← Back to dex
Rare exoplanet 39 EP

YZ Cet d

RA 18.1331° · Dec -16.9962° · exoplanet

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 4 badges
39 pts · Rare
Rare 46 pts → Epic
  • Earth-sized +16
  • Nearby (<25 ly) +12
  • Multi-planet system +6
  • Confirmed exoplanet +5
Total score 39

7 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Earth-sized · +16
  • Multi-planet system · +6
  • Nearby (<25 ly) · +12

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 212.8 thousand years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 18.9 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 121 years in a starship at a tenth of light speed.
  • Distance. 12.1 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 2014.

Saying hello

  • Say hello. A radio message and its reply would take 24.2 years round-trip.

Standing on it

  • A year here. A full year lasts just 4.7 Earth days.

By the numbers

  • Size. Almost exactly Earth-sized.
  • Mass. About 1.1× the mass of Earth.
  • Your weight. You'd weigh about 1.0× your Earth weight standing here.
  • Temperature. A scorching 84°C on average.

How we found it

  • Discovery. Found by La Silla Observatory using the radial velocity method.

Cosmic context

  • Crowded system. One of at least 3 planets orbiting its star.

Properties

density gcc
5.48
discovery facility
La Silla Observatory
discovery method
Radial Velocity
dist ly
12.1071
eccentricity
0.07
eq temp k
356.7
insolation
2.7
mass earth
1.09
name
YZ Cet d
orbital period days
4.6563
radius earth
1.03
sys num planets
3

About YZ Cet d

YZ Cet d is a rare exoplanet. It lies about 12.1 light-years from Earth, has an equilibrium temperature near 357 K, spans roughly 1.03 Earth radii and weighs about 1.09 Earth masses.

One of at least 3 planets orbiting its star.

How to see it

Like any astronomical target, YZ Cet d 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 YZ Cet d is a rare exoplanet

YZ Cet d scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 7 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Earth-sized, Multi-planet system and Nearby (<25 ly) — 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.

spacedle A daily roll through the real universe. © 2026 spacedle. Buy me a coffee

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.