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Rare exoplanet 38 EP

Kepler-428 b

RA 290.5817° · Dec 40.5773° · exoplanet

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Score breakdown

· 6 badges
38 pts · Rare
Rare 50 pts → Epic
  • Hot Jupiter +10
  • Tidally locked +10
  • Distant (over 1,000 light-years) +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by Kepler +3
Total score 38

12 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Gas giant · +4
  • Hot Jupiter · +10
  • Tidally locked · +10
  • Found by Kepler · +3

Trivia

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

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 15.4 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • 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 July — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 39.3 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.02
diameter km
154477.582
discovery facility
Kepler
discovery method
Transit
discovery year
2014
dist ly
2238.3564
eccentricity
0.22
eq temp k
1070
host star teff
5150
inclination
89.36
insolation
195.088
mag
15.362
mass earth
403.63
name
Kepler-428 b
orbital period days
3.5256
radius earth
12.11
semi major au
0.0433
spect
K1 V
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About Kepler-428 b

Kepler-428 b is a rare exoplanet. It lies about 2,238.4 light-years from Earth, shines at apparent magnitude 15.36, has spectral type K1 V and has an equilibrium temperature near 1,070 K.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 15.36, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Kepler-428 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 Kepler-428 b is a rare exoplanet

Kepler-428 b scores 38 points on Spacedle's rarity scale, which places it in the rare tier. Another 12 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Gas giant, Hot Jupiter, Tidally locked and Found by Kepler — 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.