← Back to dex
Rare exoplanet 40 EP

HD 103949 b

RA 179.5480° · Dec -23.9241° · exoplanet

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

Computing the sky for your location…

Score breakdown

· 3 badges
40 pts · Rare
Rare 50 pts → Epic
  • In the habitable zone +30
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 40

10 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Sub-Neptune · +5

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

What it actually is

  • What it is made of. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.
  • What the zone means. The habitable zone is only about temperature: it is the band where liquid water could survive on a surface. It is a promising address, not evidence of anything living.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 8.7 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 March — that's when to go looking.

Could we get there?

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

Properties

density gcc
1.64
diameter km
42733.27
discovery facility
Las Campanas Observatory
discovery method
Radial Velocity
discovery year
2019
dist ly
86.4304
eccentricity
0.19
eq temp k
302.65
habitable zone
yes
host star teff
4792
insolation
1.3983
mag
8.7
mass earth
11.2
name
HD 103949 b
orbital period days
120.878
radius earth
3.35
semi major au
0.439
spect
K3 V
sys num planets
1
sys num stars
1

About HD 103949 b

HD 103949 b is a rare exoplanet. It lies about 86.4 light-years from Earth, shines at apparent magnitude 8.7, has spectral type K3 V and has an equilibrium temperature near 303 K.

Sits where it's neither too hot nor too cold — liquid water could exist on a surface here.

How to see it

At apparent magnitude 8.7, it is an easy target for binoculars.

Like any astronomical target, HD 103949 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 HD 103949 b is a rare exoplanet

HD 103949 b scores 40 points on Spacedle's rarity scale, which places it in the rare tier. Another 10 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, In the habitable zone and Sub-Neptune — 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.