← Back to dex
Rare exoplanet 35 EP

HD 11964 c

RA 29.2884° · Dec -10.2435° · exoplanet

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

Computing the sky for your location…

Score breakdown

· 5 badges
35 pts · Rare
Rare 50 pts → Epic
  • Two suns in its sky +12
  • Orbits a Sun-like star +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Neptune-like +4
Total score 35

15 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +4
  • Multi-planet system · +6
  • Orbits a Sun-like star · +8
  • Two suns in its sky · +12

Trivia

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

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.
  • Crowded system. One of at least 2 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 6.4 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around October — that's when to go looking.

Properties

density gcc
0.882
diameter km
68628.356
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
discovery year
2008
dist ly
109.3826
eccentricity
0.3
eq temp k
757.54
host star teff
5303
insolation
54.875
mag
6.4153
mass earth
25
multi star system
yes
name
HD 11964 c
orbital period days
37.91
radius earth
5.38
semi major au
0.229
spect
G9 V CN+1
sys num planets
2
sys num stars
2

Nearby objects

About HD 11964 c

HD 11964 c is a rare exoplanet. It lies about 109.4 light-years from Earth, shines at apparent magnitude 6.42, has spectral type G9 V CN+1 and has an equilibrium temperature near 758 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 6.42, it is an easy target for binoculars.

Like any astronomical target, HD 11964 c 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 HD 11964 c is a rare exoplanet

HD 11964 c scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Neptune-like, Multi-planet system, Orbits a Sun-like star and Two suns in its sky — 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.