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Epic exoplanet 51 EP

HN Peg b

RA 326.1316° · Dec 14.7715° · exoplanet

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Score breakdown

· 5 badges
51 pts · Epic
Epic 68 pts → Anomaly
  • Denser than iron +18
  • Directly imaged +16
  • Frozen world +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 51

17 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Denser than iron · +18
  • Directly imaged · +16

Trivia

What makes it special

  • Frozen world. A deep-frozen world far from its star's warmth.
  • 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. ≈ 1 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 92.3 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 591 years in a starship at a tenth of light speed.
  • Distance. 59.1 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1967.

Saying hello

  • Say hello. A radio message and its reply would take 118 years round-trip.

By the numbers

  • Size. About 11.8× the width of Earth.
  • Volume. About 1633 Earths could fit inside it.
  • Mass. Roughly 6992× Earth's mass — about 22 Jupiters.
  • Your weight. You'd weigh about 50.4× your Earth weight standing here.
  • Density. Denser than solid iron.
  • Temperature. A frigid -262°C — colder than dry ice.

How we found it

  • Discovery. Found by Spitzer Space Telescope using the imaging method.

Properties

density gcc
23.5
discovery facility
Spitzer Space Telescope
discovery method
Imaging
dist ly
59.0949
eq temp k
10.77
insolation
0
mass earth
6991.57
name
HN Peg b
radius earth
11.7768
sys num planets
1

About HN Peg b

HN Peg b is an epic exoplanet. It lies about 59.1 light-years from Earth, has an equilibrium temperature near 11 K, spans roughly 11.78 Earth radii and weighs about 6,991.57 Earth masses.

A deep-frozen world far from its star's warmth.

How to see it

Like any astronomical target, HN Peg 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 HN Peg b is an epic exoplanet

HN Peg b scores 51 points on Spacedle's rarity scale, which places it in the epic tier. Another 17 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Frozen world, Denser than iron and Directly imaged — 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.