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Common exoplanet 15 EP

HD 155358 b

RA 257.3931° · Dec 33.3549° · exoplanet

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Score breakdown

· 3 badges
15 pts · Common
Common 24 pts → Uncommon
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 15

9 more points to reach Uncommon.

Badges

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

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 2.5 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 222.1 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 1423 years in a starship at a tenth of light speed.
  • Distance. 142 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1884.

Saying hello

  • Say hello. A radio message and its reply would take 285 years round-trip.

Standing on it

  • A year here. A full year lasts just 194 Earth days.

By the numbers

  • Size. About 13.8× the width of Earth.
  • Volume. About 2628 Earths could fit inside it.
  • Mass. Roughly 315× Earth's mass — about 1 Jupiters.
  • Your weight. You'd weigh about 1.7× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. A scorching 148°C on average.

How we found it

  • Discovery. Found by McDonald Observatory using the radial velocity method.

Cosmic context

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

Properties

density gcc
0.658
discovery facility
McDonald Observatory
discovery method
Radial Velocity
dist ly
142.2683
eccentricity
0.17
eq temp k
421.43
insolation
5.0212
mass earth
314.6517
name
HD 155358 b
orbital period days
194.3
radius earth
13.8
sys num planets
2

About HD 155358 b

HD 155358 b is a common exoplanet. It lies about 142.3 light-years from Earth, has an equilibrium temperature near 421 K, spans roughly 13.8 Earth radii and weighs about 314.65 Earth masses.

One of at least 2 planets orbiting its star.

How to see it

Like any astronomical target, HD 155358 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 155358 b is a common exoplanet

HD 155358 b scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 9 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, 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.