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Rare exoplanet 33 EP

HD 164604 b

RA 270.7787° · Dec -28.5608° · exoplanet

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Score breakdown

· 4 badges
33 pts · Rare
Rare 46 pts → Epic
  • Denser than iron +18
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 33

13 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Denser than iron · +18
  • Multi-planet system · +6

Trivia

What makes it special

  • Heavyweight. Packed denser than solid iron.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 2.3 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 200.5 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 1284 years in a starship at a tenth of light speed.
  • Distance. 128 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1898.

Saying hello

  • Say hello. A radio message and its reply would take 257 years round-trip.

Standing on it

  • A year here. A full year lasts just 654 Earth days.

By the numbers

  • Size. About 12.3× the width of Earth.
  • Volume. About 1861 Earths could fit inside it.
  • Mass. Roughly 4195× Earth's mass — about 13.2 Jupiters.
  • Your weight. You'd weigh about 27.7× your Earth weight standing here.
  • Density. Denser than solid iron.
  • Temperature. A frigid -103°C — colder than dry ice.

How we found it

  • Discovery. Found by Las Campanas Observatory using the radial velocity method.

Cosmic context

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

Properties

density gcc
12.4
discovery facility
Las Campanas Observatory
discovery method
Radial Velocity
dist ly
128.3858
eccentricity
0.479
eq temp k
170.16
insolation
0.1402
mass earth
4195.335
name
HD 164604 b
orbital period days
653.9
radius earth
12.3
sys num planets
2

About HD 164604 b

HD 164604 b is a rare exoplanet. It lies about 128.4 light-years from Earth, has an equilibrium temperature near 170 K, spans roughly 12.3 Earth radii and weighs about 4,195.33 Earth masses.

Packed denser than solid iron.

How to see it

Like any astronomical target, HD 164604 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 164604 b is a rare exoplanet

HD 164604 b scores 33 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Denser than iron 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.