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Epic exoplanet 63 EP

HR 8799 e

RA 346.8701° · Dec 21.1340° · exoplanet

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Score breakdown

· 7 badges
63 pts · Epic
Epic 78 pts → Anomaly
  • Directly imaged +16
  • Its star is visible to the naked eye +12
  • Hot Jupiter +10
  • Long-period world +10
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 63

15 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Long-period world · +10
  • Multi-planet system · +6
  • Directly imaged · +16
  • Its star is visible to the naked eye · +12

Trivia

What it actually is

  • What it is made of. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.
  • Crowded system. One of at least 4 planets orbiting its star.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 6 you can see it with your own eyes from a dark site.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around September — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 2.4 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
7.74
diameter km
167291.5676
discovery facility
W. M. Keck Observatory
discovery method
Imaging
discovery year
2010
dist ly
134.5201
eccentricity
0.15
eq temp k
1150
host star teff
7400
inclination
25
insolation
0.0201
mag
5.98
mass earth
3178.3
name
HR 8799 e
orbital period days
20815.6
radius earth
13.1145
semi major au
16.4
spect
A5
sys num planets
4
sys num stars
1

About HR 8799 e

HR 8799 e is an epic exoplanet. It lies about 134.5 light-years from Earth, shines at apparent magnitude 5.98, has spectral type A5 and has an equilibrium temperature near 1,150 K.

Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.

How to see it

At apparent magnitude 5.98, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 8799 e 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 HR 8799 e is an epic exoplanet

HR 8799 e scores 63 points on Spacedle's rarity scale, which places it in the epic tier. Another 15 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Long-period world, Multi-planet system, Directly imaged and Its star is visible to the naked eye — 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.