply would take 403 years round-trip.

Standing on it

  • A year here. A full year lasts just 513 Earth days.

By the numbers

  • Size. About 13.1× the width of Earth.
  • Volume. About 2248 Earths could fit inside it.
  • Mass. Roughly 1106× Earth's mass — about 3.5 Jupiters.
  • Your weight. You'd weigh about 6.4× your Earth weight standing here.
  • Temperature. A scorching 337°C on average.

How we found it

  • Discovery. Found by Multiple Observatories using the radial velocity method.

Cosmic context

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

Properties

density gcc
2.7
discovery facility
Multiple Observatories
discovery method
Radial Velocity
dist ly
201.3938
eccentricity
0.732
eq temp k
610
insolation
23.0974
mass earth
1106.0429
name
HD 203387 b
orbital period days
512.5352
radius earth
13.1
sys num planets
2

About HD 203387 b

HD 203387 b is an uncommon exoplanet. It lies about 201.4 light-years from Earth, has an equilibrium temperature near 610 K, spans roughly 13.1 Earth radii and weighs about 1,106.04 Earth masses.

One of at least 2 planets orbiting its star.

How to see it

Like any astronomical target, HD 203387 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 203387 b is an uncommon exoplanet

HD 203387 b scores 24 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Eccentric orbit 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.