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Trash exoplanet 9 EP

K2-405 b

RA 164.3760° · Dec 12.5356° · exoplanet

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Score breakdown

· 2 badges
9 pts · Trash
Trash 15 pts → Common
  • Confirmed exoplanet +5
  • Neptune-like +4
Total score 9

6 more points to reach Common.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +4

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 12.8 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 March — 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. ≈ 11.3 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.09
diameter km
58283.0778
discovery facility
K2
discovery method
Transit
discovery year
2022
dist ly
643.2905
eq temp k
969
host star teff
4927
inclination
87.6647
insolation
146.577
mag
12.816
mass earth
18.9
name
K2-405 b
orbital period days
3.4355
radius earth
4.569
spect
K0
sys num planets
1
sys num stars
1

About K2-405 b

K2-405 b is a trash exoplanet. It lies about 643.3 light-years from Earth, shines at apparent magnitude 12.82, has spectral type K0 and has an equilibrium temperature near 969 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 12.82, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-405 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 K2-405 b is a trash exoplanet

K2-405 b scores 9 points on Spacedle's rarity scale, which places it in the trash tier. Another 6 points would lift it into a rarer tier.

That score comes from 2 science badges — Confirmed exoplanet and Neptune-like — 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.